Fastest way to CNC sheet aluminum?

Have a question or want to show off your project? Post it! No Registration Necessary.  Now with pictures!

Threaded View
I'm making 10 flat plates (approx 3.5" x 6.5") with a curved
outline out of 0.063" thick aluminum sheet. This plate fits inside
another assembly and I need to hold a tolerance of +/- 0.010".
For my prototype I cut out the plate with a 1/8" flat endmill in 3
passes of 0.021" on my Taig CNC mill. If my production rate
increases I will look into sending the work out for water jet, but in
the meantime I'll be using the Taig mill (if you don't know the Taig
mill, it's a small hobby mill with not much HP).

I'm wondering if a faster cutter is available - perhaps a roto-zip
cutter? I'd like to cut the plates in one pass if possible (don't
know if the Taig motor can handle that). I'd be OK doing minor clean-
up of the edges with emery cloth if it cuts fast.

Any ideas?

Regards,
Ed Ferguson

Re: Fastest way to CNC sheet aluminum?


Ed wrote:

Quoted text here. Click to load it
Get a 1/8" solid catbide end mill.  It can do .062" aluminum if you can
keep the
chips from piling up.  You may want an air blast to clear the chips.

It can defintely cut that thickness.  I had an accident with one, and it
went
plowing through 1/8" aluminum at 40 IPM without breaking!  You can
try 2-flute, but I often use a 4-flute as it gives twice as many cutting
edges
per rev.  You'd probably want lots of speed on the spindle for that size
cutter.

Jon


Re: Fastest way to CNC sheet aluminum?
Ed wrote:
Quoted text here. Click to load it

 Any through holes in the part that could be used as jig pin holes?

 Ten thou sounds well within the realms of the possible for a router
table with a decent carbide bit with a pilot bearing on it. Make a
master from 1/4" plate, then run the pilot bearing on that while the
cutter cleans off the sheet stock.

 I suspect that a little parafin canning wax and a heat gun could serve
as a replacement fot the pins, though it would slow down the production
rate. Still way faster than the Taig, I'd bet.

 63 thou stock would be dead easy for a wood router.

 Cheers
  Trevor Jones

Re: Fastest way to CNC sheet aluminum?
Trevor,

Good input.  The part has a 3" dia hole and I've pre-drilled two
fixture holes inside the large hole for securing to my mill plate.  I
have a router table and router - I may give that a try with a carbide
cutter.  My router certainly has more HP than my Taig spindle.

Regards,
Ed Ferguson

Quoted text here. Click to load it

Re: Fastest way to CNC sheet aluminum?
Ed wrote:
Quoted text here. Click to load it

Why waterjet? Lasers are faster and cheaper for that kind of work, and you'll
get more parts per sheet than with milling.

Check out where I work:

<http://www.thelasershop.com

If you can attach an AutoCad file, or FAX a print, we can quote it.

David

Re: Fastest way to CNC sheet aluminum?
For waterjet cutting speeds, you may want to download the abrasivejet
feed rate calculator at:

http://www.waterjets.org

Specifically:

http://www.waterjets.org/abrasive_waterjet_software_downloads.html

0.010" tolarance is super easy to get.  For such thin material, you
might even consider cutting a stack of parts in one pass.  There is a
list of waterjet job-shops at the above link also.

As far as being the "fastest way", I can't say.  This material is so
thin that lots of methods could cut it quickly.  I would consider
lasers, waterjet (abrasivejet), and stamping.  Which works best will
depend on you needs and quantities.

- Carl.

snipped-for-privacy@aol.com (Ed) wrote in message
Quoted text here. Click to load it

Site Timeline