Milling Aluminum with a router

Rob Keeble

Member
Messages
12,633
Location
GTA Ontario Canada
If one wanted to mill a piece of aluminum with a router what bit would i use. What HP router should i be using.?

I assume light cuts if so could i free hand a pocket into a piece of aluminum with a Bosch colt hand held router? Note its only a 1/4" collet.
 
if you are only looking to make a recess in the plate alum why not just drill a series of holes rob, then clean up after wards.. i have seen where routers are used on granite so aluminum would be ok if you take real light cuts!!!!
 
Larry i hear ya but i was thinking of the handibot video i saw and just wondering what bit would be used and why could it not be done with a normal router setup and jig. They got me thinking of making some aluminum discs with a circle cutter. If one drills a hole through center to anchor the circle cutter, one could run the router around and cut discs of aluminum.

What bit to use though. ? Do i go to machine supply shop and buy end mills? Dont know if they come in sizes that fit router collet.
 
Another place where I have more experience than I wanted.
The cutter: 2 flute x 1/4" ball end mill.
Lubricant: aluminum cutting fluid.
The router: the slowest machine you can put your hands on. Your Bosch Colt likely is 16,00 to 35,000 rpm? Would not go there! Rather be at 10,00 or less.
Depth of cut: ~.02- to .030 per pass.
Feed: slow.
Path: fixed in some way. It must be repeatable fro each pass at successive depths.
Length of cutter: only what is needed with the cutter fully engaged in the collet. Too much length guarantees the cutter will snap under load.

How do I know this? I had a lot of help from Onsrud. Now this is assuming you are making a plunge cut, not a trim cut. I was milling a curved slot thru 1/4" thick 6061 (mild) aluminum. Yes, there are different compositions of aluminum. Some nearly impossible to mill. 6061 is best with woodworking tools.
Length of the slot was 5.25 inches. The ball end made the plunge cut much easier on the machine.

The difference between end mills and spiral router bits is that end mills are available in many more collet sizes than router bits. A 1/4" end mil is pretty much the same thing as a 1/4" router bit. End mills also have a plethora of lengths that router bits do not.

Also, there are few tricks to doing this, so if you are really serious in pursuing this, let me know and I will walk you through it bit by bit.

Doable? Yes. Just a few caveats to to master.
 
Rob,

All of what Carol said. We have used routers, for cutting signs letters and designs of both hand held and CNC controlled, on aluminum, with mostly milling cutters of the carbide types for many years. It works well, but just be very cautious.

One thing that I didn't see mentioned is to be careful of the HOT chips the bit will produce. I always wear a long sleeve shirt, a full face shield and a pair of light leather gloves, such as TIG welding gloves. The chips are not only going to be hot, but also very sharp. You don't need to be worrying about all the hurts while trying to hold onto your router safely.

Same thing goes for cutting aluminum on a table saw.

Aloha, Tony
 
Late on this thread, but would your aluminum project lend itself to a carbide tipped blade on a TS rather than a router? I've used my TS a number of times to cut aluminum. Go easy & it works well.
 
Top