Lets share some tool paths - 3d aluminium machining

In the UK sheet ali is rife with low grades. I find the only way to mill it is slower speeds and tons of coolant. I was working on some 6mm 30 grade yesterday and had to turn the air jets off. Soon as it warmed up it gummed up.

My local machine shop recommends fast speeds which I tired. They also sold me a special cutter. Initially I had good success at 24000 rpm then the note changed. Almost like the bit was going dull…

@Vince.Fab I’m relatively confident I’ve got my machine trammed well, but I will go over it and try and get it better again.
What DOC do you think is possible on a contour cut? Again I’ve only done cuts at lower rpm so will test again with higher rpm this time - it was around the 0.5mm region which now seems pitiful haha. I feel that getting air into the channel to evacuate the chips is very key on contour cuts.

@Luke
Australia has been similar for me, lots of 5083 and worse around. Though I’ve just found a place that will do sheet 6061, not sure if they can do bar stock.

That was my experience with it too, no matter what I tried, eventually I got small amounts of Aly welded to the cutter, and it started sounding like a dull cutter, then it would stop cutting and start loading up the machine… I was lucky not to bend the machine or rip a carriage off. This new stuff is miles better, and by the sounds I can push a lot harder still :slight_smile:

Much better chips today on the contour path :smile:

1mm doc
1200mm/min feed
24k rpm
0.35mm finishing path ( awesome tip thank you @Vince.Fab, this resulted in an infinitely better finish)


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@stutaylo Bigger chips and better finishes at the same time, that’s what i’m talking about! Good job, pretty healthy doc and feed too. How did it sound? How hot were the chips coming off?

Wall finish looks great!

Hard to estimate the temperature of the chips, but they were warm when hitting my hand about 6" from the cutter, not hot enough to burn me though.

It was definitely noisy during the cut, but not horrible.The sound was good when the channel was clear of chips, but as I don’t have an air blast in there, it got a bit noisy when hitting already cut chips. , and obviously very quiet when doing the finish pass. Next job is to tram the machine again - Next purchase is an air compressor and flexible nozzle…

I have just ordered some chamfer mills, and am looking at making a metal base for the machine, running on MDF and using wd40 as lubricant is not a long term option. I’m thinking 1/2" steel plate, with T-slot bolted to it, and threaded 1/2" aluminium strips between the T-slot,sized to the cutting area, then trammed flat.

Thanks for the tips, it totally changed the outcome!

Do you guys use the chamfer toolpath in F360 to get good chamfers? I have heard of people using the trace toolpath with an offset.

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Sorry about the video quality and short post, but I’ve been sitting on this for a while.
As discussed above, I made a 3-axis probe that is tool diameter independent (with limitations). I still need to add a screw for attaching a clip, and I probably will need to hold it while probing. Here’s a video of the first test.
@Luke @Griff @patofoto

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Boom, and just like that I’m interested.

Your macro skills are wonderful! I’m tempted to mill a probe from stock. Technically could that hole be anywhere on the probe?

@neilferreri
That’s ingenious! What I love most about it is that, if the bit is symmetric, it won’t matter how the bit is oriented during the probing cycle.

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That is awesome, do you have a macro to use the plate upside down to only probe the z height? Say for a tool change or if using non-square stock?

I’ll just cut the end off of a ‘learning experience’ endmill to use for the probing

Hey @neilferreri. I have been away for a long time and come home to discover your new probe and macro. Sooooo excited. Not sure if my Nomad would be a good Idea to mill my probe. Have a model that I designed a long time ago when we started chatting about this. Will plan some paths and see how long it will take. Haven’t checked all this post. Is this macro somewhere?.

Not quite, it’d have to be bi-laterally symmetric along X & Y. Most end mills are radially symmetrical. it’s still pretty cool, though.

@stutaylo CNCjs has a built-in Z-probe, and, sure, you’d be able to flip it over for that.

@patofoto Here: Lets share some tool paths - 3d aluminium machining

@Luke Sorry for hijacking the thread again, I’ll start a new one when I have a minute.

@Griff I really want to try your test part, but after the last one I realized that an enclosure (or something) needs to happen first.
Why don’t we use a vac with aluminum? I think I read that somewhere…

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Thats ok… I will soon be rolling out a new production run of probes in line with this macro :smiley:

Nice to have some fresh thinking… about 6 months back I thought the shapeoko probe did this… auto tool width detection… turns out it was just a fluke. Having this out there - super cool!

Will this macro work for UGS users? Hole probing would be very very useful

Just CNCJS I believe…

@neilferreri I’m flattered…but don’t bother, it is needlessly complicated. But, twas a good learning experience. Every day I learn how much I don’t know about cad cam. And Blender. And VCarve pro. And Scluptris. And Inkscape. And Slicer PE…

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I’ve kinda wondered the same thing, albeit I have vacuumed aluminum for a single project, like a year ago…and the stuff is still embedded inside all of my hoses? Obvious thing comes to mind if you’re using any sort of lube it’ll make a mess of your dust collection equipment, other thing is if the lube is in anyway flammable stray static could cause…kaboom! Now sawdust in the air by itself can be pretty splosive too, pretty much anything that can burn given enough surface area to create a good fuel/air mixture will flash. I’m sure there’s other reasons too.

Dan

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The vacuum is spread over a larger area than you can direct an air stream…it just plain doesn’t work as well.

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That makes perfect sense. But could you possibly do a combo blow+vacuum?

Dan

Lets take it a step further. Why not reroute the vacuum exhaust to blow chips, it’s already doing the work!

Sure you couldn’t neck it down but it would still work pretty well, plus you’re recycling :joy:

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I like this approach. I know I’m not the first to think about it, but with a sealed enclosure air blowing from the front of the spindle, and then exhausted to the rear of the machine you’d only need to either push or pull air in one side right? No dust boot needed. You’d have to get the airflow right so you wouldn’t be blowing chips into your machine, but in theory it could work.

Dan