Need Help!- Calling all Gurus

[csatom]

Hello All...I work for a company that machines (among other things) connecting rods for combustion engines. Recently, some of our rod customers have requested that we provide a "profile" within the wrist pin bore of the rod. I have done a fair amount of research, but am interested in getting the perspective and opinions of some of you who might have something to contribute.

From the research I have done thus far...Im thinking that a jig grinder might do the trick for prototype work. For low to mid volume work, probably a machine with a U-axis. The problem I have is that those are really the only two options I can see. We are attempting to prove out the jig grinding method currently, but it doesnt seem practical for more than a few parts. We priced out u-axis systems...they are right in the $70k range, not including the machine.

The problem I have with the u-axis (aside from the cost) is that the manufacturers claim that their u-axis' can create the profile, but they have no way of measuring the results, and cant guarantee it. I know it is being done in production, but we are a small shop, dealing in low volumes. I need a viable, economical solution. Any thoughts or suggestions are greatly appreciated.

I have attached a print showing the profile with dimesnions. Please keep in mind that the dimensions are in METRIC.

BTW...anyone know of a shop in the Detroit area with a machine capable of producing this?

Thanks

Tom

[csatom]

Sorry...Not sure what happened. Here is the attachment

[underthetire]

Depending on the volume, You could do them on a lathe. You would need to build a fixture to locate them, and to balance the opposite site of the rod to keep a good finish, but it would work. Of coarse if it's a huge rod out of a tractor or something, it may not be feasible.

[fizzissist]

CNC lathe bore job. Special chucking fixture. Very easy.

[RICHARD ZASTROW]

Those are metric dimensions aren't they? .005mm would equal .0002". Pretty tight contour tolerances for a lathe. Just sayin'.

Dick Z

[Hennessy]

ya so I am no Guru but ..... if dia A is +\- .005 mm .... and you are supposed to be .005 mm on the profile to the bore... what the hell is b=(A+0.010)+\-.005 mm ? .... honestly to me is looks like a bore re-leaf that an "e" went overboard on .... I would ask if you can modify the profile.... the fit needs to be there but that profile is ????

If I am wrong let me know ... I like learning..

Hennessy