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Machined Groove In Sheet Metal

Machined Groove In Sheet Metal

Machined Groove In Sheet Metal

(OP)
Hello All,
I came up with a design, but I'm not sure if this particular machining operation will cause issues. We have a 1/8" (3.175mm) thick sheet of aluminum 5052, and we need to machine an o-ring groove 1.96mm deep. Would this be a costly and difficult procedure?
Thanks!

RE: Machined Groove In Sheet Metal

It depends.  You can definitely cut the groove, but the cost is likely going to depend upon the design of your part.

Dan

www.eltronresearch.com
Dan's Blog

RE: Machined Groove In Sheet Metal

This would be an easy job for a CNC router. It could nest the parts, cut the grooves and the holes.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them.  Old professor

RE: Machined Groove In Sheet Metal

You must do all the cutting on a mill or router.
If someone gets the bright idea of punching any of the holes or shearing the edges, the part will distort enough to screw up your o-ring depth tolerances.

You will probably get calls about the part for as long as it's in production.

 

Mike Halloran
Pembroke Pines, FL, USA

RE: Machined Groove In Sheet Metal

"If someone gets the bright idea of punching any of the holes or shearing the edges, the part will distort enough to screw up your o-ring depth tolerances."

Clearly the words of someone who has little or no knowledge of compound pierce and blank tools or fine blanking tools.

Whilst a router or CNC mill is probably the best way to go do not rule out a press tool, especially a fine blank tool if quantity allows for this within the budget.
 

RE: Machined Groove In Sheet Metal

Agree with Ajack1.  As an example, the parts to a proverbial Swiss watch are fineblanked.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: Machined Groove In Sheet Metal

In defense of the punching/shearing comment, to shear the blank and punch on a turret machine, then mill the groove while constraining the part flat could be a bad idea. The strains induced in the punching process would be relieved and make it difficult to hold tolerance.

Fineblanking along with semi-piercing might be a good way to process the part, provided that the quantities justify the purchase of the die. The OP does not state quantities to be produced: it may only be one.

RE: Machined Groove In Sheet Metal

What's the width of the groove?  If really small, you might have to go around two or three times, which could get expensive.

Software For Metalworking
http://closetolerancesoftware.com
 

RE: Machined Groove In Sheet Metal

Mike's Statement is correct, Punching will be half sheared & half tear in the material, a fine blanking die can be improved but will have sharp burrs,a secondary punch can improve the holes.

Please do not be condescending just state the facts how a punch
will not leave sharp edges. or what can be done to improve punching. I have a few years experience with punching, I am sure
I don't know it all.

secondly It's not wise to criticize an other one statement. milling or routing will definitely be a much improvement but will be expensive for high volume parts.
 but can easily be done for R&d or low volume.
Depending on the quality & quantity there can be a compromise.

Mfgenggear

RE: Machined Groove In Sheet Metal

(OP)
Thanks for all the input, everyone. This will be a low volume part, and we will carry forward with a CNC router/mill for the machining operation. Hopefully we will be at higher volumes later and a fine blanking punch will be used.

RE: Machined Groove In Sheet Metal

So you think "acid etching" is an option?

RE: Machined Groove In Sheet Metal

11echo (Petroleum)
Chem etching is a solution ( A strong alkaline is used for aluminum.). However it would take longer than a CNC mill or router.
The part would also have to be masked, and chem etching is notorious for eching at different rates unless a chem-etch quality material is used.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them.  Old professor

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