[henny496]

Hello
Has anyone machined aluminum with a router? I have to put on an Ogee edge onto some 3/4 in 6061 My mill is not hooked up yet(550 motor) so I have bolted a bracket to the mill table to hold the router
I can use the X Y Z axis on the mill
any advice before I start?
Tom

[powerrodsmike]

It would seem to me that a router is too fast, and doesn't have the spindle bearings that will hold up at all. Are you using a router bit designed for wood?

If you do it, get ready for some smoke, HOT chips, loaded up router bits and noise. Maybe you can make several passes, with a super slow feed rate, use a bunch of coolant.

I know I've hit my steel table a few times with a router, doing woodwork, and it doesn't take long for the bit to self destruct.

I have used regular single cut burrs on aluminum with my 22000 rpm die grinders, but you don't get much material removal per pass, and you need some type of lube. Wax stick works ok, and there are sprays that you can use on the bit to keep them from loading up.


HTH, Mikey

[Jake_Dragon]

Wear eye protection

[Arrowhead]

Yea, it works, sorta. I made a bunch of parts from 1/2" aluminum headlight mounts, mirror mounts, exhaust hangers, windshield posts. I cut the rough shape with a cirtcular saw and then smoothed it out with a router. Belt sander works pretty good too.

I used a carbide 1/2" bit. it would chew through quite a bit, but it was slow and the aluminum did get hot. Watch out when the bit breaks, it will go flying. I blew up two routers and about 4 bits.

Check out entry #20
http://www.hotrodders.com/forum/jour...age=5&reverse=

[61bone]

I'd wear more than eye protection. If you figure it out, the pieces that start flying when the bit breaks are going to traveling almost as fast as a 30-30 bullet if you use a standard wood router. A kevlar vest would be nice.

[Henry Highrise]

I just would not do it....way too hazardous...when the bit desenegrates you could get hit and hurt badly. A fragment to the jugular vein and you would be gone before they could get a ambulance there.

[oldred]

Don't try it, that thing will be turning much too fast and the other guys are right you could get seriously hurt doing that. I saw a bit disintegrate after accidentally hitting a steel bar and it is amazing how far the pieces flew and how hard they hit. It MIGHT work if you use a router speed reducer to slow down the bit and then take light slow cuts until you get where you are going but I think the router is going to lack the power necessary and the spindle bearing will probably fail before you get very far.

[OneMoreTime]

H"mmm? ..Does anyone have a clue as to the proper bit speeds for cutting or machining aluminum..?? I would like to try it for some small parts..

Sam

[Henry Highrise]

In the Navy they always taught us to never use a tool for something that it was not designed for. There was a good reason for that.....Safety.

[OneMoreTime]

http://www.woodweb.com/knowledge_bas...NC_Router.html This is a discussion of machining aluminum..If I were to use a router I woudl use my production router with the 1/2" collet as the spindles and bearings in that puppy are a lot more robust than the small 1/4" collets..use lots of wd40 as a spray and clamp the alloy very tightly to avoid any chatter..Having a lexan chip shield mounted to the machine to deflect the chips away from the operator would be a neccessity..Also mounting the router in some kind of fixture like a mill would be good..

H'mmm looked up an answer to my own question..
Sam

[speedydeedy]

Just hook up your mill and do it right and safely.

[powerrodsmike]

Originally Posted by OneMoreTime

H"mmm? ..Does anyone have a clue as to the proper bit speeds for cutting or machining aluminum..?? I would like to try it for some small parts..

Sam

My Sharp milling machine has a maximum speed of 4500 rpm.

I am not a schooled machinist, and I can't cipher how much change I am supposed to get from the taco lady at lunch time, but here is what I found....

In my copy of Machinery's Handbook, 15th edition, it gives cutting speeds in "surface feet per minute". The maximum of 15000 sfm is given for aluminum, when using carbide cutters and coolant.

That is 15000 sfm divided by the circumference of the tool= RPM.

Using that formula, with a 1/2 diameter bit I get 19000 rpm.

It also shows a feed per revolution of .003" per tooth at a cut depth of 1/16" or less. ( I personally think that is a bit fast )

Operating at these high speeds is dependant on the rigidity of the machine, spindle and clamps. I am sure that use of a cutter designed for aluminum is assumed as well. It does have a big asterisk next to the entry for aluminum that says "use coolant".

A router bit designed for wood will most likely give some poor results at that speed...and like the other folks have said, will probably wind up embedded in your walls and body.

Later, mikey

[Dugg]

Mikey is bang-on.

Additionally, router bits are not designed with chip breaking/clearance back cuts. Routers are designed for wood. Look what happens with a router encounters a knot. It's a friendly trade of sorts, an exchange of speed and heat that burns the wood and dulls the router bit.

When I buy steel or aluminum tubing, bar or plate, there aren't any fu**ing knots in it.

Hers'e where I'd refer you to the Machinist's Handbook, but don't bother. The concept of using a router is flawed. Spare yourself the a**-ache.

The aircraft industry uses routers, but they are really very large, high speed horizontal and vertical milling machines and while they may not be using coolant, your router can't use it and it wouldn't work without it.

[powerrodsmike]

Did I do the math right?

I think I messed up with the calculations, the circumference of the tool should probably be converted to feet, instead of inches.

(told ya I can't do math good)

Also,

There are other SFM values for different types of tool materials. HSS was not listed, and cemented carbide has a SFM rating while end milling aluminum of about 1275 sfm.

Using that as a max cutting speed, it wins up being vastly slower than 19000 rpm.

Later, mikey

[fiscus]

Aluminum you can pretty much machine at whatever speed you want as long as it is safe and within the machine's capabilities.