How we check the calculators
Current version: v1.8 · last review: 30 October 2026. Every result below was produced by this version.
Formulas that look right can still be wrong, so every calculator on this site was checked by a separate review. To be clear about who did it: the review was carried out by AI review agents that had not written the code and were instructed to be sceptical, not by a licensed professional engineer, and no calculator has yet been reviewed or signed off by one. For each tool the reviewer read the formulas and the code, compared them with textbooks, standards and manufacturer data (Shigley's Mechanical Engineering Design, Machinery's Handbook, ISO, DIN, AGMA and EN standards, and catalogues from SKF, Gates, Tsubaki, KHK, Bosch Rexroth and others), recomputed the default case and the worked example with separate code, and where possible ran a published worked example through the calculator.
In total 352 results were compared. Where the review found a mistake, it was corrected and is listed under the tool. The tables show the value the reference gives, the value the current calculator gives, the difference, and a verdict: match, method difference (the calculator deliberately uses a documented simplification, explained in the note) or error.
These are design calculators, not certification. For safety-critical parts, check the final design against the full standard and the supplier's data. If you find a number that looks wrong – and especially if you are a practising engineer willing to review a calculator – please tell us; reviews by named engineers will be listed here.
Re-run the tests yourself
Every check below is also an automatic test: the inputs, the value the reference gives and the allowed tolerance. The button loads each live calculator in your browser, enters the inputs and compares the result. Nothing is sent anywhere. The test definitions are in tests.json.
| Calculator | Test | Expected | Got | Tol. |
|---|
Pulley & Belt Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default belt length 90/280 mm, C=450 (mm) | Shigley's MED 10th ed., eq. 17-1 (open-belt length L=√(4C²−(D−d)²)+½(DθD+dθd), θd=π−2asin((D−d)/2C)) | 1501.3257 | 1501.3 | -0.0 | match | |
| Center distance for SPZ 1500 datum belt (mm) | Shigley's MED 10th ed., eq. 17-1 (open-belt length L=√(4C²−(D−d)²)+½(DθD+dθd), θd=π−2asin((D−d)/2C)) solved for C; ISO 4184 R40 length 1500 | 449.3218 | 449.3 | -0.0 | match | |
| Driven speed (rpm) | n2=n1·d1/d2 (kinematics) | 466.0714 | 466 | -0.02 | match | |
| Belt speed (m/s) | v=π·d·n/60000 | 6.833 | 6.83 | -0.04 | match | |
| Effective pull Fe (N) | Fe=P/v | 321.9686 | 322 | 0.01 | match | |
| Wrap on small pulley (deg) | Shigley's MED 10th ed., eq. 17-1 (open-belt length L=√(4C²−(D−d)²)+½(DθD+dθd), θd=π−2asin((D−d)/2C)) θd | 155.6251 | 155.6 | -0.02 | match | |
| Shigley Ex. 17-1 (6 in / 18 in, C = 96 in): belt length (in) | Shigley MED 10th ed. Ex. 17-1 (L = 230.1 in) | 230.0742 | 230.07 | -0.0 | match | |
| Shigley Ex. 17-1: belt speed at 1750 rpm (ft/min) | Shigley MED 10th ed. Ex. 17-1 (V = 2749 ft/min) | 2748.8936 | 2749 | 0.0 | match | |
| Shigley Ex. 17-1: small-pulley wrap (deg) | Shigley MED 10th ed. Ex. 17-1 (φd = 3.0165 rad = 172.83°) | 172.8327 | 172.8 | -0.02 | match | |
| HTD 5M 20T/60T at C=300 mm: pitch length (mm) | d=z·p/π (Gates HTD), open-belt length eq. 17-1 | 803.3806 | 803.4 | 0.0 | match | |
| HTD 5M 20T/60T: teeth in mesh on small pulley | z·θ/360 (Gates design manual, ≥6 teeth) | 9.3233 | 9.3 | -0.25 | match |
Chain & Sprocket Corrected
Corrected after the review:
- Wrap angle and center distance in pitches now use the center distance the even link count actually gives.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Exact link count 17T/42T 08B at C=450 mm | Shigley's MED 10th ed. eq. 17-34/17-35 (chain length / center distance) | 100.8129 | 100.81 | -0.0 | match | |
| Center distance for 102 links (mm) | Shigley's MED 10th ed. eq. 17-34/17-35 (chain length / center distance) | 457.5849 | 457.6 | 0.0 | match | |
| Pitch diameter z17 (mm) | Dp=p/sin(180°/z) (Machinery's Handbook / Shigley eq. 17-31) | 69.1158 | 69.12 | 0.01 | match | |
| Outside diameter z17 (mm) | Do=p(0.6+cot(180°/z)) (Machinery's Handbook, ANSI sprocket OD) | 75.559 | 75.56 | 0.0 | match | |
| Chain speed (m/s) | v=z1·p·n1/60000 (Shigley eq. 17-32) | 2.5188 | 2.52 | 0.05 | match | |
| Chain pull (N) | F=P/v | 595.5138 | 596 | 0.08 | match | |
| Static SF vs ISO 606 08B-1 17.8 kN | ISO 606:2015 min. tensile 08B-1 = 17.8 kN | 29.8902 | 29.9 | 0.03 | match | |
| Wrap on small sprocket at installed C (deg) | 180°−2·asin((D2−D1)/2C) with pitch diameters | 167.3492 | 167.3 | -0.03 | match | |
| Chordal speed variation z17 (%) | Shigley eq. 17-37 / 1−cos(180°/z) | 1.7027 | 1.7 | -0.16 | match | |
| Tsubaki selection example 17T/51T, C = 19 pitches: links (rounded up even) | U.S. Tsubaki "Chain Drive Selection" Step 5 (73.5 → 74 links) | 74 | 74 | 0.0 | match | |
| ANSI #40 static SF (break 13.9 kN = 12 500·p² lbf) | ASME B29.1 min. ultimate tensile 3125 lbf (#40) | 23.3412 | 23.3 | -0.18 | match |
Timing Belt Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Two-pulley belt length (z20/z40 HTD 5M, C 300 mm) | Exact open-belt length formula | 750.84 | 750.8 | -0.01 | match | Checked by the developer; independent review pending (new calculator). |
| Small-pulley wrap, two pulleys | 180° − 2·asin((R − r)/C) | 173.9 | 174 | 0.06 | match | Checked by the developer; independent review pending. |
| Sum of wraps around a closed loop (DOHC preset, back-side tensioner subtracts) | Σθ(inside) − Σθ(back) = 360° | 360 | 359.9 | -0.03 | match | Checked by the developer; independent review pending. |
CVT Variator Corrected
Corrected after the review:
- Belts longer than the primary limit are accepted; the full secondary then limits the low ratio.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Low ratio 50 cc preset (41 mm primary) | Open-belt length L=2C+π(d1+d2)/2+(d2−d1)²/4C solved for d2 (Shigley eq. 17-1 approx.) | 2.6537 | 2.65 | -0.14 | match | |
| Overdrive ratio (92 mm primary) | Open-belt length L=2C+π(d1+d2)/2+(d2−d1)²/4C solved for d2 (Shigley eq. 17-1 approx.) | 0.6536 | 0.65 | -0.55 | match | |
| Ratio spread | Open-belt length L=2C+π(d1+d2)/2+(d2−d1)²/4C solved for d2 (Shigley eq. 17-1 approx.) | 4.0603 | 4.06 | -0.01 | match | |
| Top speed in overdrive at 7500 rpm (km/h) | v=n/(i·i_f)·π·D_tire | 68.8972 | 68.9 | 0.0 | match | |
| Speed in lowest ratio (km/h) | v=n/(i·i_f)·π·D_tire | 16.9685 | 17 | 0.19 | match | |
| Primary sheave travel (mm) | x=Δd·tan(α/2) for one moving half (Δr=x·tan(α/2)... geometry of a V-groove) | 12.7157 | 12.7 | -0.12 | match | |
| Secondary sheave travel (mm) | x=Δd·tan(α/2) | 12.1357 | 12.1 | -0.29 | match | |
| Wrap small pulley, low ratio (deg) | 180°−2asin(|D−d|/2C) | 164.0927 | 164 | -0.06 | match | |
| Belt speed in overdrive (m/s) | v=π·d1·n/60000 | 36.1283 | 36.1 | -0.08 | match | |
| 740 mm belt (secondary-limited): low ratio | same equation solved for d1 with d2 = 112 mm | 2.5359 | 2.54 | 0.16 | match | |
| 740 mm belt: overdrive ratio | same equation | 0.7254 | 0.73 | 0.63 | match |
Spur & Helical Gears Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Center distance m2 18/45 (mm) | ISO 21771: a=m(z1+z2)/2 | 63.0 | 63 | 0.0 | match | |
| Contact ratio m2 18/45 | ISO 21771 transverse contact ratio εα | 1.6328 | 1.63 | -0.17 | match | |
| Output torque (N·m) | T2=T1·i·η, η=0.98 per stated note | 24.5 | 24.5 | 0.0 | match | |
| Tangential tooth force (N) | Ft=2000T/d1 | 555.5556 | 556 | 0.08 | match | |
| KHK profile-shift example: working center distance (mm) | KHK Gear Technical Reference, profile-shifted spur gear example (m3, z12/24, x 0.6/0.36: αw 26.0886°, a 56.4999, da 44.840/79.400, df 32.100/66.660) | 56.4999 | 56.5 | 0.0 | match | |
| KHK example: working pressure angle (deg) | KHK Gear Technical Reference, profile-shifted spur gear example (m3, z12/24, x 0.6/0.36: αw 26.0886°, a 56.4999, da 44.840/79.400, df 32.100/66.660) | 26.0886 | 26.09 | 0.01 | match | |
| KHK example: tip diameter da1 (mm) | KHK Gear Technical Reference, profile-shifted spur gear example (m3, z12/24, x 0.6/0.36: αw 26.0886°, a 56.4999, da 44.840/79.400, df 32.100/66.660) | 44.84 | 44.84 | 0.0 | match | |
| KHK example: root diameter df2 (mm) | KHK Gear Technical Reference, profile-shifted spur gear example (m3, z12/24, x 0.6/0.36: αw 26.0886°, a 56.4999, da 44.840/79.400, df 32.100/66.660) | 66.66 | 66.66 | 0.0 | match | |
| KHK helical example: center distance (mm) | KHK Gear Technical Reference, normal-system helical example (mn3, z12/60, β30°, xn 0.09809/0 → a = 125 mm) | 125.0 | 125 | -0.0 | match | |
| KHK helical example: tip diameter da1 (mm) | KHK Gear Technical Reference, normal-system helical example (mn3, z12/60, β30°, xn 0.09809/0 → a = 125 mm) (da1 = d1 + 2(1+y−xn2)mn) | 48.1539 | 48.154 | 0.0 | match | |
| FAQ 12/30 m2 x1=0.3: working center distance (mm) | involute function inv αw = 2tanα·Σx/Σz + inv α (ISO 21771) | 42.5719 | 42.57 | -0.0 | match |
Gear Tooth Strength Corrected
Corrected after the review:
- Overload factor labels aligned with AGMA (1.25 moderate, 1.75 heavy shock).
- Size and reliability factor assumptions (Ks = KR = 1) now stated.
- Added helical gears (normal module, helix angle, load sharing ratio, axial force).
- Radial force Fr = Ft·tanαn/cosβ now shown.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default pinion bending σF (MPa) | Shigley's MED 10th ed. ch. 14 (Lewis Y Table 14-2, AGMA Kv eq. 14-27, I eq. 14-23, YN/ZN Figs 14-14/14-15, grade 1 St/Sc Figs 14-2/14-5) Lewis σ=Ft·Ka·Kv·Km/(b·m·Y) | 126.1978 | 126 | -0.16 | match | |
| Default contact stress σH (MPa) | Shigley's MED 10th ed. ch. 14 (Lewis Y Table 14-2, AGMA Kv eq. 14-27, I eq. 14-23, YN/ZN Figs 14-14/14-15, grade 1 St/Sc Figs 14-2/14-5) eq. 14-16 with ZE=191 √MPa | 784.2198 | 784 | -0.03 | match | |
| Default pinion bending SF (300 HB, 1.74e9 cycles) | Shigley's MED 10th ed. ch. 14 (Lewis Y Table 14-2, AGMA Kv eq. 14-27, I eq. 14-23, YN/ZN Figs 14-14/14-15, grade 1 St/Sc Figs 14-2/14-5) SF=St·YN/σ | 1.8258 | 1.83 | 0.23 | match | |
| Default pinion SH | Shigley's MED 10th ed. ch. 14 (Lewis Y Table 14-2, AGMA Kv eq. 14-27, I eq. 14-23, YN/ZN Figs 14-14/14-15, grade 1 St/Sc Figs 14-2/14-5) SH=Sc·ZN/σH | 0.9807 | 0.98 | -0.08 | match | |
| Shigley Ex. 14-4 spur: transmitted load Wt (lbf) | Shigley MED 10th ed. Ex. 14-4 (17/52T, Pd 10, F 1.5 in, 1800 rpm, 4 hp, Qv 6, gear 200 HB, 1e8 pinion cycles, R 0.90): Wt 164.8 lbf, Kv 1.377, Ks 1.052 (gear), Km 1.22, JG 0.40, KR 0.85, σG 4854 psi, SF,G 6.82, σc,G 70 660 psi, SH,G 1.52 | 164.8 | 165 | 0.12 | match | |
| Shigley Ex. 14-4 contact-stress formula with page factors (Kv 1.304, Km 1.30, Ks=1) (ksi) | Shigley eq. 14-16 σc=Cp√(Wt·Ko·Kv·Ks·Km·Cf/(dP·F·I)), Cp 2300, I 0.1211 | 69.1839 | 69.2 | 0.02 | match | |
| Shigley Ex. 14-4 gear contact stress vs published 70.66 ksi | Shigley MED 10th ed. Ex. 14-4 (17/52T, Pd 10, F 1.5 in, 1800 rpm, 4 hp, Qv 6, gear 200 HB, 1e8 pinion cycles, R 0.90): Wt 164.8 lbf, Kv 1.377, Ks 1.052 (gear), Km 1.22, JG 0.40, KR 0.85, σG 4854 psi, SF,G 6.82, σc,G 70 660 psi, SH,G 1.52 | 70.66 | 69.2 | -2.07 | method difference | Page −2.1 %: Ks=1 instead of 1.052 (−2.5 %), Km 1.30 instead of 1.22 (+3.2 %), nearest Qv tile is 7 (Kv 1.304 vs 1.377, −2.7 %); √ of these = 0.9796 reproduces the page exactly. |
| Shigley Ex. 14-4 gear bending SF vs published 6.82 | Shigley MED 10th ed. Ex. 14-4 (17/52T, Pd 10, F 1.5 in, 1800 rpm, 4 hp, Qv 6, gear 200 HB, 1e8 pinion cycles, R 0.90): Wt 164.8 lbf, Kv 1.377, Ks 1.052 (gear), Km 1.22, JG 0.40, KR 0.85, σG 4854 psi, SF,G 6.82, σc,G 70 660 psi, SH,G 1.52 | 6.82 | 6.22 | -8.8 | method difference | Page 8.8 % lower. Ks/KR simplification alone: KR=1 (99 %) vs 0.85 (R 0.90) lowers SF 15.0 %, Ks=1 vs 1.052 raises it 5.2 % → net ×0.894 (−10.6 %); remaining: Km 1.30 vs 1.22 (−6.2 %), Kv Qv7 vs Qv6 (+5.6 %), Lewis Y 0.412 vs J 0.40 (+3.0 %). Product 0.9115 × 6.82 = 6.22 = page. |
| Shigley Ex. 14-4 gear wear SH vs published 1.52 | Shigley MED 10th ed. Ex. 14-4 (17/52T, Pd 10, F 1.5 in, 1800 rpm, 4 hp, Qv 6, gear 200 HB, 1e8 pinion cycles, R 0.90): Wt 164.8 lbf, Kv 1.377, Ks 1.052 (gear), Km 1.22, JG 0.40, KR 0.85, σG 4854 psi, SF,G 6.82, σc,G 70 660 psi, SH,G 1.52 | 1.52 | 1.31 | -13.82 | method difference | Page 13.8 % lower. Ks/KR simplification: KR=1 vs 0.85 (−15.0 %) and Ks=1 vs 1.052 (+2.6 % on SH) → net ×0.872 (−12.8 %); also CH 1.005 omitted (−0.5 %), Km/Kv differences (+2.1 %). Product 0.8634 × 1.52 = 1.312 = page. |
| Shigley Ex. 14-5 helical: load-sharing ratio mN | Shigley MED 10th ed. Ex. 14-5 (Ex. 14-4 as helical, ψ 30°, Pn 10): Pt 8.660, dP 1.963 in, V 925 ft/min, Wt 142.7 lbf, Kv 1.404, Km 1.208, mN 0.6895, I 0.195, JG 0.529, σG 2779 psi, SF,G 11.9, σc,G 48 440 psi, SH,G 2.22 | 0.6895 | 0.69 | 0.07 | match | |
| Shigley Ex. 14-5 helical gear wear SH vs published 2.22 | Shigley MED 10th ed. Ex. 14-5 (Ex. 14-4 as helical, ψ 30°, Pn 10): Pt 8.660, dP 1.963 in, V 925 ft/min, Wt 142.7 lbf, Kv 1.404, Km 1.208, mN 0.6895, I 0.195, JG 0.529, σG 2779 psi, SF,G 11.9, σc,G 48 440 psi, SH,G 2.22 | 2.22 | 1.91 | -13.96 | method difference | Page 14 % lower: Ks/KR simplification (KR 1 vs 0.85, Ks 1 vs 1.052) = ×0.872 (−12.8 %), CH omitted −0.5 %, Km/Kv −1.7 %; product 0.8604 × 2.22 = 1.91. |
| Shigley Ex. 14-5 helical gear bending SF vs published 11.9 | Shigley MED 10th ed. Ex. 14-5 (Ex. 14-4 as helical, ψ 30°, Pn 10): Pt 8.660, dP 1.963 in, V 925 ft/min, Wt 142.7 lbf, Kv 1.404, Km 1.208, mN 0.6895, I 0.195, JG 0.529, σG 2779 psi, SF,G 11.9, σc,G 48 440 psi, SH,G 2.22 | 11.9 | 7.51 | -36.89 | method difference | Page 37 % lower (conservative): page applies Lewis σ=Ft·K/(b·mn·Y(zv)) with the normal module and no helical load-sharing, while AGMA uses Pt and J (0.529, incl. J′ multiplier); Ks/KR part of the gap is ×0.894 (−10.6 %), Lewis/normal-pitch part ×0.70; product 0.630 × 11.9 = 7.50. |
| Shigley Ex. 14-4, AGMA rating option (Ks, KR 0.85): gear contact SH | Shigley MED 10th ed., Example 14-4 | 1.52 | 1.51 | -0.66 | match | With the AGMA rating option the earlier −13.8 % method difference disappears; the remaining −0.7 % comes from Qv 7 vs 6 and Km 1.30 vs 1.22. |
| Shigley Ex. 14-4, AGMA rating option: gear bending SF | Shigley MED 10th ed., Example 14-4 | 6.82 | 6.96 | 2.05 | method difference | Lewis Y (0.412) instead of AGMA geometry factor J (0.40) and simplified Km; within 2 %. |
Worm Gear Corrected
Corrected after the review:
- Running friction now follows the AGMA equation; static friction for the self-locking check raised to 0.15 (AGMA).
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Center distance (mm) | DIN 3975 a=(d1+d2)/2=(q+z2)m/2 | 62.5 | 62.5 | 0.0 | match | |
| Lead angle (deg) | DIN 3975 tanγ=z1/q | 11.3099 | 11.31 | 0.0 | match | |
| Sliding speed (m/s) | vs=π·d1·n1/(60000·cosγ) | 1.9356 | 1.94 | 0.23 | match | |
| Efficiency with AGMA friction (%) | DIN 3975 geometry; AGMA 6034 / Shigley eq. 15-38 friction; η=tanγ/tan(γ+ρ′) ≡ Shigley eq. 13-46 | 84.5084 | 84.5 | -0.01 | match | |
| Output torque (N·m) | T2=9549P/n1·i·η | 166.9595 | 167 | 0.02 | match | |
| Heat to remove (W) | P(1−η) | 232.3733 | 232 | -0.16 | match | |
| Shigley worm example: efficiency (%) | Shigley MED ch. 15 worm example (1 start, 75T, px 0.375 in, dW 2 in, 1750 rpm): λ 3.42°, Vs 917.9 ft/min, f 0.0216, e 0.721, C 5.476 in (https://gennonotes.github.io/EMEC-4438/EngDes2-W13.pdf) | 72.06 | 72.1 | 0.06 | match | |
| Shigley worm example: AGMA friction f | Shigley MED ch. 15 worm example (1 start, 75T, px 0.375 in, dW 2 in, 1750 rpm): λ 3.42°, Vs 917.9 ft/min, f 0.0216, e 0.721, C 5.476 in (https://gennonotes.github.io/EMEC-4438/EngDes2-W13.pdf) | 0.0216 | 0.022 | 1.85 | match | Display rounded to 3 decimals (0.022 vs 0.0216); within rounding. |
| Shigley worm example: sliding speed (m/s; 917.9 ft/min) | Shigley MED ch. 15 worm example (1 start, 75T, px 0.375 in, dW 2 in, 1750 rpm): λ 3.42°, Vs 917.9 ft/min, f 0.0216, e 0.721, C 5.476 in (https://gennonotes.github.io/EMEC-4438/EngDes2-W13.pdf) | 4.6629 | 4.66 | -0.06 | match | |
| Shigley worm example: center distance (in) | Shigley MED ch. 15 worm example (1 start, 75T, px 0.375 in, dW 2 in, 1750 rpm): λ 3.42°, Vs 917.9 ft/min, f 0.0216, e 0.721, C 5.476 in (https://gennonotes.github.io/EMEC-4438/EngDes2-W13.pdf) | 5.476 | 5.476 | 0.0 | match | |
| Static friction angle for self-locking (deg), 1-start q=10 | AGMA static f=0.15 → ρ′=atan(0.15/cos20°) | 9.0694 | 9.07 | 0.01 | match |
Planetary Gear Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Ratio, ring held (21/27/75) | Willis equation (KHK Gear Technical Reference, planetary gear systems): i=1+Zr/Zs | 4.5714 | 4.571 | -0.01 | match | |
| Carrier speed (rpm) | Willis equation (KHK Gear Technical Reference, planetary gear systems) | 656.25 | 656 | -0.04 | match | |
| Output torque (N·m) | T·i·0.97 (stated η) | 22.1714 | 22.2 | 0.13 | match | |
| Ring reaction (N·m) | torque balance Tout−Tin | 17.1714 | 17.2 | 0.17 | match | |
| Planet speed relative to carrier (rpm) | Willis equation (KHK Gear Technical Reference, planetary gear systems): (ns−nc)Zs/Zp | 1822.9167 | 1823 | 0.0 | match | |
| Sun-to-planet center distance (mm) | a=m(Zs+Zp)/2 | 36.0 | 36 | 0.0 | match | |
| KHK example Zs16/Zp16/Zr48, ring fixed, N=4: ratio | KHK Gear Technical Reference planetary example (i = 1+Zr/Zs = 4) | 4 | 4 | 0.0 | match | |
| Sun held, ring → carrier ratio | Willis equation (KHK Gear Technical Reference, planetary gear systems): 1+Zs/Zr | 1.28 | 1.28 | 0.0 | match | |
| Carrier held, sun → ring ratio (magnitude, reversed) | Willis equation (KHK Gear Technical Reference, planetary gear systems): −Zr/Zs | 3.5714 | 3.571 | -0.01 | match | |
| Carrier held: carrier reaction (N·m) | torque balance Ts+Tr+Tc=0 | 22.3214 | 22.3 | -0.1 | match |
Rack & Pinion Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Travel per pinion turn (mm) | KHK Gear Technical Reference (rack & pinion: travel per turn = π·m·z) | 125.6637 | 125.66 | -0.0 | match | |
| Linear speed (mm/s) | v=s·n/60 | 125.6637 | 125.7 | 0.03 | match | |
| Rack force (N) | F=2T/d | 500.0 | 500 | 0.0 | match | |
| Separating force (N) | Fr=F·tan20° | 181.9851 | 182 | 0.01 | match | |
| Turns for 500 mm stroke | stroke/s | 3.9789 | 3.98 | 0.03 | match | |
| Rack length (mm) | stroke+2p+40 (rule stated in notes) | 552.5664 | 553 | 0.08 | match | |
| Resolution, 200 steps direct (µm/step) | s/(steps·gr) | 628.3185 | 628.3 | -0.0 | match | |
| Resolution with 5:1 gearbox (µm/step) | s/(steps·gr) | 125.6637 | 125.7 | 0.03 | match |
Motor Speed & VFD Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Synchronous speed 4-pole 50 Hz (rpm) | IEC 60034-1 / ns=120f/p, T=9549P/n | 1500 | 1500 | 0.0 | match | |
| Slip (%) | IEC 60034-1 / ns=120f/p, T=9549P/n | 4.0 | 4 | 0.0 | match | |
| Rated torque 4 kW @1440 (N·m) | IEC 60034-1 / ns=120f/p, T=9549P/n | 26.525 | 26.5 | -0.09 | match | |
| Speed at 35 Hz, constant torque (rpm) | constant slip-speed approximation n=120f/p−Δn | 990 | 990 | 0.0 | match | |
| Power at 35 Hz (kW) | P=T·n/9549 | 2.75 | 2.75 | 0.0 | match | |
| Voltage at 35 Hz (V) | V/f constant | 280 | 280 | 0.0 | match | |
| Available torque at 75 Hz (N·m) | constant-power field weakening T=Tr·fb/f | 17.6833 | 17.7 | 0.09 | match | |
| Fan load at 35 Hz: load torque (N·m) | affinity law T∝n², slip ∝ torque | 13.306 | 13.3 | -0.04 | match | |
| Speed at 75 Hz with load at the field-weakening torque limit (rpm) | induction-motor slip ∝ T/Φ², Φ∝fb/f → slip 90 rpm | 2160.0 | 2210 | 2.31 | method difference | Page keeps slip ∝ torque at rated flux (documented n≈120f/p−Δn·T/Tr); with flux weakened to fb/f the slip at the same torque is (f/fb)² larger, so true speed ≈2160 rpm (page +2.3 %). |
| FAQ: 7.5 kW @1460 rpm rated torque (N·m) | IEC 60034-1 / ns=120f/p, T=9549P/n | 49.0531 | 49.1 | 0.1 | match |
Hydraulic Cylinder Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Push force @160 bar (kN) | Bosch Rexroth CDT3 data sheet RE 17032 (63/36: A1 31.17 cm², A3 20.99 cm², 160 bar push 49.87 kN / pull 33.58 kN, 18.7 L/min ≙ 0.1 m/s) | 49.87 | 49.9 | 0.06 | match | |
| Pull force @160 bar (kN) | Bosch Rexroth CDT3 data sheet RE 17032 (63/36: A1 31.17 cm², A3 20.99 cm², 160 bar push 49.87 kN / pull 33.58 kN, 18.7 L/min ≙ 0.1 m/s) | 33.58 | 33.6 | 0.06 | match | |
| Extend speed @18.7 L/min (mm/s) | Bosch Rexroth CDT3 data sheet RE 17032 (63/36: A1 31.17 cm², A3 20.99 cm², 160 bar push 49.87 kN / pull 33.58 kN, 18.7 L/min ≙ 0.1 m/s) | 100 | 100 | 0.0 | match | |
| Retract speed @20 L/min (mm/s) | v=Q/A2 (ISO 4413 basics) | 158.7778 | 159 | 0.14 | match | |
| Return flow retracting (L/min) | Q·A1/A2 | 29.697 | 29.7 | 0.01 | match | |
| Return flow extending (L/min) | Q·A2/A1 | 13.4694 | 13.5 | 0.23 | match | |
| Pump power @160 bar, 20 L/min, η 0.85 (kW) | P=p·Q/(600η) | 6.2745 | 6.27 | -0.07 | match | |
| Buckling utilisation, pinned–pinned (%) | Euler Fk=π²EI/(KL)², E 210 GPa, L=s+1.5D, S=3.5 (Rexroth buckling method) | 36.1004 | 36 | -0.28 | match | |
| Pressure needed for 40 kN (bar) | p=F/A1 | 128.3184 | 128 | -0.25 | match | |
| Regenerative extend force (kN) | F=p·A_rod | 16.286 | 16.3 | 0.09 | match | |
| Regenerative extend speed (mm/s) | v=Q/A_rod | 327.4793 | 327 | -0.15 | match |
Lead & Ball Screw Corrected
Corrected after the review:
- Added a thread-starts input: pitch = lead / starts for multi-start screws.
- ISO 2904 root diameter now uses the correct crest clearance for every pitch.
- Static friction assumption for self-locking (1.25 × μ) now stated.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default ball 16x5, F 2000 N: drive torque N·m, T = F·d2/2·tan(λ+ρ'), μ 0.005 | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eq. 8-1 (power screw torque) | 1.6724 | 1.672 | -0.02 | match | |
| Default ball 16x5: efficiency % | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eq. 8-4 (e = tanλ/tan(λ+ρ')) | 95.167 | 95.2 | 0.03 | match | |
| Default critical speed rpm, fixed-supported, dr 12.2 mm (λ2 15.1 incl. 0.8 SF) | THK ball screw catalogue, permissible rotational speed n = λ2·d1/L²·10^7 | 2878.4 | 2878 | -0.01 | match | |
| Default buckling limit N (η2 10.2 incl. 0.5 SF) | THK ball screw catalogue, permissible axial load P = η2·d1^4/L²·10^4 | 3530.7 | 3531 | 0.01 | match | |
| Default steps per mm (200 steps × 16 µsteps / 5 mm) | Definition | 640 | 640 | 0.0 | match | |
| Published: Shigley Example 8-1 (32 mm square thread, p 4, double start, f 0.08, F 6.4 kN): raising torque, thread only, N·m (page run as Tr with μ = 0.08·cos15° so ρ' = atan 0.08, starts 2) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Example 8-1 (TR = 15.94 N·m) | 15.94 | 15.937 | -0.02 | match | |
| Shigley Example 8-1: lead angle λ ° (dm 30 mm, l 8 mm) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Example 8-1 | 4.852 | 4.85 | -0.04 | match | |
| Tr16x4 μ 0.12, F 2000 N: drive torque N·m | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eq. 8-1 with ρ' = atan(μ/cos15°) | 3.0469 | 3.047 | 0.0 | match | |
| Tr30x6 root diameter d3 mm (d − P − 2ac, ac 0.5) | ISO 2904 (RoyMech trapezoidal table, d3 = 23.0) | 23.0 | 23 | 0.0 | match | |
| Tr8x1.5 root diameter d3 mm (ac 0.15) | ISO 2904 (d3 = 6.2) | 6.2 | 6.2 | 0.0 | match | |
| Tr40x7 root diameter d3 mm (ac 0.5) | ISO 2904 (d3 = 32.0) | 32.0 | 32 | 0.0 | match | |
| Tr8x8 P2 (4 starts): lead angle ° (d2 = 8 − 2/2 = 7) | ISO 2904 d2 = d − P/2; λ = atan(Ph/(π d2)) | 19.991 | 19.99 | -0.01 | match |
Block & Tackle Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default 200 kg, 4 parts, η 0.96, pulled down from top block: pull N | Sheave-friction (lead-line) method: W = P·Σηᵏ, Crosby "How to figure line parts" LF = Kᴺ(K−1)/(Kᴺ−1), η = 1/K | 542.45 | 542 | -0.08 | match | |
| Default top anchor load N (W + P) | Statics | 2503.8 | 2504 | 0.01 | match | |
| Default rope to pull m (4 × 2 m) | Kinematics | 8.0 | 8 | 0.0 | match | |
| Default friction loss % (1 − MA/n = 9.61 %, page shows whole %) | Energy balance | 9.61 | 10 | 4.06 | match | Within display rounding of the page value. |
| Pull-up from moving block, 4 parts: pull N (Σηᵏ, k = 0..3) | Sheave-friction (lead-line) method: W = P·Σηᵏ, Crosby "How to figure line parts" LF = Kᴺ(K−1)/(Kᴺ−1), η = 1/K | 520.75 | 521 | 0.05 | match | |
| Pull-up from moving block: top anchor load N (W − P) | Statics | 1440.6 | 1441 | 0.03 | match | |
| 6 parts pulled down: pull N | Sheave-friction (lead-line) method: W = P·Σηᵏ, Crosby "How to figure line parts" LF = Kᴺ(K−1)/(Kᴺ−1), η = 1/K | 376.18 | 376 | -0.05 | match | |
| 8 parts over carabiners (η 0.5): real mechanical advantage (0.996, shown to 2 decimals) | Sheave-friction (lead-line) method: W = P·Σηᵏ, Crosby "How to figure line parts" LF = Kᴺ(K−1)/(Kᴺ−1), η = 1/K | 0.9961 | 1 | 0.39 | match | |
| Published: Crosby lead-line factor, roller-bearing sheaves K 1.04, 4 parts (LF 0.2755): pull for 1000 kg, η = 1/1.04 | Sheave-friction (lead-line) method: W = P·Σηᵏ, Crosby "How to figure line parts" LF = Kᴺ(K−1)/(Kᴺ−1), η = 1/K | 2701.6 | 2702 | 0.01 | match | |
| Published: Crosby lead-line factor, bronze-bushed sheaves K 1.09, 6 parts (LF 0.2225): pull for 1000 kg, η = 1/1.09 | Sheave-friction (lead-line) method: W = P·Σηᵏ, Crosby "How to figure line parts" LF = Kᴺ(K−1)/(Kᴺ−1), η = 1/K | 2186.1 | 2186 | -0.0 | match | |
| 4 parts + 2:1 stage on the hauling line: pull N (MA = 3.6157 × (1 + η)) | Statics of compound tackle with η per sheave | 276.76 | 277 | 0.09 | match |
Bolt Torque Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default M10 8.8, K 0.20, 75 % proof: tightening torque N·m | T = K·F·d (Shigley eq. 8-27); proof strengths ISO 898-1 / SAE J429; stress areas ISO 898-1 / ASME B1.1 | 50.46 | 50.5 | 0.08 | match | |
| Default clamp force kN (0.75 × 580 MPa × 58.0 mm²) | T = K·F·d (Shigley eq. 8-27); proof strengths ISO 898-1 / SAE J429; stress areas ISO 898-1 / ASME B1.1 | 25.23 | 25.2 | -0.12 | match | |
| Default bolt stretch mm (F·L/(E·As), E 205 GPa, grip 30) | Hooke's law | 0.06366 | 0.064 | 0.53 | match | |
| Default hand force N at 300 mm wrench | Statics | 168.2 | 168 | -0.12 | match | |
| Published: Fastenal Grade 5 3/8-16, 75 % proof, K 0.20: clamp load lbf (4940) | Fastenal Torque-Tension chart for A307/Gr5/Gr8 (crafter.fastenal.com Torque-Tension_Chart_for_A307_Gr5_Gr8_Gr9.pdf) | 4940 | 4940 | 0.0 | match | |
| Published: Fastenal Grade 5 3/8-16 dry torque ft·lb (31) | Fastenal Torque-Tension chart | 31 | 30.9 | -0.32 | match | |
| Published: Fastenal Grade 5 3/4-16 UNF clamp load lbf (23 776) | Fastenal Torque-Tension chart | 23776 | 23712 | -0.27 | match | |
| M20 8.8 proof load kN (600 MPa above M16 × 245 mm²) | ISO 898-1 Table 5/7 | 147.0 | 147 | 0.0 | match | |
| M12x1.25 10.9, moly K 0.13, 75 %: torque N·m (As 92.1) | T = K·F·d (Shigley eq. 8-27); proof strengths ISO 898-1 / SAE J429; stress areas ISO 898-1 / ASME B1.1 | 89.438 | 89.4 | -0.04 | match | |
| SAE Grade 2 7/8-9: proof load kN (33 ksi = 228 MPa above 3/4 in × 298 mm²) | SAE J429 Grade 2 | 67.94 | 67.9 | -0.06 | match |
Compression Spring Corrected
Corrected after the review:
- Wire strength for stainless 302 and phosphor bronze now follows Shigley table 10-4 by wire diameter.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default rate N/mm (k = G d⁴/(8 D³ Na), G 81 GPa, Na 8) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eq. 10-9, Table 10-1 | 3.4722 | 3.472 | -0.01 | match | |
| Default stress at working length MPa (KB Bergsträsser) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eqs. 10-5, 10-7 | 343.63 | 344 | 0.11 | match | |
| Default allowable MPa (0.45 × 2211/2^0.145) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Tables 10-4, 10-6 | 899.81 | 900 | 0.02 | match | |
| Default surge frequency Hz (d/(2π Na D²)·√(G/2ρ)) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eq. 10-25 | 278.94 | 279 | 0.02 | match | |
| Published: Shigley Example 10-1 (No. 16 music wire d 0.037 in, OD 7/16 in, squared ends, 12.5 turns): rate lbf/in with Table 10-5 G 11.85 Mpsi (page G 81.0 GPa = 11.75 Mpsi) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Example 10-1; Table 10-5 | 4.116 | 4.1 | -0.39 | match | |
| Shigley Example 10-1: Ssy = 0.45·Sut ksi (Sut = 201/0.037^0.145 = 324 kpsi) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Example 10-1 | 145.89 | 145.6 | -0.2 | match | |
| Stainless 302 d 1 mm: allowable 0.35·Sut MPa (Sut 1867.0) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (Sut = A/d^m by wire size) and Table 10-6 (allowable 35 % Sut for stainless/nonferrous) | 653.45 | 653 | -0.07 | match | |
| Stainless 302 d 3 mm: allowable 0.35·Sut MPa (Sut 1546.8) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (Sut = A/d^m by wire size) and Table 10-6 (allowable 35 % Sut for stainless/nonferrous) | 541.38 | 541 | -0.07 | match | |
| Stainless 302 d 6 mm: allowable 0.35·Sut MPa (Sut 1236.2) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (Sut = A/d^m by wire size) and Table 10-6 (allowable 35 % Sut for stainless/nonferrous) | 432.67 | 433 | 0.08 | match | |
| Phosphor bronze d 0.5 mm: allowable 0.35·Sut MPa (Sut 1000.0) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (Sut = A/d^m by wire size) and Table 10-6 (allowable 35 % Sut for stainless/nonferrous) | 350.0 | 350 | 0.0 | match | |
| Phosphor bronze d 1.5 mm: allowable 0.35·Sut MPa (Sut 902.7) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (Sut = A/d^m by wire size) and Table 10-6 (allowable 35 % Sut for stainless/nonferrous) | 315.94 | 316 | 0.02 | match | |
| Phosphor bronze d 4 mm: allowable 0.35·Sut MPa (Sut 852.9) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (Sut = A/d^m by wire size) and Table 10-6 (allowable 35 % Sut for stainless/nonferrous) | 298.51 | 299 | 0.16 | match |
Extension Spring Corrected
Corrected after the review:
- Wire strength for stainless 302 and phosphor bronze now follows Shigley table 10-4 by wire diameter.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default rate N/mm (Na = Nb + G/E) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eqs. 10-9, 10-39 | 1.705 | 1.705 | 0.0 | match | |
| Default body stress MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eq. 10-7 | 338.29 | 338 | -0.09 | match | |
| Default hook bending σA MPa (C1 = C) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eqs. 10-34, 10-35 | 653.64 | 654 | 0.06 | match | |
| Published: Shigley Example 10-6 (hard-drawn d 0.035 in, OD 0.248 in, Nb 12.17, Fi 1.19 lbf): rate lbf/in (17.91, G 11.6/E 28.7 Mpsi; page uses 11.5/28.5) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Example 10-6 | 17.91 | 17.8 | -0.61 | match | |
| Shigley Example 10-6: body stress at 5.25 lbf ksi (L1 set so page force = 5.25 lbf) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Example 10-6 | 81.98 | 82 | 0.02 | match | |
| Shigley Example 10-6: hook torsion utilisation % (τB 78.6 ksi with r2 0.089 in, C2 5.09, / 0.40·Sut); page assumes C2 = 4 (tol 8 % covers that) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Example 10-6 | 74.24 | 78 | 5.06 | method difference | Page has no r2 input and fixes C2 = 2r2/d = 4 (documented), giving (K)B 1.25 instead of 1.184, so hook torsion is about 5.6 % high (conservative). The hook bend radius r2 is now an input (default 2·d), so the Shigley case can be entered exactly. |
| Stainless 302 d 1 mm: wire Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (by wire size) | 1867.0 | 1867 | 0.0 | match | |
| Stainless 302 d 3 mm: wire Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (by wire size) | 1546.81 | 1547 | 0.01 | match | |
| Stainless 302 d 6 mm: wire Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (by wire size) | 1236.19 | 1236 | -0.02 | match | |
| Phosphor bronze d 0.5 mm: wire Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (by wire size) | 1000.0 | 1000 | 0.0 | match | |
| Phosphor bronze d 1.5 mm: wire Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (by wire size) | 902.69 | 903 | 0.03 | match | |
| Phosphor bronze d 4 mm: wire Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table 10-4 (by wire size) | 852.87 | 853 | 0.02 | match |
Torsion Spring Corrected
Corrected after the review:
- Wire strength for stainless 302 and phosphor bronze now follows Shigley table 10-4 by wire diameter.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default rate N·mm/turn (k' = d⁴E/(10.8 D Na), Na = Nb + (l1 + l2)/(3πD)) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eqs. 10-51, 10-52 | 470.73 | 471 | 0.06 | match | |
| Default bending stress MPa (Ki inner fibre) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eqs. 10-43, 10-44 | 323.77 | 324 | 0.07 | match | |
| Default wound inside Ø mm (D' = D·Nb/(Nb + θ') − d) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eq. 10-54 | 10.6469 | 10.65 | 0.03 | match | |
| Published: Shigley Example 10-8 (music wire d 0.072 in, OD 19/32 in, Nb 4.25, legs 1 in): Sy = 0.78·Sut ksi (229.6) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Example 10-8 | 229.6 | 229.2 | -0.17 | match | |
| Shigley Example 10-8: rate lbf·in/turn (E 28.5 Mpsi) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Example 10-8 | 29.188 | 29.2 | 0.04 | match | |
| Shigley Example 10-8: max static angle ° (θ' = Mmax/k') | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Example 10-8 | 93.1 | 93 | -0.11 | match | |
| Stainless 302 d 1 mm: allowable Sy = 0.61·Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Tables 10-4, 10-10 (61 % for stainless/nonferrous) | 1138.87 | 1139 | 0.01 | match | |
| Stainless 302 d 3 mm: allowable Sy = 0.61·Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Tables 10-4, 10-10 (61 % for stainless/nonferrous) | 943.55 | 944 | 0.05 | match | |
| Stainless 302 d 6 mm: allowable Sy = 0.61·Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Tables 10-4, 10-10 (61 % for stainless/nonferrous) | 754.08 | 754 | -0.01 | match | |
| Phosphor bronze d 0.5 mm: allowable Sy = 0.61·Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Tables 10-4, 10-10 (61 % for stainless/nonferrous) | 610.0 | 610 | 0.0 | match | |
| Phosphor bronze d 1.5 mm: allowable Sy = 0.61·Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Tables 10-4, 10-10 (61 % for stainless/nonferrous) | 550.64 | 551 | 0.07 | match | |
| Phosphor bronze d 4 mm: allowable Sy = 0.61·Sut MPa | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Tables 10-4, 10-10 (61 % for stainless/nonferrous) | 520.25 | 520 | -0.05 | match |
Bevel Gear Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default pinion cone angle ° (tan δ1 = sinΣ/(z2/z1 + cosΣ)) | Gleason / KHK | 26.5651 | 26.57 | 0.02 | match | |
| Default cone distance R mm | Gleason / KHK | 44.7214 | 44.72 | -0.0 | match | |
| Default tangential force kN at dm1 = d1 − b sinδ1 (1.186, shown to 0.01 kN) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) §13-15 bevel force analysis | 1.1856 | 1.19 | 0.37 | match | |
| Default pinion radial force kN (Wt tanφ cosγ) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) eq. 13-38 | 0.386 | 0.39 | 1.04 | match | Within display rounding of the page value. |
| Published: KHK Gleason example: ha1 | KHK Gear Technical Reference, Calculation of Gear Dimensions, Table 4.12 Gleason straight bevel example (m 3, z 20/40, α 20°, Σ 90°, b 22) | 4.035 | 4.035 | 0.0 | match | |
| Published: KHK Gleason example: hf1 | KHK Gear Technical Reference, Calculation of Gear Dimensions, Table 4.12 Gleason straight bevel example (m 3, z 20/40, α 20°, Σ 90°, b 22) | 2.529 | 2.529 | 0.0 | match | |
| Published: KHK Gleason example: θf1 | KHK Gear Technical Reference, Calculation of Gear Dimensions, Table 4.12 Gleason straight bevel example (m 3, z 20/40, α 20°, Σ 90°, b 22) | 2.15903 | 2.159 | -0.0 | match | |
| Published: KHK Gleason example: da1 | KHK Gear Technical Reference, Calculation of Gear Dimensions, Table 4.12 Gleason straight bevel example (m 3, z 20/40, α 20°, Σ 90°, b 22) | 67.218 | 67.218 | 0.0 | match | |
| Published: KHK Gleason example: da2 | KHK Gear Technical Reference, Calculation of Gear Dimensions, Table 4.12 Gleason straight bevel example (m 3, z 20/40, α 20°, Σ 90°, b 22) | 121.7575 | 121.758 | 0.0 | match | |
| Published: KHK Gleason example: di1 | KHK Gear Technical Reference, Calculation of Gear Dimensions, Table 4.12 Gleason straight bevel example (m 3, z 20/40, α 20°, Σ 90°, b 22) | 44.8425 | 44.843 | 0.0 | match | |
| Published: KHK example: Xb1 axial face width mm | KHK Gear Technical Reference, Calculation of Gear Dimensions, Table 4.12 Gleason straight bevel example (m 3, z 20/40, α 20°, Σ 90°, b 22) | 19.0029 | 19.003 | 0.0 | match | |
| Σ 60° shaft angle, 20/40: pinion cone angle ° | Gleason / KHK general shaft angle tan δ1 = sinΣ/(z2/z1 + cosΣ) | 19.1066 | 19.11 | 0.02 | match |
Press Fit Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Contact pressure, Ø40 H7/s6, min fit | Lamé (Shigley eq. 3-56), hand calculation | 19.69 | 19.7 | 0.05 | match | Checked by the developer; independent review pending (new calculator). |
| Torque capacity at min fit | μ·p·π·d·L·d/2 | 237.5 | 238 | 0.2 | match | Developer check. |
| Hub von Mises stress at max fit | σt = p(Do²+d²)/(Do²−d²), σr = −p | 234.2 | 234 | -0.1 | match | Developer check. |
| ISO 286 interference H7/s6 at Ø40 | ISO 286-2: s6 +43/+59, H7 0/+25 µm | 18 – 59 | 18 – 59 | 0 | match | Uses the verified fits calculator tables. |
Shaft Key Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Hub flank pressure, Ø40 12×8×50 form A, 300 N·m, KA 1.25 | Hand calculation | 164.5 | 164 | -0.3 | match | Developer check; independent review pending (new calculator). |
| Required key length | F/((h−t1)·0.9·Re) + b | 34.8 | 35 | 0.6 | match | Page rounds up to whole mm. |
| Key size by diameter | DIN 6885-1 | 12 × 8 | 12 × 8 | 0 | match |
Bearing Life Corrected
Corrected after the review:
- Single 40° angular contact bearings: P = Fr below e = 1.14 (the paired-bearing formula was used before); static load P0 = max(Fr, 0.5·Fr + 0.26·Fa).
- Angular contact exactly at e (Fa/Fr = 1.14): floating-point rounding could select the upper branch; the comparison now keeps it on P = Fr (found by an external review, effect 0.02 %).
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default 6205: L10h h ((14.8/2)^3 × 10^6/(60·1500)) | ISO 281:2007 (L10 = (C/P)^p, X/Y table for radial ball bearings), SKF catalogue | 4502.49 | 4502 | -0.01 | match | |
| Default e (f0·Fa/C0 = 0.897, f0 14; 0.272 shown as 0.27) | ISO 281 Table 4 interpolation | 0.2719 | 0.27 | -0.7 | match | |
| Default required C kN for 20 000 h | ISO 281 inverted | 24.329 | 24.3 | -0.12 | match | |
| Default static safety s0 (P0 = max(Fr, 0.6Fr + 0.5Fa)) | ISO 76 / SKF | 3.9 | 3.9 | 0.0 | match | |
| Published: JTEKT/Koyo example, 6308 (Cr 50.9, C0r 24.0 kN, f0 13.2), Fr 3.5, Fa 1.0 kN: equivalent load P kN (3.78; page fixes f0 = 14) | JTEKT bearing knowledge, applied calculation examples (jtekt.co.jp .../5-7000.html: X 0.56, Y 1.82, P 3 780 N) | 3.78 | 3.756 | -0.63 | match | |
| Angular contact 40° single, Fa/Fr = 1.13 (below e = 1.14): P kN, Fr 1 | SKF / NTN single-row angular contact 40° (B) catalogue: single or tandem P = Fr for Fa/Fr ≤ 1.14, P = 0.35Fr + 0.57Fa above; P0 = 0.5Fr + 0.26Fa, P0 ≥ Fr | 1.0 | 1 | 0.0 | match | |
| Angular contact 40° single, Fa/Fr = 1.15 (above e): P kN | SKF / NTN single-row angular contact 40° (B) catalogue: single or tandem P = Fr for Fa/Fr ≤ 1.14, P = 0.35Fr + 0.57Fa above; P0 = 0.5Fr + 0.26Fa, P0 ≥ Fr | 1.0055 | 1.005 | -0.05 | match | |
| Angular contact 40° single, Fr 1, Fa 3 (well above e): P kN | SKF / NTN single-row angular contact 40° (B) catalogue: single or tandem P = Fr for Fa/Fr ≤ 1.14, P = 0.35Fr + 0.57Fa above; P0 = 0.5Fr + 0.26Fa, P0 ≥ Fr | 2.06 | 2.06 | 0.0 | match | |
| Angular contact 7205 B, Fr 1, Fa 3: static safety s0 (P0 = 0.5 + 0.78 = 1.28 kN, C0 10) | SKF / NTN single-row angular contact 40° (B) catalogue: single or tandem P = Fr for Fa/Fr ≤ 1.14, P = 0.35Fr + 0.57Fa above; P0 = 0.5Fr + 0.26Fa, P0 ≥ Fr | 7.8125 | 7.81 | -0.03 | match | |
| Angular contact 7205 B, Fr 2, Fa 1 (below e): static safety s0 (P0 = Fr = 2) | SKF / NTN single-row angular contact 40° (B) catalogue: single or tandem P = Fr for Fa/Fr ≤ 1.14, P = 0.35Fr + 0.57Fa above; P0 = 0.5Fr + 0.26Fa, P0 ≥ Fr | 5.0 | 5 | 0.0 | match | |
| Tapered roller 30205 (C 37.4), Fr 4, Fa 2: P kN (0.4Fr + 1.6Fa) | SKF 30205 J2/Q: e 0.37, Y 1.6 | 4.8 | 4.8 | 0.0 | match | |
| Spherical roller 22208 E, Fr 5, Fa 1 (Fa/Fr 0.2 < e): P kN with SKF factors (Fr + Y1·Fa, Y1 2.4) | SKF 22208 E product data: e 0.28, Y1 2.4, Y2 3.6, Y0 2.5 (coolenbearings.com/skf/roller-bearings/spherical/22208-e) | 7.4 | 7.41 | 0.14 | match | Corrected after this review: spherical roller factors now follow the selected bearing (22208 E: e 0.28, Y1 2.41); previously generic e 0.25 / Y1 2.7 gave P 4 % high. |
Shaft Diameter Corrected
Corrected after the review:
- C45 normalised values set to EN 10083-2 for 16–100 mm bar (305/580 MPa).
- Bearing slope now checks the larger of the two bearings.
- Added a DE-Goodman fatigue check (Marin endurance limit, Kf/Kfs, required diameter) and labelled the static safety factor as a design stress including shock factors and keyway.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default torque N·m (9549 P/n) | Standard | 49.391 | 49.4 | 0.02 | match | |
| Default bending moment N·m (F a (L − a)/L) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table A-9-5 | 80.0 | 80 | 0.0 | match | |
| Default strength diameter mm (C45 305/580 MPa, keyway, Km 1.5, Kt 1.0) | ASME Code for Design of Transmission Shafting (Bhandari, Design of Machine Elements): d³ = 16/(π τ)·√((Km M)² + (Kt T)²), τ = 0.75·min(0.3Sy, 0.18Su) with keyway | 21.276 | 21.3 | 0.11 | match | |
| Default twist diameter mm (0.25°/m, G 81 GPa) | θ = T/(G J) | 34.541 | 34.5 | -0.12 | match | |
| Default safety factor at Ø35 (von Mises with Km, Kt, keyway 1/0.75) | Page method: σv = √(σb² + 3τ²)/0.75 | 7.558 | 7.56 | 0.03 | match | |
| Default twist at Ø35 °/m (shown to 0.01) | θ = T/(G J) | 0.2371 | 0.24 | 1.22 | match | Within display rounding of the page value. |
| Default deflection at load, Ø35 µm (F a² b²/(3 E I L), shown to 1 µm) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table A-9-6 | 34.48 | 34 | -1.39 | match | Within display rounding of the page value. |
| Published: ASME worked example (20 kW, 200 rpm, M 500 N·m, Km 1.5, Kt 1.0, keyway, τ 81 MPa → d 42.4 mm), rescaled to the page's C45 QT τ 87.75 MPa: d = 42.4·(81/87.75)^(1/3) | ASME Code for Design of Transmission Shafting (Bhandari, Design of Machine Elements): d³ = 16/(π τ)·√((Km M)² + (Kt T)²), τ = 0.75·min(0.3Sy, 0.18Su) with keyway; example from makeiteasyhub.com/design-of-shafts-2026-guide-formulas-materials-codes-and-examples | 41.303 | 41.3 | -0.01 | match | |
| C45 normalised yield MPa (EN 10083-2 +N, 16 < d ≤ 100 mm: 305) | EN 10083-2 (RoyMech Steel-10083 table) | 305 | 305 | 0.0 | match | |
| Overhung 1.2 kN at 100 mm beyond a 300 mm span: bending moment N·m (F·a) | Shigley's Mechanical Engineering Design 10th ed. (Budynas/Nisbett) Table A-9-10 | 120.0 | 120 | 0.0 | match | |
| 42CrMo4 QT, torque only, plain shaft, 7.5 kW 1450 rpm: strength diameter mm (τ = min(225, 180) = 180 MPa) | ASME Code for Design of Transmission Shafting (Bhandari, Design of Machine Elements): d³ = 16/(π τ)·√((Km M)² + (Kt T)²), τ = 0.75·min(0.3Sy, 0.18Su) with keyway | 11.18 | 11.2 | 0.18 | match |
Speeds & Feeds Corrected
Corrected after the review:
- Milling chip thickness now uses the mean chip thickness from the engagement angle (full slots were 11 % low on power).
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Default turning Ø50, Vc 220: spindle rpm | Sandvik Coromant formulas & definitions (turning: Pc = vc·ap·fn·kc/60 000; milling: Pc = ap·ae·vf·kc/(60·10⁶), hm from engagement angle; drilling: Pc = fn·vc·Dc·kc/240 000), kc = kc1·h^−mc | 1400.56 | 1401 | 0.03 | match | |
| Default feed rate mm/min (f·n) | Sandvik Coromant formulas & definitions (turning: Pc = vc·ap·fn·kc/60 000; milling: Pc = ap·ae·vf·kc/(60·10⁶), hm from engagement angle; drilling: Pc = fn·vc·Dc·kc/240 000), kc = kc1·h^−mc | 280.11 | 280 | -0.04 | match | |
| Default MRR cm³/min (Vc·ap·f) | Sandvik Coromant formulas & definitions (turning: Pc = vc·ap·fn·kc/60 000; milling: Pc = ap·ae·vf·kc/(60·10⁶), hm from engagement angle; drilling: Pc = fn·vc·Dc·kc/240 000), kc = kc1·h^−mc | 88.0 | 88 | 0.0 | match | |
| Default cutting power kW (kc1 1500, mc 0.25, h 0.2) | Sandvik Coromant formulas & definitions (turning: Pc = vc·ap·fn·kc/60 000; milling: Pc = ap·ae·vf·kc/(60·10⁶), hm from engagement angle; drilling: Pc = fn·vc·Dc·kc/240 000), kc = kc1·h^−mc | 3.2898 | 3.29 | 0.01 | match | |
| Default spindle torque N·m (Mc = Pc·30 000/(π n)) | Sandvik Coromant formulas & definitions (turning: Pc = vc·ap·fn·kc/60 000; milling: Pc = ap·ae·vf·kc/(60·10⁶), hm from engagement angle; drilling: Pc = fn·vc·Dc·kc/240 000), kc = kc1·h^−mc | 22.43 | 22.4 | -0.13 | match | |
| Worked example Vc 200 m/min: cutting power kW (2.99) | Sandvik Coromant formulas & definitions (turning: Pc = vc·ap·fn·kc/60 000; milling: Pc = ap·ae·vf·kc/(60·10⁶), hm from engagement angle; drilling: Pc = fn·vc·Dc·kc/240 000), kc = kc1·h^−mc | 2.9907 | 2.99 | -0.02 | match | |
| Drilling Ø10, Vc 80, fn 0.2, mild steel: cutting power kW (hex = fn/2·sin 59°) | Sandvik Coromant formulas & definitions (turning: Pc = vc·ap·fn·kc/60 000; milling: Pc = ap·ae·vf·kc/(60·10⁶), hm from engagement angle; drilling: Pc = fn·vc·Dc·kc/240 000), kc = kc1·h^−mc | 1.8481 | 1.85 | 0.1 | match | |
| Milling full slot Ø12, z 3, fz 0.05, ap 6, Vc 150: mean chip thickness mm (2fz/π) | Sandvik Coromant formulas & definitions (turning: Pc = vc·ap·fn·kc/60 000; milling: Pc = ap·ae·vf·kc/(60·10⁶), hm from engagement angle; drilling: Pc = fn·vc·Dc·kc/240 000), kc = kc1·h^−mc | 0.03183 | 0.032 | 0.53 | match | |
| Milling full slot: cutting power kW | Sandvik Coromant formulas & definitions (turning: Pc = vc·ap·fn·kc/60 000; milling: Pc = ap·ae·vf·kc/(60·10⁶), hm from engagement angle; drilling: Pc = fn·vc·Dc·kc/240 000), kc = kc1·h^−mc | 2.5434 | 2.54 | -0.13 | match | |
| Side milling Ø12, ae 3 (φ 60°): mean chip thickness mm (fz·(2ae/D)/φ) | Sandvik Coromant formulas & definitions (turning: Pc = vc·ap·fn·kc/60 000; milling: Pc = ap·ae·vf·kc/(60·10⁶), hm from engagement angle; drilling: Pc = fn·vc·Dc·kc/240 000), kc = kc1·h^−mc | 0.02387 | 0.024 | 0.54 | match | |
| Spindle cap: turning Ø10 at Vc 220 with 3000 rpm max: rpm | n = min(1000 Vc/(πD), nmax) | 3000 | 3000 | 0.0 | match | |
| Published rule: 0.5 in cutter at 500 SFM → 3820 rpm (RPM = 3.82·SFM/D); page run as milling Ø12.7 mm, Vc 152.4 m/min | Machinery's Handbook RPM = 12·SFM/(π D) | 3819.7 | 3820 | 0.01 | match |
Tap Drill Size Corrected
Corrected after the review:
- 6H minor-diameter tolerance for pitches 0.35–0.6 mm corrected to ISO 965-1 grade 6 (was grade 5).
- At the default 77 % engagement the calculator now gives the ISO 2306 / DIN 336 standard tap drills (M8 → 6.8, M12 → 10.2, M12×1.25 → 10.8 mm) when they fall inside the 6H tolerance.
- UNC/UNF minor diameter now labelled as an approximation of ASME B1.1 class 2B.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| M3 coarse cutting tap drill (77 %) = 2.5 mm | ISO 2306 / DIN 336 standard tap drill: M3 -> 2.5 mm | 2.5 | 2.5 | 0.0 | match | |
| M6 coarse cutting tap drill (77 %) = 5.0 mm | ISO 2306 / DIN 336 standard tap drill: M6 -> 5.0 mm | 5.0 | 5 | 0.0 | match | |
| M8 coarse cutting tap drill (77 %) = 6.8 mm | ISO 2306 / DIN 336 standard tap drill: M8 -> 6.8 mm | 6.8 | 6.8 | 0.0 | match | |
| M10 coarse cutting tap drill (77 %) = 8.5 mm | ISO 2306 / DIN 336 standard tap drill: M10 -> 8.5 mm | 8.5 | 8.5 | 0.0 | match | |
| M12 coarse cutting tap drill (77 %) = 10.2 mm | ISO 2306 / DIN 336 standard tap drill: M12 -> 10.2 mm | 10.2 | 10.2 | 0.0 | match | |
| M16 coarse cutting tap drill (77 %) = 14 mm | ISO 2306 / DIN 336 standard tap drill: M16 -> 14 mm | 14 | 14 | 0.0 | match | |
| M20 coarse cutting tap drill (77 %) = 17.5 mm | ISO 2306 / DIN 336 standard tap drill: M20 -> 17.5 mm | 17.5 | 17.5 | 0.0 | match | |
| M12x1.25 fine tap drill = 10.8 mm | ISO 2306 / DIN 336 standard tap drill: M12x1.25 -> 10.8 mm | 10.8 | 10.8 | 0.0 | match | |
| M8 6H D1 min = 6.647 mm | ISO 965-1/-2: M8 6H D1 6.647-6.912 mm | 6.647 | 6.647 | 0.0 | match | |
| M8 6H D1 max = 6.912 mm | ISO 965-1/-2: M8 6H D1 max 6.912 mm | 6.912 | 6.912 | 0.0 | match | |
| M10 6H D1 max = 8.676 mm | ISO 965-2: M10 6H D1 8.376-8.676 mm | 8.676 | 8.676 | 0.0 | match | |
| M24 6H D1 min = 20.752 mm | ISO 965-2: M24 6H D1 20.752-21.252 mm | 20.752 | 20.753 | 0.005 | match | |
| M3 6H D1 max = 2.599 mm (P0.5, TD1=0.140) | ISO 965-2: M3 6H D1 2.459-2.599 mm | 2.599 | 2.599 | 0.0 | match | |
| M10 8.5 mm drill gives 77 % thread | Machinery's Handbook % thread = (D-d)/(1.299P): (10-8.5)/(1.299*1.5)=77 % | 77 | 77 | 0.0 | match | |
| M8 forming tap drill 7.4 mm (65 %) | Forming-tap drill charts (OSG/Emuge): M8x1.25 -> 7.4 mm | 7.4 | 7.4 | 0.0 | match | |
| 1/4-20 UNC at 75 % -> #7 drill 0.2010 in | Machinery's Handbook tap drill table: 1/4-20 -> #7 (0.201 in) for 75 % | 0.201 | 0.201 | 0.0 | match | |
| 1/4-20 2B minor dia min 0.196 in (page 0.1959) | ASME B1.1 1/4-20 UNC-2B minor dia 0.196-0.207 in | 0.196 | 0.1959 | -0.051 | match | |
| 1/4-20 2B minor dia max 0.207 in, page uses ISO 6H band (method, tol 1.5 %) | ASME B1.1 1/4-20 UNC-2B minor dia max 0.207 in | 0.207 | 0.2063 | -0.338 | method difference | Page applies the ISO 965-1 TD1 band to UNC (documented approximation), giving max 0.2063 in vs 0.2070 in in ASME B1.1 (-0.3 %). |
| M8 blind hole depth 17.8 mm for 12 mm thread | Page worked example / rule 12 + 3P + 0.3d | 17.79 | 17.8 | 0.056 | match |
Bolt Circle (PCD) Corrected
Corrected after the review:
- 5-stud measuring tip corrected: 0.951·D is centre to centre, not back edge to centre.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| 5x112 hole-to-hole chord 65.832 mm | Machinery's Handbook: chord = D sin(180/n), 5 holes K=0.58779 | 65.832 | 65.832 | 0.0 | match | |
| 5x112 hole to farthest hole 106.52 mm (0.951 D) | D cos(90/n); 5-stud 0.951·D | 106.518 | 106.518 | 0.0 | match | |
| 12 holes on D10 chord 2.588 (K=0.25882) | Machinery's Handbook bolt-circle constant n=12: 0.25882 | 2.588 | 2.588 | 0.0 | match | |
| 6x139.7 opposite hole 139.7 / chord 69.85 | Machinery's Handbook n=6 K=0.5 | 69.85 | 69.85 | 0.0 | match | |
| Measured 65.83 mm on 5 studs -> PCD 112.0 | PCD = C / sin(180/n) | 112.0 | 112 | 0.0 | match | |
| 8 holes D100: hole 2 X = 35.355 | x = R cos(45°) | 35.355 | 35.355 | 0.0 | match | |
| Ligament 65.83-14 = 51.83 mm | c - hole dia | 51.83 | 51.83 | 0.0 | match | |
| Edge distance (150-112)/2-7 = 12 mm | geometry | 12 | 12 | 0.0 | match | |
| Inch: 4 holes on 4.5 in -> chord 3.182 in | Machinery's Handbook n=4 K=0.70711 | 3.182 | 3.182 | 0.0 | match |
Surface Roughness Ra Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Turning f0.2 r0.8: Ra 1.60 µm | Boothroyd/Shaw: Ra = f²/(18√3 r) = 1.604 µm | 1.604 | 1.6 | -0.249 | match | |
| Turning f0.2 r0.8: Rt 6.25 µm | Rt = f²/(8r) (Sandvik/Kennametal) | 6.25 | 6.25 | 0.0 | match | |
| Ra in µin = 63 | 1 µm = 39.37 µin | 63 | 63 | 0.0 | match | |
| Feed for Ra 0.8 with R0.8 = 0.141 mm/rev | f = √(18√3·r·Ra) | 0.1413 | 0.141 | -0.212 | match | |
| Ball Ø10, stepover 0.5: cusp 6.25 µm | h = R − √(R² − (s/2)²) (Sandvik/Machinery's Handbook) | 6.254 | 6.25 | -0.064 | match | |
| Ball-nose Ra ≈ cusp/4 vs arc-profile Ra = 0.2566·h (method, tol 3 %) | Arc profile: Ra = h·8/(18√3) = 1.605 µm | 1.605 | 1.56 | -2.804 | method difference | Page uses the rule of thumb Ra ≈ cusp/4 (1.563 µm); the exact circular-arc profile gives 0.2566·h = 1.605 µm, 2.6 % lower, documented as approximate. |
| Turning f0.1 r0.4: Ra 0.802 µm | Ra = f²/(31.18 r) | 0.8018 | 0.802 | 0.025 | match | |
| Inch: f 0.008 in/rev, r 1/32 in: Ra ≈ 66 µin | Ra = f²/(18√3·r) ·1e6 µin | 65.68 | 66 | 0.487 | match |
ISO Fits & Tolerances Corrected
Corrected after the review:
- K8 holes: upper deviation now uses the k4–k7 value plus Δ (K8 at Ø25 is +10/−23 µm).
- Added the ISO 286-2 special case for M6 at 250–315 mm (ES = −9 µm).
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Ø25 H7 ES = +21 µm | ISO 286-2:2010 table: H7 18-30 = +21/0 | 21 | 21 | 0.0 | match | |
| Ø25 g6 es = −7 µm | ISO 286-2:2010 table: g6 18-30 = −7/−20 | -7 | -7 | 0.0 | match | |
| Ø25 g6 ei = −20 µm | ISO 286-2:2010 table: g6 18-30 = −7/−20 | -20 | -20 | 0.0 | match | |
| Ø25 K8 ES = +10 µm | ISO 286-2:2010 table: K8 18-30 = +10/−23 | 10 | 10 | 0.0 | match | |
| Ø25 K8 EI = −23 µm | ISO 286-2:2010 table: K8 18-30 = +10/−23 | -23 | -23 | 0.0 | match | |
| Ø300 M6 ES = −9 µm (special case) | ISO 286-2:2010 table: M6 250-315 = −9/−41 | -9 | -9 | 0.0 | match | |
| Ø300 M6 EI = −41 µm | ISO 286-2:2010 table: M6 250-315 = −9/−41 | -41 | -41 | 0.0 | match | |
| Ø25 M7 EI = −21 µm (ES 0) | ISO 286-2:2010 table: M7 18-30 = 0/−21 | -21 | -21 | 0.0 | match | |
| Ø25 N7 ES = −7 µm | ISO 286-2:2010 table: N7 18-30 = −7/−28 | -7 | -7 | 0.0 | match | |
| Ø40 P7 ES = −17 µm | ISO 286-2:2010 table: P7 30-50 = −17/−42 | -17 | -17 | 0.0 | match | |
| Ø25 P6 EI = −31 µm | ISO 286-2:2010 table: P6 18-30 = −18/−31 | -31 | -31 | 0.0 | match | |
| Ø100 s6 es = +93 µm | ISO 286-2:2010 table: s6 80-100 = +93/+71 | 93 | 93 | 0.0 | match | |
| Ø150 r6 ei = +65 µm | ISO 286-2:2010 table: r6 140-160 = +90/+65 | 65 | 65 | 0.0 | match | |
| Ø40 c11 ei = −280 µm | ISO 286-2:2010 table: c11 30-40 = −120/−280 | -280 | -280 | 0.0 | match | |
| Ø25 H7/g6 max clearance 41 µm | ISO 286-1: ES − ei = 21 + 20 | 41 | 41 | 0.0 | match | |
| Ø25 H7/p6 max interference 35 µm | ISO 286-2: p6 18-30 = +35/+22 | 35 | 35 | 0.0 | match | |
| Ø25 H7/p6 shrink temperature 229 °C | ΔT = (i + 0.001D)/(αD) (Machinery's Handbook practice) | 228.7 | 229 | 0.131 | match |
Gearing & Differential Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| RPM at 110 km/h in 6th = 2917 | n = v·i·1e6/(60·πD), D = 634.3 mm (225/45R17) | 2916.9 | 2917 | 0.003 | match | |
| Top speed at 6500 rpm in 6th = 245 km/h | v = n/i·πD·60/1e6 | 245.1 | 245 | -0.041 | match | |
| 1st gear at redline = 51 km/h | v = n/i·πD·60/1e6 | 50.69 | 51 | 0.612 | match | |
| Wheel torque in 1st = 4139 N·m (η 0.90) | T·i·η | 4139.2 | 4139 | -0.005 | match | |
| Tractive pull 13 051 N | T_wheel / r (unloaded radius) | 13051 | 13051 | 0.0 | match | |
| Wheel speed at 110 km/h = 920 rpm | 1e6·v/(60·πD) | 920.0 | 920 | 0.0 | match | |
| Inner wheel 15 m turn = 872 rpm (Ackermann geometry) | n·(R − t/2)/R | 872.5 | 872 | -0.057 | match | |
| Outer wheel 15 m turn = 968 rpm | n·(R + t/2)/R | 967.6 | 968 | 0.041 | match | |
| mph: 70 mph in 6th = 2987 rpm | 1 mi = 1.609344 km | 2987.3 | 2987 | -0.01 | match | |
| Ring/pinion 41/10 -> 4.10: 3206 rpm at 110 km/h | i = 41/10 | 3206.3 | 3206 | -0.009 | match |
Tire Size Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| 205/55R16 -> 225/45R17 diameter +0.38 % | ISO 4000-1 size code: D = rim·25.4 + 2·w·AR | 0.38 | 0.38 | 0.0 | match | |
| Real speed at 100 km/h = 100.4 | v·D_new/D_old | 100.38 | 100.4 | 0.02 | match | |
| New diameter 634.3 mm (Tire Rack 24.97 in) | tire spec tables | 634.3 | 634.3 | 0.0 | match | |
| Ground clearance +1.2 mm | (D_new − D_old)/2 | 1.2 | 1.2 | 0.0 | match | |
| Sidewall 101.25 mm | 225·0.45 | 101.25 | 101.3 | 0.049 | match | |
| Revs per km 502 | 1e6/(π·634.3) | 501.8 | 502 | 0.04 | match | |
| 225/50R17 is +3.94 % | D = 656.8 mm | 3.94 | 3.94 | 0.0 | match | |
| Inch: 265/70R17 diameter 31.61 in (published 31.6 in) | Tire maker spec (BFGoodrich KO2 265/70R17: 31.6 in) | 31.61 | 31.61 | 0.0 | match | |
| Inch: revs per mile 808 for 225/45R17 | 1.609344e6/(π·634.3) | 807.6 | 807 | -0.074 | match |
Engine Displacement & Compression Corrected
Corrected after the review:
- Two-stroke trapped compression now uses the piston travel from exhaust closing to TDC; preset chambers resized accordingly.
- Steam MEP formula now shows the 0.85 diagram factor that was already applied.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Honda K20 86x86x4 = 1998 cc (published 1998 cc) | Honda K20A spec: 1998 cc | 1998.2 | 1998 | -0.01 | match | |
| Static CR 11.01:1 | CR = (Vs+Vc)/Vc, Vc = 49.91 cc | 11.008 | 11.01 | 0.018 | match | |
| Dynamic CR 9.68:1 (IVC 50° ABDC, rod 139) | slider-crank x(θ); DCR = (Vc + A·x)/Vc | 9.682 | 9.68 | -0.021 | match | |
| Mean piston speed 22.4 m/s at 7800 rpm | cm = 2·s·n/60 | 22.36 | 22.4 | 0.179 | match | |
| Chevy 350: 5733 cc | 4.000 in × 3.48 in × 8 = 350 ci = 5733 cc | 5733.5 | 5733 | -0.009 | match | |
| Chevy 350: 349.9 ci (published 350 ci) | GM small-block 350 spec | 349.9 | 349.9 | 0.0 | match | |
| V8 90° firing interval 90° | 720°/8 | 90 | 90 | 0.0 | match | |
| Porsche 3.6 flat-6: 3600 cc | Porsche 964 M64: 3600 cc | 3600.3 | 3600 | -0.008 | match | |
| Mazda 13B: 2 × 654 = 1309 cc (Mazda 1308 cc) | Wankel Vh = 3√3·R·e·B | 1308 | 1309 | 0.076 | match | |
| Honda CR125: 124.8 cc | Honda CR125R 54 × 54.5 mm = 124.8 cc | 124.8 | 125 | 0.16 | match | |
| CR125 trapped CR ≈ 8.5 (preset target, exhaust closing → TDC) | Blair, Design & Simulation of Two-Stroke Engines: TCR = (Vc + A·(port depth − deck))/Vc | 8.5 | 8.49 | -0.118 | match | |
| CR125 exhaust duration 172° (opens 94° ATDC) | 360 − 2·94 | 172 | 172 | 0.0 | match | |
| Steam launch: MEP 6.14 bar (10 bar g, 40 % cut-off) | Hyperbolic expansion MEP = p1·c·(1+ln 1/c) − pb, × 0.85 diagram factor (Rankine/Ripper) | 6.144 | 6.14 | -0.065 | match | |
| Steam launch: swept volume/turn 1359 cc (double acting) | (2A − A_rod)·s·n | 1359.4 | 1359 | -0.029 | match |
Horsepower & Torque Corrected
Corrected after the review:
- Wording of the power-band note corrected.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| 200 N·m @ 4500 rpm = 94.25 kW | P = T·n/9549 (SI definition, 60000/2π) | 94.248 | 94.2 | -0.051 | match | |
| = 126.4 hp (mechanical) | 1 hp = 745.7 W | 126.39 | 126.4 | 0.008 | match | |
| = 128.1 PS | 1 PS = 735.5 W | 128.14 | 128.1 | -0.031 | match | |
| At wheels with 15 % loss = 80.1 kW | P·(1−loss) | 80.11 | 80.1 | -0.012 | match | |
| Torque for 150 kW @ 6000 rpm = 238.7 N·m | T = 9549·P/n | 238.73 | 238.7 | -0.013 | match | |
| Speed for 100 kW, 200 N·m = 4775 rpm | n = 9549·P/T | 4774.6 | 4775 | 0.008 | match | |
| US: 300 lb·ft @ 5000 rpm = 285.6 hp | hp = lb·ft·rpm/5252 | 285.6 | 285.6 | 0.0 | match | |
| 200 N·m = 20.39 kgf·m (unit table) | 1 kgf·m = 9.80665 N·m | 20.394 | 20.4 | 0.029 | match | |
| K20-type curve: peak power 146.6 kW | piecewise-linear torque, max of T·n/9549 (independent calc: 7977 rpm, 175.5 N·m) | 146.61 | 146.6 | -0.007 | match |
Jet Engine & Gas Turbine Corrected
Corrected after the review:
- Concorde (Olympus 593) preset corrected twice: it now gives about 44 kN per engine at Mach 2 cruise, the value consistent with the published cruise SFC and fuel burn (the first correction used a 30 kN figure from an unreliable source).
- Afterburner fuel uses a mean cp of 1240 J/kg·K and 90 % combustion efficiency; J79 TSFC now within 10 % of the published figure.
- Accuracy note corrected: turbofan fuel consumption reads about 15–25 % high in this simple model (CFM56 0.42 vs 0.33–0.36 lb/lbf·h), so the ±10 % claim now applies to thrust and turbojets only.
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| J79 dry thrust vs GE J79-GE-17 52.8 kN (method, tol 6 %) | GE J79-17 rating: 11,870 lbf (52.8 kN) dry | 52.8 | 55.5 | 5.114 | method difference | Page 55.5 kN is +5 % above the rating: ideal design-point Brayton cycle with no bleed/cooling, within the ±10 % the notes state. |
| J79 AB thrust vs 79.6 kN (method, tol 4 %) | GE J79-17 rating: 17,900 lbf (79.6 kN) with afterburner | 79.6 | 82.3 | 3.392 | method difference | Page 82.3 kN is +3.4 %: design-point simplification (no bleed, ideal expansion). |
| J79 dry TSFC vs 0.84 lb/lbf·h = 23.8 g/kN·s (method, tol 10 %) | J79-17 published SFC 0.84 lb/(lbf·h) dry | 23.79 | 26 | 9.29 | method difference | Page 26.0 g/kN·s is +9 %; within the documented ±10 % model accuracy. |
| J79 AB TSFC vs 1.965 lb/lbf·h = 55.7 g/kN·s (method, tol 9 %) | J79-17 published SFC 1.965 lb/(lbf·h) wet | 55.66 | 50.9 | -8.552 | method difference | Page 50.9 g/kN·s is −8.6 %; afterburner modelled with mean cp 1240 and 90 % efficiency, within the documented ±10 %. |
| J79 dry jet velocity 707 m/s (independent re-implementation, Saravanamuttoo method) | Saravanamuttoo, Gas Turbine Theory ch. 3 cycle with page constants | 707.1 | 707 | -0.014 | match | |
| Concorde (Olympus 593) cruise thrust vs ~44 kN (10,000 lbf) | Wikipedia Olympus 593 (~10,000 lbf/44 kN per engine at M2.02); fuel-burn check 20 t/h ÷ (4 × 33.8 g/kN·s) ≈ 42 kN | 44.0 | 43.9 | -0.23 | match | Corrected after this review: the preset previously gave 30.2 kN (tuned to an unreliable 27,160 lbf figure). |
| Concorde cruise TSFC vs 1.195 lb/lbf·h = 33.8 g/kN·s (method, tol 11 %) | Olympus 593 Mk610 published cruise SFC | 33.85 | 37.2 | 9.897 | method difference | Page 37.2 g/kN·s is +10 %: no variable intake/nozzle modelling, at the edge of the stated ±10 %. |
| CFM56 take-off thrust vs 120 kN (27,000 lbf, -5B4) (method, tol 6 %) | CFM56-5B4 rating 27,000 lbf | 120.1 | 126.2 | 5.079 | method difference | Page 126.2 kN is +5 %: design-point model. |
| CFM56 take-off TSFC vs 0.33-0.36 lb/lbf·h (≈ 9.8 g/kN·s) | Jenkinson et al., Civil Jet Aircraft Design, engine data table: CFM56-5A1 0.33, -7B20 0.36 lb/lbf·h take-off | 9.77 | 11.9 | 21.8 | method difference | The constant-cp cycle model reads turbofan TSFC about 15–25 % high; the page now states this limitation (the earlier ±10 % claim was corrected). |
| CFM56 cruise TSFC vs 0.545-0.596 lb/lbf·h (≈ 16.1 g/kN·s) | Civil Jet Aircraft Design table: CFM56-5A1 0.596, -5C2 0.545 at 35,000 ft M0.80 | 16.1 | 19.9 | 23.6 | method difference | The constant-cp cycle model reads turbofan TSFC about 15–25 % high; the page now states this limitation (the earlier ±10 % claim was corrected). |
| PW127 shaft power vs 2,051 kW (2,750 shp) (method, tol 5 %) | P&WC PW127F take-off rating 2,750 shp | 2.051 | 2.14 | 4.339 | method difference | Page 2.14 MW is +4.4 %: design-point estimate. |
| T700 shaft power vs 1,410 kW (1,890 shp) (method, tol 9 %) | GE T700-GE-701C rating 1,890 shp | 1.41 | 1.53 | 8.511 | method difference | Page 1.53 MW is +8.4 %: no cooling/bleed losses, within the stated ±10 %. |
| T700 SFC vs 0.47 lb/shp·h = 0.286 kg/kWh (method, tol 9 %) | GE T700-GE-701C published SFC | 0.286 | 0.261 | -8.741 | method difference | Page 0.261 kg/kWh is −8.8 %, within the documented ±10 %. |
U-Joint & Driveshaft Verified
| What was checked | Reference | Expected | Calculator | Diff % | Verdict | Note |
|---|---|---|---|---|---|---|
| Single 10°: speed swing 3.06 % | Hooke: 1/cosβ − cosβ (Shigley / Mabie & Reinholtz) | 3.063 | 3.06 | -0.098 | match | |
| Single 10°: min output 2954 rpm | n·cosβ | 2954.4 | 2954 | -0.014 | match | |
| Single 10°: max output 3046 rpm | n/cosβ | 3046.3 | 3046 | -0.01 | match | |
| Single 10°: angle error 0.44° | tan Δmax = (1−cosβ)/(2√cosβ) | 0.4386 | 0.44 | 0.319 | match | |
| Single 10°: peak acceleration 3023 rad/s² | max of ω²·sin²β·cosβ·sin2θ/(1−sin²β cos²θ)² | 3022.7 | 3022 | -0.023 | match | |
| Single 10°: output torque max 203 N·m | T1/cosβ | 203.1 | 203 | -0.049 | match | |
| Z layout 10°/8°: output swing 1.11 % | two-joint kinematics, numerical (independent) | 1.106 | 1.11 | 0.362 | match | |
| Z layout 10°/10°, 90° phasing error: swing 6.12 % | 1/cos²β − cos²β | 6.124 | 6.12 | -0.065 | match | |
| Z layout 90° error: max 3093 rpm | n/cos²β | 3093.3 | 3093 | -0.01 | match | |
| Z layout 10°/10° in phase: intermediate 2954 rpm | n·cosβ | 2954.4 | 2954 | -0.014 | match |