- 98% satisfied customers
- 72h delivery
- 30 dni na zwrot
Thread plug gauge M8x0.75 6H
13181
€19.42 tax inc.
Net price: €15.79
Description
THREADM8x0.75
TOLERANCE6H
STANDARDISO 1502
MATERIALTool steel
M8x0.75 6H GO/NO-GO thread plug gauge
Internal thread gauge according to PN-ISO 1502:1998
| TECHNICAL DATA | |
|---|---|
| Thread type | ISO metric (M) — fine pitch |
| Thread size | M8x0.75 |
| Thread pitch | 0.75 mm (fine) |
| Tolerance class | 6H |
| Gauge type | GO / NO-GO |
| Material | Tool steel, hardened |
| Hardness | 58-62 HRC |
| Standard | PN-ISO 1502:1998 |
| Manufacturer | Varel |
1
GO end — longer thread with a full profile. It is screwed in by hand through the full length of the hole.
2
Handle engraved M8x0.75-6H — size and tolerance class of the inspected hole.
3
Red ring — identifies the NO-GO end.
4
NO-GO end — shorter thread with a truncated profile. It checks only the pitch diameter, so it is allowed to enter by 2 turns.
Thread plug gauge M8x0.75 6H provides the fastest check of a threaded hole — without a micrometer or calculations. The end GO must enter by hand along the full thread length, while the end NO-GO must stop after no more than 2 turns, counted when unscrewing. GO enters, NO-GO does not — the hole meets class 6H.
This is the most frequently inspected group in the shop — bolt holes in housings, brackets, and machine subassemblies. In series production, the gauge detects a dull tap faster than visual inspection or trying a randomly selected bolt. The fine pitch of 0.75 mm provides a shallower profile and less clearance than the coarse pitch of 1.25 mm. The gauge fits only the thread M8x0.75 — M8 with a 1.25 mm pitch requires a separate gauge. For reference: the internal thread minor diameter M8x0.75 is 7.188 mm, while the gauge checks the pitch diameter, which is the dimension halfway up the thread profile.
Operating principle: GO / NO-GO
How to check an internal thread correctly
1
The GO end is screwed in by hand, without force, along the full length of the M8x0.75 thread.
2
The NO-GO end stops after no more than 2 turns — turns are counted when unscrewing.
3
The GO end passed, the NO-GO end stopped — the hole is within class 6H.
Thread inspection in 3 steps
1 GO end (longer thread)
Screwing into the thread — must enter
2 NO-GO end (red)
Screwing into the thread — no more than 2 turns
✓ Acceptable thread
Tolerance: 6H OK
If the end GO enters, and the end NO-GO does not enter — the thread meets the requirements of class 6H according to PN-ISO 1502:1998
GO end (passes)
No color marking — it has a longer thread and GO marked on the handle. It checks minimum internal thread dimensions. It must screw in freely along the full thread length. If it does not enter — the thread is undersized (the workpiece requires rework).
NO-GO end
Marked with a red ring. Checks maximum thread dimensions. It must not screw in more than 2 threads, with turns counted when unscrewing the gauge, not when screwing it in. If it goes farther — the thread is too loose and the part does not meet the tolerance class. For a thread 3 turns long or shorter, the NO-GO end must not pass all the way through.
✓ Thread acceptable — GO enters the full length, NO-GO stops.
✗ Thread too tight — GO does not enter the hole.
✗ Thread too loose — NO-GO enters more than 2 turns.
Tolerance class 6H for an M8x0.75 thread
Comparison of tolerance classes for an M8x0.75 internal thread
Comparison of classes 4H, 5H, 6H and 7H
Basic pitch diameter D2 for the thread M8x0.75 is 7.513 mm. In classes designated H, this is also the minimum dimension — the tolerance extends upward only.
| Class | D2 nominal [mm] | D2 permissible [mm] | Tolerance zone | Application | Status |
|---|---|---|---|---|---|
| 4H | 7.513 mm | 7.513 – 7.598 mm | 0.085 mm | Precision | |
| 5H | 7.513 mm | 7.513 – 7.619 mm | 0.106 mm | Close | |
| 6H | 7.513 mm | 7.513 – 7.645 mm | 0.132 mm | Standard | THIS PRODUCT |
| 7H | 7.513 mm | 7.513 – 7.683 mm | 0.170 mm | Coarse |
The full range of class 6H for the thread M8x0.75 is 0.132 mm: from 7.513 to 7.645 mm. Class 6H corresponds to a typical nut and a standard machine tap — it is selected for class 6g bolts. Classes 4H and 5H reduce clearance where the thread guides a component; 7H leaves an allowance for electroplating. The values in the table refer to pitch diameter D2, not the tap drill diameter.
Set contents and storage
Set contents and gauge storage
INCLUDED:
| ✓ | M8x0.75 6H GO/NO-GO thread plug gauge |
| ✓ | Size marking on the plug |
STORAGE:
| ✓ | Store in a dry place, in its case |
| ✓ | Protect against dropping — impact damages the thread |
| ✓ | Apply rust-preventive oil periodically |
Frequently asked questions
6H is the most commonly used internal thread tolerance class according to ISO 965-1. The digit 6 specifies the tolerance grade (zone width), and the letter H indicates the tolerance zone position (lower deviation = 0). Class 6H provides a standard fit with class 6g bolts.
The end GO (GO, with the longer thread) must enter freely along the full thread length. The end NO-GO (NO-GO, red) should not screw in more than 2 turns (counted when unscrewing). Both conditions must be met simultaneously for the thread to be considered acceptable according to PN-ISO 1502:1998.
Gauge wear is checked by periodic measurement at intervals based on usage intensity (ISO 1502, clause 7.2.1); the standard specifies neither the number of measurements nor a fixed interval. A worn gauge gives false positive results — the NO-GO end starts entering the thread. The gauge should be verified periodically using setting gauges.
Product accessories
Machine Tap M8X0.75 ISO 529 D HSSE Fra
Reference: 0000009840 In stock > 10 items
€6.32
€7.77 brutto
Reviews
No customer reviews for the moment.
Shipping
All orders are delivered by courier company GLS. For orders exceeding 369 PLN gross shipping is FREE
| Courier GLS | Przelew24 / Prepayment | 14,76 zł gross | Delivery time 1 working day |
| Courier GLS | Cash on delivery | 17,26 zł gross | Lead time 1 working day |
Recommended for you
Viewed products
This website uses its own and third-party cookies to improve our services and show you advertising related to your preferences by analyzing your browsing habits. To give your consent to its use, press the Accept button.
Cookie preferences
Functional cookiesTechnical
Functional cookies are strictly necessary to provide the services of the shop, as well as for its proper functioning, so it is not possible to refuse their use. They allow the user to browse through our website and use the different options or services that exist on it.
Advertising Cookies
These are cookies that collect information about the advertisements shown to users of the website. They can be anonymous, if they only collect information about the advertising spaces shown without identifying the user, or personalised, if they collect personal information about the user of the shop by a third party, for the personalisation of these advertising spaces.
Analytics cookies
Collect information about the user's browsing experience in the shop, usually anonymously, although sometimes they also allow the user to be uniquely and unequivocally identified in order to obtain reports on the user's interests in the products or services offered by the shop.