Help with cutting Aluminum

I made this part in the past out of 1/4 inch aluminum. 6061 and it came out great

Now I’m making a key chain out of 1/8 inch aluminum 6061
I am using same bit sizes feeds and speeds. Only difference is I have a 1/4 ball do a profile cut first to give a nice edge


My problem is that the bit gets filled with aluminum this time. Use plenty of lune and air to clear cutting bit.

Doc is .05 with a 1/8 inch 4 Flute EM feed is 20 Ipm
Using dewalt set on 2. Have stiffing mods.


Here you can see my wood test comes out great but when going to aluminum everything goes wrong lol

I think I found the problem just by writing this lol DOC is to big needs to be .005 not .05 :sob:

I am using a DOC of 0.02" with a single flute 1/8" endmill (not ballnose) and I cut at 45 IPM…dry cut, no lube.

What are you cutting? What is your machine? Mods?

Currently I have the 3/16th steel bar between the Y-Axis makerslides, supports for the X-Axis slides attaching it to the wasteboard, and nylock nuts securing the eccentric nuts (now washers), I used the dewalt on speed 1. I have done a bit more lately, but those settings are what I ran on that setup.

Edit: that was cutting 6061 aluminum T6…1/4" plate

Here is the thread that covers everything I have done to the machine…it is a long read…lol

one thing that helps is to wipe the bit down with 3 in 1 oil between cuts. Chips won’t stick to the bit, even if you’re not using coolant.

Theres a lot of optimizations you need to be aware of when cutting aluminum (at least, on a production scale, which it looks like your gonna ramp up to).

Your feed rate is a bit too low you want to maintain ~.005-.01 inch per tooth (chipload). If not, you will “rub” the tool and you’ll get chip welding (as you’ve experienced). Once you’ve got your feed rate you need to do a little bit of testing to figure out a usable depth of cut that your spindle (and frame/steppers) can handle. IIRC, I used to run 18-20k RPM, 60 in/min @ .015" doc, slotting with a 3flute ZrN coated 1/8" EM.

Your 4flute EM can easily cause the chip welding. Most ‘aluminum-optimized’ EMs are 3flute, and even then I’m having trouble evacuating the chips fast enough. There just isn’t enough space for the chips to clear effectively. I’ve never welded chips with a single flute and with a 2flute I’ve only welded chips when I don’t use air or any lubricant.

1 Like

Single flutes are the only way to go!

Thanks all for the help so far got some 2f 1/8 EM bits any Rec in feed and speeds?

Also a 2f 1/16 ball. I use this for the letters 1/8 for everything else

Have you found a decent place to purchase aluminum from ? I see it at the box home improvement stores too

My place of work is right next to a metal yard so ya I get pretty good price

I would say, speed on 1, 40 inches per minute minimum and .005 for depth with 2 flute. Then try .01 for depth. I really prefer the two flute bit over three or one for my aluminum and brass milling and also use ZrN coated bits. I use constant air cooling with no lube. I have can of WD40 handy but try not to use it because of the mess.

1 Like

The 2f bits are working great 40 ipm at .005

2 Likes

If you are looking for thick stock I get mine from ebay. I can not even touch a piece like this around here for this price. bought it a few weeks back for a upcoming project.

2 Likes

midwest Indiana I love it here but the only thing near me is corn and meth. The closest place is a hour trip and $50 for the same thing.

3 Likes

The nice part of my last job as a jail officer I knew all the meth heads and they stayed clear of my placeThe slum lord that owns most of the homes down the block lost all of his renters because I moved here lol he hates me. there are only 3 occupied homes down a 2 block stretch of road now. :smiley:

1 Like

I Still have ties to the place but I changed jobs last year because of the lack of any pay increase. and being a small town almost every inmate knew me from growing up with me or from some other job or just related to them that in it’s self makes the job even harder.

1 Like

Check your local Fastenal store.

If you are looking for good metal at good prices, check out https://www.midweststeelsupply.com/store/index.php and http://www.howardprecision.com/random-rack. Both have a huge assortment of metals and fair prices. Their products are in top condition and arrive fast. The random rack to Howard’s is a great place to pick up stock for projects from .125" to over 4" thick. We use either or both of these places weekly for production runs and they are both great to work with. Howard’s random rack is a bit cheaper overall and the more you order, the better the shipping comes out. But you will be hard pressed to get the same size stock week to week so setting up production runs on plates of stock is not as easy as ordering a standardized stock size from Midwest and running the same Gcode job after job when you change out plates.

Try to get the same alloy and temper so your feeds and speeds can move from one job to the next without issues. If you try to cut 5082 at the same feeds and such as 6061 T6, you will find issues and start to dislike milling aluminum dry.

It can not be said enough, keep the chips clear on aluminum while you mill. Air blasting will do a fine job if you are able to keep a steady firm air-stream at right angels to your cutter.

1 Like