[eloid]

hello looking for some creative idea for a low speed spindle to cut Aluminum
anyone know of slow speed motor/ router that suit this... that can be moded
to use end mill bits need to cut Aluminum 1/4 to 3/4 plates.

pls post you pic os solution if you have them

thanks

[Regnar]

Why do you want to slow down the spindle? Most are trying to speed it up for aluminum. Any HSS endmill 2 or 3 flute will work as long as you stay close to the chip load. I have a 4,000 rpm spindle and I wish I could get it up to 20,000. I would be able to move through the material that much quicker. If you are use to working with wood just think of aluminum as a really hard wood. Now if you want to do steel that is when you need to slow the spindle way down and it is pretty much a completely different beast.

Biggest problems Diy'ers face when trying to cut aluminum is the machines rigidity and feeds and speeds. If your machine is shaking all over the bit is to so it wears it out quicker and applys more stress to the bit. If your machine cannot match the feed speed of the spindle it will warm up the bit and instead of burning it will well aluminum in the flutes and pretty much stop cutting until they are removed. Both will cause issues.

You can go with a vfd and spindle the this will allow you to slow down and still maintain torque. You will want to reach the "Chinesse Spindle" Thread in this forum for more information. Eitherway good luck with your adventure

Here is an example of a router cutting aluminum. [ame="http://www.youtube.com/watch?v=MLTAeE6j4_s&feature=related"]YouTube - My home-made CNC router milling some aluminium[/ame]

[electronicwood]

I've just started experimenting with cutting aluminum, mostly because I want to use my machine to make some simple aluminum parts to upgrade it. The way I see the problem (if I'm reading the Machinery's Handbook correctly) there are two issues. First, you need to keep the tip speed of the cutter in the correct range. Second, you need to take the proper depth of cut per each pass of the cutter edge.

It seems to me that the issue with my machine is getting the cutter tip speed low enough and the feed rate high enough. I have a very basic Porter-Cable fixed-speed router that spins at 22k rpm. If I put a 1/2" bit in it, the tip speed is over the recommended value. If I use a 1/4" or 1/8" bit this value falls into the correct range. Also, because of the very high rpm level, I can only take a very small amount of material per pass of the cutting edge. My very first experiments with a 1/2" diameter carbide cutter at 30 ipm feed gave very good results for facing the material in the x-y plane, but miserable results cutting in the x-z plane. In both cases I was taking a cut of about 0.015" deep by about 0.3" wide. I never had any issues with aluminum building up on the cutter.

I was going to experiment with slowing the router down with one of those speed reducers that go in line with the power cord. Do you have any specific advice about improving the cut quality? Would it help to take lighter cuts at higher feed rates?

[ger21]

Buy router bits designed for cutting aluminum at router speeds. www.onsrud.com

[Regnar]

When you say miserable results what is exactly happening? Are you ramping in or plunging. If your plunging is it a center cutting endmill. Any reason why you want to use a 1/2" endmill over the 1/4" endmill?

[eloid]

I have some very hard / tougher grade aluminum plate im working with... not
sure the grade but its not light weigh and it much harder than standard machine grade aluminum ( project 1). The second reason I want to slow down the speed is im plan on cutting stainless steel plate 1/8- 3-16 thick, I require 45 bevel chamfer on the profile , Im looking to make these coating plates for friend in efs stucco bussiness

if your interested here a youtube video of stucco coating machine using the profile plate im talking about.

[ame="http://www.youtube.com/watch?v=gBDUvs3HWWA&feature=related"]YouTube - Easy-Coat Silver Architectural Foam Coating Machine[/ame]

you can see the profile plate im talking about near the end when
the coating is applied to the foam.....

[ger21]

Not sure what you're machine looks like, but it's extremely unlikely you'll be cutting SS plate on a router, regardless of the spindle.

[eloid]

i will not be cutting i will be grinding the bevels, the cutting will be done via lasser cutter from 3d party... i only need to have a jig / template and grind
the bevels in via diamond wheels and bits...

[arizonavideo]

A standard 500 watt "chopper" light dimmer will let you slow down your router.

It will also reduce your low speed torque so you will only be able to go about 60% of top speed and still have enough power left to do the cut.

I used this setup for a little bit until I got my Hitachi M12VC. This made a world of difference with the true fixed speed control. For AL and and a 1/4 single flute cutter 15K was cutting just fine. I have yet to try the larger cutters.