Not rigid enough? working with 6061 Aluminum

Hi all,
Got the new enclosed desk top Carvey, and doing test passes on a sheet of 6061 1/4 thick aluminum. Feed and depth are very slow and shallow (.030/in min, .0005 per pass), 1/8 3 flute endmill. The cut chatters badly and you can see the spindle bend under the torque. I’ve set the endmil so the flutes come right up to the collet.

So what am I missing? This machine doesn’t seem rigid enough.

For aluminum on Carvey to get the best results you’ll want:

  1. A coated bit designed for aluminum. There isn’t a good way to add lubrication while it’s running so coated bits help with that.

  2. Helical or torchoidal toolpaths like they have in Fusion 360. This gives constant bit engagement.

  3. Graduated plunging or ramping like they have in Fusion 360

If aluminum is your main work material, you’re going to be putting some serious time in. The machine is capable if it’s your option.
As @Zach_Kaplan said, it’s all about the toolpaths.
Here are some pics and video of a recent Aluminum/Carvey job.
I ran this with a .125" spiral, single flute bit.
Feed 250mm/min.
Depth per pass was an experimental 3.5mm with an optimal load of 0.127mm. Generated in Fusion 360.
I ended up stopping every once in a while to remove chips and, eventually, add some WD-40.

Hi Bill, yea its .005 :wink: yea I was hoping to use this for small aluminum jobs.

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Fusion360 and a better tool bit seem to be my next test options for this little machine.
Thanks.

Even with a super shallow DOC, you may run into areas of your first pass that are not flat and end up plowing through more material than you want. I have Fusion 360 face 0.2mm of “air” above my stock. I put “air” in quotes because it always cuts some aluminum.

Just trowing it in, denatured alcohol is much less messy than WD40 - there is no oily residue left behind.
It also evaporate providing a cooling effect.

I machine a bit of alu (on a different machine) and with a 3mm 1F bit (about 1/8") I can do 450mm/min , 3mm DoC and 1,2mm WoC at 18k rpm or so (chip thickness 0.025mm)
Toolpath is Fusion360 / 2D adaptive
Rigidity is the main factor for material removal rate (MRR)

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Thanks for the tip.
I was improvising when I got uncomfortable watching the dry milling. I’ll have to get some for next time.

I know the Carvey can’t handle that feedrate or width of cut.

I did the same, and used WD40 myself. Now I use a mister and it mixes in denatured alcohol. Simple mister off eBay.

I dont know so I´ll take your numbers any day :wink:
I was just giving context to the tool path strategy offered from F360 vs the “Easel” way :slight_smile:

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Slower does not mean better. It’s about cutting edge engagement and material removal rates.

The toolpaths in fusion put less force in the machine and have higher bit engagement.

I’ve emailed them for help on a tutorial.

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Hi Bill, new cutter in the mail. That and some F360 to see if I can get better performance from it. But yea this is a very lightweight machine. I’m already considering others :slight_smile:

I am confused. I am considering purchasing a carvey and using it to cut a 4"x6"x1" block of aluminum to make aluminum molds. Can it do it? The spindle sounds weak at only 300 watts? I will make sure to get a coated bit. I did understand that proper paths are needed.

What’s the difference between a CNC mill and a X-carve/Carvey? Aren’t they CNC mills? (Sorry for the dumb question)

What is this guy? Is this a mill or router?
https://www.youtube.com/watch?v=ku-PPP0mTxo

I need to do about 20 molds but the rest of the time I would like to carve wood. Can the carvey handle cutting 20 aluminum blocks?

I like the Carvey as its less messy and easier to use for someone who knows nothing about CNC. I have friends that want to make signs and carved wood designs throughout the year. I do wish Carvey had a slightly bigger work area but I like everything self contained like a printer. But maybe I am asking for too much?

More for use inside an office/home. I don’t like to be in the shop when I am running repeated jobs.

My impression is that this machine won’t work for my mold use (the main reason to buy it). The other reason to become a hobbyist and learn more about the art but that’s only worth $500 to me.

Can the carvey make a wood plaque like this but smaller?

I read that not all CNC machines can do 3D carving. Most do 2.5D

Aluminium molds => you need a very rigid rig to pull this off. ANY slack/give/backlash will show up as reduced surface quality as metals are very intolerant to this.

So the bottom line is, if you require “mirror” surface a hobby machine will not be plug’n’play/ready for the tast.
If surface quality dont require a mirror finish then a hobby machine may be warranted. But that wont be plug’n’play either, you still need to know the machine and dial it in.

A CNC mill is a fixed spindle (in X/Y) , where the bed move in the X/Y direction. Since the bed is moving the X/Y range is less. But accuracy/rigidity is very good. Usually big and heavy.
A CNC router have a moving spindle and fixed bed. Cost less for a larger cut area, lower accurancy and/or speed.

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Is their a software difference between x-carve and carvey?

I ordered this one - the Tormach 440. It paid for itself in two months time. I keep the x-carve (heavily modified), because the work envelope on the Tormach is only 6" x 10". I do stainless steel on the Tormach too!

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