EDM: What Metal & Thickness Is Best for Go/No Go Gage?

[racookpe1978]

Simple problem, but there appears to be no "boilerplate" answer.

I need to make a few (less than 15) Go/No Go gages to verify pipe weld reinforcement heights and offset dimensions.

Critical dimensions are the gage "tips" (+/- 0.030, +/- 0.060, +/- 0.090 and +/- 0.125 inches) that protrube from both sides of the small plate. Tolerances need to +0.000, minus 0.004.

Overall gage size will be 2 inches long 1-1/4 high, similar to the common fillet weld gages, but overall size and thickness is not very important.

They are intended to be stiff plates, but should be easy (cheap) to machine or EDM cut - I am assuming of either stainless steel or aluminum. If stainless, I assume 0.045 or 0.062 thick; if Al, then 0.060 thick.

....

Boss wants to know if they can be EDM cut, or me to recommend the best (least expensive) machining method.

Any recommendations or corrections? (PDF file of the gage outline is available.)

 

[mfgenggear]

without seeing the drawing
I would say approx. 1/4 -3/8 thickness

A-2 harden tool steel
wire edm to make, fit the contour of the pipe.

MfgEngGear

 

[racookpe1978]

See proposed outline in attached file.

 

[MikeHalloran]

You might also find laser or waterjet cutters who'll take a crack at it.

Don't miss the opportunity to include a trademark or logo in the handle.

I'd go at least 1/8" thick in either material.

Put it up for bid on mfg.com.



Mike Halloran
Pembroke Pines, FL, USA

 

[Troy2601]

I dont think that a lazer or waterjet has the capability to hold a +.000 -.004 tolerance. so i would also recomend using A2 Tool Steel and Grinding all guages on a serface grinder atleast for a square datum then harden them to a 54-56 RC and use wire EDM to finish. may be able to come up with a decent way to fixture them to cut multiple at once to reduce runtime or increace accuracy.