Clamshell Battery Contact Repair


Seeking additional comments on design and interest. This is an alpha prototype. I will be trying to form radius better. Will probably need to make a pressing fixture.


Thanks, it is looking great. For an alpha prototype it is looking very professional and good quality. The Sheet metal thickness also looks fine and strong, would go thinner or thicker. Is it possible to control the dimensions without too much extra work so that it stays flush to the surface, especially doesn’t stay higher than the rubber pads? Also IMHO Some color similar to the calculator body or even black would look much better.


How feasable would be to have some sort of plastic block on the battery side of the clip to make it nice and flush with the case? Does the round end of the clip interfere in any way with the hinge?


I can get it black oxide coated. I need to follow up with my plating guy.

I think I can get it to lay flush more. If I bend the radius in a press. I need to work on that tool.

Plastic could be added I suppose, but it would cost.

Edited: 2 Mar 2012, 11:30 p.m.


Could this metal clam fit over the top of the existing battery door? I've still got the door for my 28S but the clam-shell case won't hold it anymore.

- Pauli


It could if bent differently. I would think it would slide around a lot.


I think I am going to make it wider, at least a the top, to slide into the exiting groove. One of the challenges I had was using a sheet stock that was strong enough. The original metal contact is very thin and I don't think it would have been strong enough and I had a hard time getting some. This material I had.

This material is nearly the same thickness of the groove width. It fits snugly. With a little filing, it will fit.

What do you think?

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