AL part is getting nickel plated...

[Mic6]

The boss told me this part was going to get 1mil thick nickel plating. I only imagine the kind of hell this will give my 2-56 STI threads. I'm experimenting(development part) by making my NO-GO(PD.0989) go with a real smooth fit. GO(.0976) so now I'm .0013 oversize. Seeing as I'm getting .001 plating per side, theoretically I should comp my tool out .0007. Theory shmeary. The nickel is for corrosion resistance so they want everything plated(no plugging, plus these holes are getting inserts. I'm going to shoot for a little looser fit and once engineering sees that these tiny threads have issues with the plating, maybe we plug them. This part also has 1/4-28, .750-20, 8-32STI and 10-32 STI.

 

Any words of experience out there?

[strabe]

It's all on the plating shop to be sure that they don't underplate or overplate. I don't know how well the nickel will flow in that size of a hole. You might find the bigger holes will be okay and the small ones out of spec. My advise is talk to the platers and see what they think they can give you.

 

Good luck.

[McLaren]

Buildup on threads is 4x, not 2x.

[Guest]

Buildup on threads is 4x, not 2x.

 

+1

 

upper and lower on the "v" and both sides

[McLaren]

Opps, I guess I should elaborate.

 

Plating thickness is measured perpendicular to the face of the thread, but the pitch diameter is measured on axis.

[Newbeeee™]

Potential nightmare here....The guys are correct at the build up, but it depends upon whether the holes are through or not.

Plating doesn't like blind holes, and you end up with build up at the top, with usually nothing at the bottom. It is better with larger holes, but I wouldn't think you'd get anything to worry about with your hole size IF they're blind.

Normally, the holes would be plugged and the WTI's put in with an assy paste (similar to molykote but I can't for the life of me remember the name, apart from it begins with J). This helps prevent any galvanic corrosion between the stainless insert and the ally housing.

[Mic6]

Thanks for the input! I guess we shall see what happens. The 2-56 STI holes are thru.