hello
I need to cut in a dibond plate (aluminum + composite) with a 0.3mm aluminum layer on each side.
I have a 1 teeth 1/8 bit special aluminum.
Is there any information on milling aluminum with the MPCNC somewhere?
Can you give me the first indications for those who tried with the MPCNC: depth of cut and feed rate?
I found plenty of information on milling aluminum but would like to hear from those who tried on the MPCNC?
Thank’s
The aluminum on dibond is probably gonna be something gummier than the usual 6000 series that gets cut on CNCs.
I’ve recently cutout some pieces out of 0.5mm thick 1000 series aluminum, and I’ve found out that it’s thin enough that you can easily cut it in a full dept pass without using an adaptive toolpath.
However, it gums up tools much faster than usual. To avoid it, on a single flute, I was going at 700mm/min.
You are gonna have to figure it out, because different grades machine differently, if I were you I would do at least two passes: one to cut the top aluminum layer and part of the polyethylene, and another for the rest.
However, I’ve never machined PE, and it may require different feed rates. In that case, just do a 0,3mm DOC with aluminum speeds, then dial in your feeds for the plastic layer, and finish with another 0.3 pass.
Also, there is an aluminum guide: https://www.v1engineering.com/aluminum-guide/
Go to https://www.cnccookbook.com/10-tips-for-cnc-router-aluminum-cutting-success/ It’s a great resource for cnc stuff and it’s got a section or videos for milling aluminum.
https://www.youtube.com/watch?v=xEdkyE1cV5g is on a mpcnc. USE the collequel cutting option in ESTLCAM
I misspelled the word but it’s a cut that only cuts 40% and the bit goes in circles to remove aluminum. Use a single flute aluminum bit. With the collequel cutting it overlaps and it takes longer but has much less stress on the bit and spindles
thank you for your comments I will read all this carefully
I would avoid trochoidal for dibond. I was able to cut it on my mpcnc in one pass for 3mm dibond, 14 mm/s and the 660 turned down, later the 611 turned pretty far down. Single flute cutter. You gotta go pretty fast for a lot of plastics.
Taking off the first layer, then doing the core works too, but takes a lot of extra programming, but the aluminum layers are thin enough to go a little faster.
Thank’s I made my first cut today with 10mm/s 17000rpm in 2 pass and it was like butter.
actually, I think it goes well in 1 pass, and even a little faster. I will test your settings next time.
You probably aren’t dumb enough to make the mistake I did, but don’t ever plunge an end-mill straight into aluminum. Do a helical plunge, or if possible use lead-ins starting at a spot off the material.
That was the word! Trochoidal - Why not? Everything I’ve read indicates it’s better - and takes longer, to use for aluminum. This is a learning moment for me so don’t take it wrong. I was going to use it to do the same thing in a couple of weeks. I really need to know why not. Thanks, Aaron,
Mike
Because Dibond is a sandwich of .3mm aluminum, 2.4mm (for 3mm dibond) of plastic, and another .3mm of aluminum. Once you break through the .3mm of aluminum, there is soft plastic.
Trochoidal has 2 main advantages: it lets you cut hard materials and gives a good amount of room for chips to clear, and it let’s you cut deep, engaging more of the tool.
Dibond isn’t that hard because the aluminum is very thin, and plastic is fairly soft. The most common thicknesses of dibond actually quite thin for use with signage. So theres no real advantage to using trochoidal for this material, when standard cutting strategies work just fine.
I never knew that existed. That makes sense as the Tri cutting would gum up the flute blade with the plastic by doing that. I’m going to have to look into that material for some things I’m making. Is it really expensive? Thanks for clearing the mystery up for me. Mike
Trochodial works for some plastics, acrylic for example if you don’t have a single flute end mill. Like Aaron said, it makes a larger cut to get the chips out. My first successful cuts were with trochodial. It can help us out because our cnc isn’t as stiff as others, so it gives some leeway with your cam. You should be able to cut dibond pretty much the same way you’d cut hdpe or pvc. The aluminum is almost a foil, so it’s not really going to cause any issues.
Yep. Trochoidal will work fine, but it will just take longer. Why do that when you can machine it with standard toolpath strategies? it’s similar to cutting copper clad pcb’s, but even easier since you’re probably not doing anything small so you don’t need tiny fragile endmills, and the support material is way softer than what they use in pcb’s. Dibond, HDU, Expanded PVC, Gatorfoam, all were developed to be cut really easily by CNC machines.
[attachment file=103273]
this is for those who do not know what the dibond is.
And yes it cuts very easily with a good 1 flute 1/8 bit; in 1 pass without trochoidal.
A lot of us have probably seen it and didn’t know what it was. It’s used in buildings all the time. If you’ve ever seen wall panels at an airport that looks like metal, it’s most likely dibond.
That’s really cool. Never knew that was available. Thanks
