Press Fit / Reaming Sanity check Please

[rodm1]

Run a test piece first reamers do ream over and under when new. If over run it backwards then put a stone to the cutting edge to reduce the size.

 

[SLK001]

You shouldn't have any problems pressing steel into aluminum. Given your numbers, your press might be a little on the "light" side. I would shoot for around 0.002" undersize for my hole on both of the sizes. Chamfer your steel slightly to ease starting the press. You might have to rig up a pressing jig (a piece of metal with a hole of the finished stud size) to help keep the press straight.

 

[Boswell]

You might have to rig up a pressing jig

I like that. I will be pressing 1.5" pins through a .5" plate with .5" sickout on each side. A jig could help ensure they pins start well and perpendicular but could also ensure proper depth. I guess a jig could be as simple as a piece of aluminum that is .5" thick and a clearance hole for the pin. I could just seat the "chamfered" pin in the hole, slide the jig over the pin and then press until the press head hits the top of the jig.

I used GWizard to recommend the clearance size for a press fit. I'll be doing some tests this next week when I can get into the shop to see how the fit is. If too loose, I could either add some Loctite 638 or try a smaller reamer. There will be very little mechanical force on the pins once in place. I have a small arbor press and I also have a 12ton hydraulic press.

 

[Winegrower]

I could just seat the "chamfered" pin in the hole, slide the jig over the pin and then press until the press head hits the top of the jig.

Bingo! Just right. Also, I have a set of over/under reamers - plus or minus 0.001 from nominal. In aluminum, it works well to use a 0.001 press fit. 0.002 under works too, just needs more tonnage.

 

[Boswell]

Thanks Winegrower. I am not going to be able to run a test until later this week. then I'll drill/ream some test holes and press in some pins to see what I like best.