What am I doing wrong cutting aluminum?

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tomb18
Posts: 77
Joined: Tue Oct 27, 2015 3:03 am

Re: What am I doing wrong cutting aluminum?

Post by tomb18 » Fri Jan 29, 2016 5:01 am

sgth0mas wrote:
tomb18 wrote:Hi,
Its a 1/16 flat end mill from drillman.
Thanks
Number of flutes? HSS or Carbide? Coating?
It's 2 flute carbide. No coating

tomb18
Posts: 77
Joined: Tue Oct 27, 2015 3:03 am

Re: What am I doing wrong cutting aluminum?

Post by tomb18 » Fri Jan 29, 2016 5:06 am

Hmm, I suppose it could be tool holding but I have some really fine results.
Just wish I could find some concrete examples on how to evgrave small letters on aluminum. Tools, speeds, depths etc. Seems hard to come buy so I have to experiment.
So far the best is 25" / min, 0.004 depth, drill to 0.010 deep with a stick font. The Tool used for this is 1/4" 90 degree drill bit mill, carbide double flute.
So many choices

WillAdams
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Re: What am I doing wrong cutting aluminum?

Post by WillAdams » Fri Jan 29, 2016 12:01 pm

My results from the wiki:

1/8" thick 6061-T6 alu. Plate[59] Feed 215mm Depth 0.2mm Plunge 27mm Bits 1/8" 2 flute carbide and V-bit

http://www.shapeoko.com/forum/viewtopic ... 731#p53729
Shapeoko 3XL #0006 w/Makita RT0701 Router w/0.125″ and ¼″ Elaire precision collets
Nomad 883 Pro #596 (bamboo)

sgth0mas
Posts: 101
Joined: Sat Dec 12, 2015 5:57 pm

Re: What am I doing wrong cutting aluminum?

Post by sgth0mas » Fri Jan 29, 2016 1:56 pm

Even if the results seemed to go well the first time its likely not helping your tool life. running that slow overheats the tool and dulls the blade. It can also cause chip rewelding from the heat. With machines that use routers as the spindle, the rpms cant drop low enough to run at such low feed rates unfortunately.

Most manufacturers publish their recommended feed and speed data online. Its very dependent on the particular cutter you are using as well as your machine. If you cant find the exact cutter, ive always gone to onsrud and looked at their data for the same geometry and material cutter.

BUT...most of the feed and speed charts assume you have more horsepower than a desktop machine, so use the low end of the range and run your first few jobs at a derated number until youre comfortable.

I did a quick write up on the process here:

https://www.linkedin.com/pulse/machinin ... k-articles

Btw...if you havent used them yet, o flutes are awesome in plastic, but spiral up cuts still work well.

stuarttaylor00
Posts: 36
Joined: Mon Oct 19, 2015 4:06 am

Re: What am I doing wrong cutting aluminum?

Post by stuarttaylor00 » Sun Jan 31, 2016 10:45 am

After breaking a few 1/8 bits and giving up on that size, I ended up settling on:

3 flute1/4" End Mill at 600mm\min, 200mm\min plunge, around 14,000rpm, 0.2mm DOC, and achieved great results in 1/2" 6061 aluminium.

I got an awesome finish, and good looking chips. I'll start pushing harder to see where the limit is. I only have cheap 1/8" bits so will leave them to wood and stick with 1/4"
Shapeoko 3 #1095 - Aluminium wasteboard, homing switches, Modified Z plate, Makita 700 router
Flashforge Dreamer Dual extruder 3D printer

2013 Ducati 848 Evo ;)

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