Vienna now has a(nother?) MPCNC

[stylesuxx]

I finished my build a couple of days ago. I printed the parts over a year ago. Electronics and Hardware also have been lying around for some time. A couple of weeks ago I finally started assembly, everything was working out great. I decided to go with the dual endstop version. I printed some custom part for cable management and some cable chains to make it all look neat.

First test with the pen were a blast! It was square from the first time I used it, which really amazed me.

My main application is cutting Carbon Fiber Plates. Since I did not want to attach a vacuum to get rid of the nasty dust, I build a water container to submerge the carbon fiber plates during cutting - works like a charm and it does not even splash as much as I would have expected.

I use a China Spindle - 400W with ER11 collets and a speed controller. I was surprised by how quiet it is, when running full RPM it is maybe as loud as my vacuum cleaner. I can use my CNC without waking my girlfriend up in the middle of the night - I was totally not expecting that.

Last week I found a great carbon dealer in my area and acquired my first carbon fiber plates.

Just for reference, I used the following settings for my first carbon cutting experiments:

Tool Diameter: 2mm
Horizontal Feed: 8mm/s
Vertical Feed: 3mm/s
Speed: Maximum that the spindle will allow ~30.000RPM
Cut Height: 0.5mm

I have the feeling that I can push it some more, but this settings gave me great results, so I thought, I’d share.

I am very excited about having a machine that works so precise and reliable - this gives me totally new opportunities in making stuff.

Let me know what you think or if you have any questions regarding my build.

Thank you again, Ryan.

Chris

[vicious1 (Ryan)]

Welcome to the crew! Thanks for the pictures, and thank you for using a water bath, nasty stuff is easily kept at bay with a little water.

[rgbskills (Zoltan Benko)]

Hey, Thanks for sharing. Looking to build one my self for the same exact reasons only I would also like a changeable head for a laser but that is optional.

Can you give me some details on the spindle? I need it to be silent as well.

Also can you cut 4mm carbon for bigger carbon quad frames?

I know nothing about CNC routing, I only have XP with 3d printing so feel free too give tips and stuff

[stylesuxx]

Sure, thicker carbon is no problem at all - as mentioned above, my cut height is 0.5 mm, when cutting 4mm carbon it would basically need 8 passes to get through it.

This is more or less the spindle kit that I got => https://www.ebay.at/itm/CNC-400W-Spindle-Motor-Mach3-PWM-Speed-Controller-Mount-Power-Supply-for-Engravi/123255694280 except mine came with a set of ER11 collets.

Those are the endmills I use => https://www.ebay.at/itm/2-38mm-VHM-Fraser-Schaftfraser-fur-Kunststoff-MdF-GFK-Alu-CFK/231593287833 I got 2mm and 3mm. The 2mm I use for smaller frames where I use M2 screws and the 3mm endmills for frames that will use M3 hardware.

[thecheat (Evan)]

Can you share details of your water bath/how you’re holding parts down in it?

[stylesuxx]

The containment for the water is made from white furniture board and some aluminium L profiles. The Profiles were cut and screwed into the the furniture board. Then I used silicone to seal the cracks between the L Profiles themselves and the furniture board. I then tested that it is water tight by filling in water and letting it sit around for a couple of days. The carbon itself I screw to an MDF board with some 3D printed mounts and the MDF board is stuck to the furniture board with double sided sticky tape. I then fill in water until the carbon sheet is fully submerged. I also tried to just stick the carbon to the MDF board with sticky tape, it worked but the sticky tape gunked up the endmill in the last pass, so I decided to screw it to the board instead. Also the type of double sided sticky tape you use matters a lot, some will not stick so well under water but the TESA brand works extremely well for me.

After cutting I suck the contaminated water off with a vacuum cleaner.

The MDF board is unfortunately not ideal as it tends to warp after it gets wet. I can cut a sheet of Carbon in one sitting, but if I cut a small thing, and let the wet MDF sit for some days it warps badly and I need to swap it - so this part is not ideal. I have some doka boards coming (It’s a brand of board that is used here for construction work and thus water proof) I hope this is better suited for submerged usage. I was also thinking about experimenting with PE board, but it is rather expensive and I guess it would be cheaper to sacrifice the much cheaper MDF instead, also I am not sure if I can just screw my carbon to that or if I would need a more elaborate way of clamping it down.

I hope you could follow my explanations, I can take some pics on the weekend.

[atomicb0mberman]

Hi, Chris,

Thanks for sharing, the build looks pretty good! I’d also like to build an MPCNC to cut carbon panels, but I was curious if it would be able to do that - until I found your post.

It would be great to discuss your experiences with you and learn more details about your build:

• How big is the working surface and how high did you build the z-axis?
• Can you also make a statement about the accuracy of milling?
• How thick are your carbon plates normally or what is the thickest plate you could successfully mill?

[bprestwo (Brian Prestwood)]

Cutting carbon fiber drone frames is high on my to-do list for my new, first, CNC.

Nice to know it works so well.

For the pricing I’m seeing on carbon fiber sheets it is hard to justify cutting my own low end frame designs.

Do you mind sharing what you paid for that carbon fiber sheet?

[stylesuxx]

It depends. If I order from the US or China, delivery takes weeks, so for me it is convenient to cut my own stuff if I quickly need something.

Prices vary. 150mm x 300mm x 2mm I can get for around EUR 25 locally.