The parts are shafts and couplings and have to fit bearings so I know some of the tolerances are going to be plus and some are minus. Could anyone offer general tolerance iso 2768 pdf simpler explaination of what I am seeing. One of the external shafts has a f9 while most of the other shafts have a h9 or h6.
A keyway has a N9 and the internal keyway has a j59. One of the internal bores has a M6. Most of the tolerances use lower case but some are upper case, I dont know if that makes a difference or not. Anyone know of a source for a simpler explaination of these that is in english?
The internal bore with M6 sounds like it`s threaded M6 x 1. Are the other tolerances not in Machinery Handbook? A bearing catalog will have a table with the tolerances. Basically, a small letter is the tolerance for a shaft and a captial letter is the tolerance for the hole. The M6 is the tolerance for that bore and is not a thread designation. 1000 is the tolerance in mm. 6 is for a schaft for example 25.
Thank you for that link, it doesnt offer everything I need but it does come closer than I had gotten by myself. I do have a shaft dimention that is not on the chart, it is for an OD 12mm h9. The chart skips over h9 for some reason. 009 if I read the chart correctly. 000 It would pay to check that with one of the other members. This link often gets put up with questions about ISO tolerance. The same MHB, gives me a slight difference to your h6.
Yes I got that too, but there are a lot of other tolerances that are not listed in my handbook. I just need to find a better source and I am hoping to not have to buy all the standards if I dont have too. I am just quoting the job and I am still waiting on some answers from the company I got the drawings from. I thought I could get a head start and educate myself at the same time. One shaft has a dim 25mm f9, a bore is marked M6 and to me that seems super tight, more than the part requires but I am hoping I just read the chart wrong. There are keyways and snap ring grooves and I just cant seem to find all the information I was hoping for in the MHB but I will keep searching. I have an ISO Tolerance book my company published, but it looks like it is not available any longer.
Is the M6 hole tolerance also 25mm? By the way, DIN 2768mk is a general tolerance table that provides the tolerances for anything that is not toleranced on the drawing, it does not refer to the diameter tolerances you are asking about. You can find info on the DIN 2768 at the link below. I just found the tolerances on the keyway, and no the M6 is on a 47mm bore which makes me wonder why so tight a tolerance, I was hoping I was reading it wrong.
I didnt see where you got the -17 from, at least that would allow me to have a little more room to work. I didnt think that correct for a shaft but that is what is in my book. Now you know why I wanted to ask others, this doesnt really add up. I really do need some reference that I can point to for these just in case there is any problem I need some printed version of these tolerances. I will check out the general one you mentioned. An M6 tolerance on a 47mm bore should be -4 to -20 according to my book. I’m using a book published by FAG Bearings that lists the complete tolerance range for each designation, I don’t have my Machinerys Handbook here to check and see what is in there.
Are you sure you are not looking at H tolerance tables? The capital H is for holes and all of those are 0 to a plus number. After you have used it a bit, these tolerances get easier. I wish I had a copy of the complete tables I could email you, the following link is mounting and dismounting catalog that has tables in the back, but does not have all of what you are looking for. If I find some time tomorrow, I will see if I can scan my tables and send them to you. Thank you all for your help, this has been quite an education so far but it does seem to follow a pattern and I am glad I have decided to follow up with it.
If anyone knows of a techical reference that might be more inclusive and useful I will gladly pay a little for the effort to copy and email or mail it to me. I was thinking of a Text book? Something some engineer in training might use or perhaps a machining student might have access to? I have several booklets on GDT and similar subjects but nothing on the european or DIN standards. Even if it was in German I could work with the tables or have one or two locals translate for me. I haven’t used it, but the demo looks interesting.
6 million unique visitors over the last year, Practical Machinist is the most visited site for metalworking professionals. Practical Machinist is the easiest way to learn new techniques, get answers quickly and discuss common challenges with your peers. Eng-Tips’s functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail. Working for a very global oriented company, we use ISO for all Global Dimensioning and Tolerancing standards for our drawings. After receiving training per the ASME Y14.
5 standard, it has been a constant state of confusion for me while trying to understand our standard tolerancing schemes that we have on our prints. Time and time again I have seen prints that outright conflict with ASME, and most often they lack very important controls, and sometimes datums, to insure proper function of the parts. Every time I question or comment about this, I am always told that our general tolerance callout of ISO 2768 covers anything not stated. Recently, there has been a push to provide further development to our Design Engineers and Technical Drawers in the area of making and understanding drawings made to the ISO standards.