C110 COPPER HOGOUT

[OC_THE MCX]

In need of some advice. working on a piece of c110 copper about 6.5 x 19.35 x 1.750. A lot of it gets hogged out leaving islands and pockets. The first time I did this job, rough out all features leaving .05 an all walls and floors. When it came time to finish features to size, the part warped big time. We had to bend parts straight on an a large arbor press before we could re-machine finish passes and it warped a little more. what a nightmare!!! now, we have 100 parts to make!!!!! Has anyone had this problem before and will an anealing procces help? Thanks for any advise.

[Robert Ouellette]

rough them out and leave about .100" or so. then heat treat them. then finish. should be good that way. they should stay pretty stable.

[BernieT]

I think you need to 'stress relieve' them twice - both before and after roughing . Check with a heat treater but I believe 550 deg to 600 deg F for 1 hr would work nicely.

 

It's possible the 2nd stress relieve wouldn't be necessary ..........

 

In my experience, any wrought copper warps horribly when machined, unless stress relieved.

 

HTH

 

Good luck

 

 

[OC_THE MCX]

Ok guys, I'm taking your advise. We will stress-relief stock before we start, rough it out and if needed, a second stress-relief process. Thanks again

[BernieT]

[jeff]

Is it possible to buy slightly oversized stock and cut about 1/8" from all sides before you rough out the part?

that may help with the warping, but like others have said, stress relieving will surely help.

[Mic6]

Start cutting yet?

[OC_THE MCX]

Jeff, too late for that. material has been ordered cut to size. Mic6, have not started cutting yet. still waiting on delivery. This copper ingot is expensive before I even touch it !! Dont you guys just love jobs where you only have one chance to get it right???

 

 

[K2csq7]

Dont you guys just love jobs where you only have one chance to get it right???

 

There are other kinds??????????

[Mic6]

Mic6, have not started cutting yet. still waiting on delivery.

 

 

 

Keep us posted, pics if possible

[OC_THE MCX]

 

 

Mic 6, took these pics from 1st prototype run. drilling and tapping not done yet, checking part flatness.

[OC_THE MCX]