I keep trying to cut this 1/4 inch aluminum sheet. 4x6’’ and I broke to 1/8 inch spiral bits. Why do they keep breaking and how do I cut it. its a 6064 aluminum I think btw. Please help
also Im trying to cut all the way through.
Are you trying to cut all the way through in one pass? What settings are you using for speed and depth of cut?
The more info you give, the easier it is for folks here to help you out.
Aluminum has to be cut relatively slow and very shallow. Typically you’d use an O-flute up-spiral bit so you get lots of good material ejection and the stuff doesn’t melt and gum up the bit. Use a lower RPM setting on your spindle, and cut passes of about 1/2 mm at a time. You can also use cutting oil (or even tri-flow) applied during cutting to help keep it the bit cool. If it overheats or you push your feed too deep or too fast it’ll break.
You also have to be careful as the cut gets deep - You may want to cut a 3/16" pocket around your part instead of a simple 1/8" outside profile. That will keep the bit from chattering back and forth inside the channel. The chatter can break the bits, or generate excess heat, which can break the bits.
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I agree on the o flute. Also is it necessary that you cut with a 1/8 in bit? If you can use a bigger bit (1/4 or even 3/16) bigger bit is going be stronger and deflect less, run cooler and eject chips more efficiently. If you must use 1/8 in. like Jason said low and slow.
I cut aluminium @ 60ipm/0.004" with a 3mm 3F Helix upcut bit.
Mainly dry with the occasional splash of WD40.
RPM 10k
DIY CNC, not as rigid as xcarve.
This is what I use for all my .25in aluminium, brass, and copper. I use window cleaner here and there to cool parts when using super glue to hold part. Can also hone them with a diamond file for extended life.
On a Carbide3D Nomad (more similar to the Carvey than the X-Carve, I think), I cut aluminum with a 2-flute 1/8" uncoated carbide bit, dry at 0.01" depth of cut at 8 in/min at 9200 RPM.
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