Metric Thread clearances?

[wchowe]

I am designing some equipment that uses some special sized metric threads (103mm). I want the two mating pieces to turn freely by hand (jam nut, adjusting nut, etc). Is there any documentation that defines which tolerance and grade to use when you want a specific outcome (like hole/pin fit tolerances)? I am guessing I want to specify a tolerance/grade for the nut of "6H" and the matching bolt "6g". I believe the standard fit tolerance will work in my situation. I just wasn't sure if I should go larger "6G6g"? I don't want to loose a fit either. Suggestions?

Thanks
Bill

 

[CoryPad]

No documentation comes to mind. 6H and 6g should work fine.

 

[rmw]

The only documentation I have ever seen is in Spanish. And I bought it in Madrid so I have no idea where I would try to find it again if I needed to replace it.

rmw

 

[wchowe]

Does anyone know where to find the actual tolerances and dimensions for 6g 6H thread?

Thanks
Bill

 

[TVP]

ISO 965-1 explains the metric thread tolerance scheme. ISO 965-3 shows the exact values for the various thread sizes and tolerances. For example, for external thread size between 90 and 180 mm, 2 mm pitch, the 6g tolerances are as follows:

pitch diameter
es - 38 mm
ei - 188 mm

major diameter
es - 38 mm
ei - 318 mm

 

[juergenwt]

wchowe - Do yourselves a big favor and get a copy of DIN 13.
You will find out among other things that a combination of 6H/6h is never used - and for a good reason. You use 6H/4h or 6H/6g. Also why are you going with M103 x 2 ? M102 x 2 and M105 x 2 are standard. Have your company order a booklet for DIN13 in English from:

http://www.beuth.de/cn/J-6BFB49F662...bGV2ZWw9dHBsLWhvbWUmbGFuZ3VhZ2VpZD1lbg**.html

Lot's of info here:

http://mdmetric.com/fastindx/inxtst.htm

 

[juergenwt]

Looks like the first http for Beuth is nor working. Try here:

http://www.beuth.de/cn/bGV2ZWw9dHBsLWhvbWUmbGFuZ3VhZ2VpZD1lbg**.html

Still having a problem. It looks like they are working on it and the web site should be available shortly. If not google : Beuth- Verlag - English.