LR V2 and Tall Z height for Foam Cutting only

LowRider CNC Advice
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Hey guys, I’ve been lurking and learning all I can and I think that it’s finally time to pull the trigger and start planning my LR v2 build, been watching the threads of the beta builds and wanted to see if you think I’m setting myself up for a huge failure here. The reason that I’ve always wanted a full sheet CNC machine was to machine high-density foam to be used as bucks for making car body panels.

The video from the shop that inspired this all did his blanks with a full sheet CNC that had a cut area of 5’ x 10’ x 6" and from the videos, I can see a very long, very thin drill bit/bull nose end mill. Again, my goal is only to cut the kind of foam you’d get at a Home Depot or Lowes that is dense. I would love a 10" Z height - but worried about setting myself up for failure going so high.

Thanks for all of the inspiration - watching your builds has me itching to get started.
Also, anyone else milling foam on the bots?

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6" sounds very reasonable with the lowrider, 10" proably in foam maybe not all in 1 pass. If you recessed the table to compensate for such a long bit it shouldn’t be too bad.

Can you really buy a bit that long?

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I’ve built a couple of foam core fiberglass aircraft (1:1 Scale). Always used a hot wire cutter. I was thinking of trying something like this.

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Yes, FrogTools offer a foam bit that 10" long. Wouldn’t attempt a single pass unless it was a very small hole for alignment of panels.
Will also try the one that Barry linked to as well. Good to know that I’m on the right track. The other concern is going to be dust collection and a boot that will go around a long bit. Might have to make a side collector that pushes the foam dust towards the wall.

Ultimately - great to hear that a 6 - 10" Z height won’t be a show stopper. Thanks all.
Link to the FrogTools bits: http://www.3dcutting.com/solutions/frogtools.html

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Was looking at this and the possibility of doing a hot wire cutter that would do all of the rough cutting of the Y-axis. These kinds of hot knives are typically used on Styrofoam - I was planning on using this material to make my bucks.

So, not sure if that will work for me. But worth a shot! Thanks for that link.

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The nice thing about the LR is that you can easily make it a 3/4" machine by just not raising it that much. I’m not sure how long my Z pipes and thread are, but I would guess I have 8" or so if I went all the way up, but it’s super rigid at 3/4", and the extra isn’t doing anything.

So yeah, on the MPCNC, the advice is to start small, learn CAM and then grow if you want to live dangerously, and by then you don’t need forum advice. With the LR, you can CAM small, and then go big, and then if it’s not rigid enough, just shrink again :). It doesn’t require cutting anything.

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EPS (Expanded PolyStyrene) is what they make ‘Styrofoam’ out of (insulated coffee cups, and the like). It is made from pellets that are ‘expanded’ to fill a mold.

XPS (eXtruded PolyStyrene) is is the material you linked to (rigid insulation). It is the same base material, just made by a different process.

Here’s info on hot-wire-cutting: http://gallery.hotwirefoamfactory.com/faqs/faqs-foam/ good luck with your project, however you choose to proceed.

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Awesome, thanks for those links and that info! Once I have things going will be looking into a way to add a wire to the Y-axis that I can cut the rough shape out with, to save on time and help cut down on time needed to do pssses with the spindle.