excited about aluminum

[twelchPTM]

SO when we first set up our bot I tried my hand at some aluminum, nothing fancy just some mounting plates for casters, and it was a NIGHTMARE!!!

Just to day while working on a project, I came to a point where I thought, "This we be so easy if I just had two pieces that looked like blah blah blah". Then I looked up and I say her in her shimmering blue greatness, but I hesitated remembering my last experience with aluminum, quickly shaking of the fear I set to work, 5 minutes of design and 15 minutes of machining with my handy can of WD-40 and I had the parts I needed perfectly tailored to fit my project and I was done!

No pics, see the two little plates are not the point of the story (plus do you really want to see my square with a hole in it). The point is that now I am bouncing off the walls with excitement realizing that yes, YES, YES I can cut aluminum. If anyone has any nifty projects they can share for me to find inspiration I would be greatful.

And before we go there, to those would reply "just do a search"... I have and I am but there are a lot of hits and it never hurts to ask.

[Brady Watson]

Single flute spiral-O bit 1.2-1.5 XY, 0.7 Z @ 13-15000 RPM is the baseline. Always use the shortest tool for the job & never ever plunge straight down or drill - tool will get destroyed as AL melts onto tip. Always ramp into cut using smooth or spiral ramp.

No coolant other than dust collection required. No lube required. True for material up to about 3/8" thick - over this and other methods & tricks are required. Harder alloys machine better than softer ones.

-B

[tomwillis]

Brady,
I have not experimented yet with using tabs in Alum - but my RhinoCAM only allows me to pull up, move over, then plunge down and not ramp on tabs. My previous experience with Alum was successful, but on the 3rd piece (out of one sheet) - I started to get some vibration as it lifted off the table and consequently was not exact as I hoped. I was using both vac and clamps - but it was not enough to keep the pieces in place. I've explained to the client that I can try to use the tab method - as long as he was willing to pay for $50 bits. Any suggestions - with regards to ramp and tabs?
Tom

[Brady Watson]

Yes. Look into upgrading your PartWorks to the latest version or invest in V-Carve Pro. RhinoCAM lacks specific toolpath strategies and other options made for CNC routing. It is great for lots of things, but if you can't ramp into the cut, it is nearly worthless for aluminum routing.

Don't take this the wrong way but, I wouldn't dream of telling a customer they have to spring for $50 bits because I could not hold something down...That's MY job to figure that stuff out & why he is paying me. I would suggest checking out my "Vacuum Film Technique (http://www.talkshopbot.com/forum/showthread.php?t=11481)" and try using that before going the tabbing route. I'm sure you'd rather avoid cleaning up tabs on AL - and the edge quality will be superior without them.

Try to avoid clamps or screws as they can dink & distort the sheet causing it to bubble up in ways you didn't think it would. It doesn't matter as much what kind of vacuum you have - more so how you use it.

-B

[tomwillis]

Great - thanks for the feedback.
tw

[coryatjohn]

I just finished an aluminum project using 6061-T6 extruded. It was a part to an obsolete automotive door. I used my NextEngine scanner to scan the old broken part (glued back together) then Rhino to fix defects and Aspire to toolpath it. The bit was an Amana 51406 1/8" single flute super-O.

The stock was 1/2 x 3/4. That little bit did a great job. No lube or coolant used. The part fit perfect the first time and the door is back in service.

[donclifton]

John, what was your feed and RPM's on the little 1/8 bit.
Thanks
Don Clifton

[donclifton]

John, how deep of cuts were you taking.
Thanks again
Don

[coryatjohn]

Don -

Pass depth: .025
Feed rate: 1 ips
RPM: 14k

The chips are a little small at these settings but the bit stays room temp. I believe it could take twice the speed but I prefer to go slow and not tempt fate (or physics).

[donclifton]

Thanks John I'll giver a try.
Thanks
Don Clifton

[WoodMarvels.com]

How much is a block of aluminium in your neck of the woods? I've been thinking of designing things out of it just for fun. Is there a special grade needed or any aluminium is fine?

Jon

[RichardG]

Some prototypes we milled out of 3" x 3" x 11" block. Single flute 3/8" at .1" depth for the rough cut, 1/4" ball nose for finish, and some micro end mills for small details. I'm using air for cooling. Its a rather capable machine for aluminum

[WoodMarvels.com]

Very beautiful pictures QDS... how long does it take to cut that?

Jon

[RichardG]

The outside took around 7 hours I believe

[twelchPTM]

i saw these pics when you posted it before, what is it?

[RichardG]

Its a prototype for a product we are working on. I will share more details when it is announced