Files

T

davide 0908191ef3 add tolleranze-iso skill: ISO 286-1 tolerance and fit selection consultant

Complete ISO 286-1 skill for mechanical designers covering:
- Fit selection (clearance/transition/interference) with intake protocol
- IT grades 1–16 with required machining processes for bores and shafts
- Full functional elements reference: rolling bearings, gears, keys (DIN 6885),
  Seeger rings, cylindrical pins, plain bushings, lip seals, splined profiles,
  couplings, linear guides (14 sections total)
- Fundamental deviations table (bores A–ZC, shafts a–zc, Ø1–500 mm)
- Surface roughness Ra correlation by IT grade
- Python calculator (scripts/calculate_fit.py) with JSON data files for exact
  clearance/interference computation and formatted fit data sheet output
- Visual input support: analyses attached drawings, sketches, photos
- Description ≤ 1024 chars, written in English for optimal trigger accuracy

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

2026-03-23 12:20:53 +01:00

4.6 KiB

Raw Permalink Blame History

Fundamental Deviations — Numerical Values (ISO 286-1)

How to Read This File

Example: Ø50 H7/k6

Diameter range: 50 mm → rows "30–50" and "50–80"
Bore H7: lower deviation EI = 0, upper deviation ES = +25 µm (IT7 for Ø50)
Shaft k6: lower deviation ei = +2 µm, upper deviation es = ei + IT6 = +2 + 16 = +18 µm
Max clearance = ES − ei = 25 − 2 = +23 µm → clearance
Min clearance = EI − es = 0 − 18 = −18 µm → interference → Transition fit, in practice predominantly with slight interference

Bore Fundamental Deviations (uppercase) — Lower Deviation EI (µm)

Bore	1–3	3–6	6–10	10–18	18–30	30–50	50–80	80–120	120–180	180–250
B	+140	+140	+150	+150	+160	+170	+180	+200	+210	+230
C	+60	+70	+80	+95	+110	+120	+130	+145	+160	+170
D	+20	+30	+40	+50	+65	+80	+100	+120	+145	+170
E	+14	+20	+25	+32	+40	+50	+60	+72	+85	+100
F	+6	+10	+13	+16	+20	+25	+30	+36	+43	+50
G	+2	+4	+5	+6	+7	+9	+10	+12	+14	+15
H	0	0	0	0	0	0	0	0	0	0
JS	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2
K (6–8)	0	+2	+2	+2	+2	+3	+4	+4	+4	+5
M (6–8)	−2	−4	−6	−7	−8	−9	−11	−13	−15	−17
N (6–8)	−4	−8	−10	−12	−15	−17	−20	−23	−27	−31
P (6–7)	−6	−12	−15	−18	−22	−26	−32	−37	−43	−50
R	−10	−15	−19	−23	−28	−34	−41	−51	−63	−77
S	−14	−19	−23	−28	−35	−43	−53	−71	−92	−100
U	−18	−23	−28	−33	−41	−53	−66	−90	−109	−130

Note

: For H, ES = EI + IT = 0 + IT (e.g. H7/Ø50: ES = +25 µm)

Shaft Fundamental Deviations (lowercase) — Upper Deviation es (µm)

Shaft	1–3	3–6	6–10	10–18	18–30	30–50	50–80	80–120	120–180	180–250
b	−140	−140	−150	−150	−160	−170	−180	−200	−210	−230
c	−60	−70	−80	−95	−110	−120	−130	−145	−160	−170
d	−20	−30	−40	−50	−65	−80	−100	−120	−145	−170
e	−14	−20	−25	−32	−40	−50	−60	−72	−85	−100
f	−6	−10	−13	−16	−20	−25	−30	−36	−43	−50
g	−2	−4	−5	−6	−7	−9	−10	−12	−14	−15
h	0	0	0	0	0	0	0	0	0	0
js	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2	±IT/2
k	0	+1	+1	+1	+2	+2	+2	+3	+3	+4
m	+2	+4	+6	+7	+8	+9	+11	+13	+15	+17
n	+4	+8	+10	+12	+15	+17	+20	+23	+27	+31
p	+6	+12	+15	+18	+22	+26	+32	+37	+43	+50
r	+10	+15	+19	+23	+28	+34	+41	+51	+63	+77
s	+14	+19	+23	+28	+35	+43	+53	+71	+92	+100
u	+18	+23	+28	+33	+41	+53	+66	+90	+109	+130

Note

: For h, ei = es − IT = 0 − IT = −IT (e.g. h6/Ø50: ei = −16 µm)

Worked Examples

Example 1: Ø30 H7/g6

Bore H7 (Ø30, range 18–30):

EI = 0
ES = EI + IT7 = 0 + 21 = +21 µm
Bore: Ø30 +0.021/0

Shaft g6 (Ø30, range 18–30):

es = −7 µm
ei = es − IT6 = −7 − 13 = −20 µm
Shaft: Ø30 −0.007/−0.020

Clearances:

Max clearance = ES − ei = +21 − (−20) = +41 µm (0.041 mm)
Min clearance = EI − es = 0 − (−7) = +7 µm (0.007 mm)
→ Guaranteed clearance fit ✓ (lubricated precision guide)

Example 2: Ø50 H7/p6

Bore H7 (Ø50, range 30–50):

EI = 0, ES = +25 µm

Shaft p6 (Ø50, range 30–50):

es = +26 µm
ei = +26 − 16 = +10 µm

Interferences:

Max interference = es − EI = +26 − 0 = +26 µm (0.026 mm)
Min interference = ei − ES = +10 − 25 = −15 µm → clearance possible?

⚠️ This is a transition fit at Ø50! For guaranteed interference on Ø50, p6 gives ei − ES = 10 − 25 = −15: there is still a possibility of clearance. For guaranteed interference on Ø50 use r6 or s6.

→ Always verify numerical values for your specific diameter before finalising the drawing.

4.6 KiB Raw Permalink Blame History Unescape Escape