[Rusty13]

I need to have a couple parts fabricated and would appreciate input (I know next to nothing about metal machining). Any comments you have about material, finishing, modifying sizing to increase ease of machining, etc would be appreciated

The part I want to replace is steel (mild steel I suspect). The part is one side of a press that squeezes thin plastic and embosses it with a pattern. I want to replace the part in order to change the pattern.

The part is 122 x 20 x 30mm (aprox 4.75" x .75" x 1.25"). The height of the pattern on the part is 0.5mm tall (aprox .02")

I was hoping to have 1mm as the spacing in and around each raised piece in the pattern.

The surface of the pattern needs to be a flat plane. The pattern itself doesn't require an excessive level of accuracy - I'm assuming +/- .005" is reasonable to achieve?

Anything obvious that I should change to make machining easier? Standard units instead of metric maybe?

New pattern design (in mm) :




Original design:

[mflux_gamblej]

That will require tooling that most people won't keep in their shop. Go to mcmaster carr and lookup a 0.025" diameter endmill and see the price - then figure you might break a few. Someone with an EDM sinker could do that part for you - will be pretty pricey though. Good luck! If its gonna be an EDM project, steel won't be trouble. On a mill with those fancy small / easily breakable endmills its going to be better in aluminum.

[PJRitz]

It would probably be easier to mill with a slitting saw than a tiny endmill.

[RICHARD ZASTROW]

Ganged slitting saws for spaces and end mill or? to remove larger areas as PJRitz suggested. Used that method for serrated sealing dies in packaging machines.

Dick Z

[easymike29]

Relatively simple on a surface grinder. Somewhat time consuming. I would guess about 3-5 hours.

Gene

[Rusty13]

Thanks so much for the input. Based on that input I've:

- Adjusted dimension to best match to inches
- Adjusted the pattern based on 1/32" cuts from a metal slitting saw
- Resized pattern to fit on a stock 1/2" x 1" bar

Would there be a huge difference in cost/time between using 4140 and tool steel?
Any other comments?

Revised drawings:

[Rusty13]

I've done a final redesign based on the feedback.

If anyone is interested in fabricating these parts please let me know. I've just posted in the RFQ section in Canada and the USA (these should easily be shipped to Vancouver BC or Bellingham Wa).

Thanks again.
Rusty13

[awerby]

I'd say find someone with a horizontal mill. While making all those slots with a 1/32" endmill would be a nightmare on a vertical mill, it would be a piece of cake for a 1/32" kerf saw-blade type cutter in a horizontal mill.

Andrew Werby
www.computersculpture.com

[victorofga]

try to post on the tormach section..
a slitting saw the solution, however with cnc some migth takes on this..
timeconsuming, however easy to programming

you can find endmills at bitsbits.net or ebay...