how large to drill the hole for splined studs?

I want to drill an axle flange for splined studs.
How much undersize is the hole made so the spline on the stud digs in good?
It seems like the the hole need to be maybe .0020" smaller than the OD of the spline itself.

Does this sound right? I tried to measure the od of the top of the spline and the bottom of the valley and came up with .0020" difference.

The difference between too tight and too loose must be pretty close.

Thanks

 

Same size as the stud, you gotta get the threads thru the hole before it gets to the splines

 

I was looking at the studs behind the counter at Napa and some had a spline that was much larger od than the the threads and other that where close to the same size.

I was thinking somebody that does 9" axles and redrills them for chev patterns would be able to tell me.
thanks

 

Mike the o.d. of the serations,take a scrap piece of metal,drill a hole a 1/64 smaller,press it in,see if that works,If not try another hole 1/32 smaller.

 

gotta know the size of the spline portion. check a Machinery's Handbook

 

splines need to have a intense interference fit, i mike the diameter at the root of the seration (bottom of the grove) drill as close as i can to that dimension it will press in little harder but will not come out spin in the hole. and deburr the hole good before pressing

 

I was thinking that i should try one on a piece of scape.
Thanks

 

i find .020...that\'s 20 thousands....usually does it.

as you said , try it on some scrap first , your experience may vary

 

I used to pound in a lot of these! Whoever sells them to you should be able to give you the manufacturer's spec. I know my catalog always did. It beats gussing since there are some difficult ones to measure. I also drop in a tack weld on the back to help keep them still. Just make sure it is in a spot that you can grind off if you need to replace the stud later.