n40x2x18x8h specs...please

[tulmkr]

I have to wire edm this spline in a part, and cant find the spline data. I know i have to cut it per din 5480, but im not used to metrics. My edm gear program generates alot of info, but i dont know what to do with the 8h which i believe refers to the class of fit. How do i find the tolerances of this spline. I am cutting the internal only, and i dont have the shaft in my possesion. I have to get it right the first time. Any help is appreciated. The tooth thickness and space width seem to be at odds with each other as well. I also cant find what the minor is supposed to be.

 

[TVP]

First, are you aware that you can obtain an English-language version of DIN 5480-1 for $185 from Global Engineering Documents:

http://global.ihs.com/doc_detail.cf...30&input_doc_number=DIN 5480&input_doc_title=

Second, I am not an expert on splines, so I can only tell you that N40 is the hub reference diameter, 2 is the module, 18 is the number of teeth, and 8h is the side fit requirement. h means no deviation, and tolerance class 8 has the following requirements

T_G total tooth thickness (or space width) tolerance = 0.090 mm

T_act actual tooth thickness (or space width) tolerance = 0.056 mm

T_eff effective tooth thickness (or space width) tolerance = 0.034 mm


Table 7 of DIN 5480-1 contains the information that you need.

 

[gearcutter]

'8f' refers to the shaft only. The internal tolerance is capitalized '8F'. You can not mate an '8f' with a '8H' so don't assume that the shaft tolerance you've been given can be used for the hub. You need to find out what the fit tolerance, your customer requires, is.
The standards will give a guide as to how to work this out.
If my customer can not give me this information then I will usally give them a easy sliding fit. In this case it would be something like 9H.
I can sell you the DXF to cut this spline.
Contact me via the link below.

Ron Volmershausen
Brunkerville Engineering
Newcastle Australia

http://www.aussieweb.com.au/email.aspx?id=1194181

 

[gearcutter]

I made a mistake in my previous post.
"You can not mate an '8f' with a '8H'" should have read; You can not mate an '8f' with a '8F'.

Ron Volmershausen
Brunkerville Engineering
Newcastle Australia

http://www.aussieweb.com.au/email.aspx?id=1194181

 

[spigor]

It's very probable all the data you need for your EDM program to cut it right, assuming it is a n40x2x18x9H internal spline, is as follows:

DP=25,4/2=12,7
PA=30
T=18
BD=31,117 mm
ID=36 +0,1 mm
OD=40 +0,52 mm
space width=4,181 +0,026/+0,07 mm