Cutting foam sheets... with a needle!

dkj4linux

Elite member
I am working on my needle cutter, and I see that the bearing does help to keep the needle strait, so, I will incorporate them, there is quite a bit of room in the tip for the wire, it will be interesting to see this thing run.
--Does anyone have any hints on hanging the needle on the motor bearing?
--Has anyone tried to harden the tip of the needle?
Rit,

Basically what Jason described to form the needle... look back at post #26 on page 2 of this thread for the way I've used to form the needle for attachment to the flywheel bearing. Rather than CA, I've always grooved the bearing slightly with a cutoff wheel... it can be done if careful not the let it spin up and overheat; i.e. you can use a finger in light contact with the bearing, as a brake, while grooving it, to keep it from spinning up to high speed and overheating.

Shur's flywheel is probably better yet... but like Jason I just haven't taken the time to design a flywheel to hold/enclose the bearing yet. Attachment of the needle would be greatly simplified.

There's no real need to harden the needle... music-/piano-wire is high-quality spring steel that wears well in the application and doesn't require a needle-sharp point. Here's a freshly-pointed needle that's done no cutting yet... and this will, in my experience, most likely be the only sharpening it'll ever need.

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-- David
 

Rit

New member
Ok, wrap the wire around a drill bit, makes sense, I used a deep well socket, but will be using a drill bit next time.
I got the thing running and almost balanced, and have to work on the printer adapter, and a cutting table.......a few more days to go.
 

dkj4linux

Elite member
Does anyone know the best set of tools to generate Gcode for a 3D printer?

Not entirely sure what you are asking...

For 3d printed parts, I start with a STL model (downloaded or generated with Onshape/Tinkercad/etc) that is then sliced using Slic3r, or similar, slicing software (Cura, KISSlicer, etc)... output is gcode file, placed on SD card or sent from PC to printer with a sender program (RepertierHost, UGS, etc). I have a Prusa I3 MK2S and am particularly fond of the Prusa edition of Slic3r... gcode files are read from SD card.

-- David
 

Rit

New member
I am looking to Cut model airplanes, From PDF's using Inkscape, as it looks like it can generate Gcode, I have Duet Electronics and might be able to set it for CNC mode.
Thanks.
 

dkj4linux

Elite member
I am looking to Cut model airplanes, From PDF's using Inkscape, as it looks like it can generate Gcode, I have Duet Electronics and might be able to set it for CNC mode.
Thanks.

Not familiar with Duet electronics so can't help there...

However, a general procedure for preparing PDF plans for needle cutting with Arduino/Marlin is quite well documented in Jason's (jhitesma) video, using Inkscape and Estlcam...


Going on memory here (uh-oh...) -- others, including me -- have also used SketchUp/SketchUCAM for sheet layout and Marlin-compatible gcode generation... Inkscape can be used to convert PDF files to DXF for import.

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Before MPCNC, I used SketchUp/Phlatboyz (now SketchUCAM) to generate gcode for a LinuxCNC/EMC2-driven, BuildYourCNC-inspired, machine.

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Finally, Shur (shurakair), back in post #1447 of this thread, shared a Inkscape Gcode template that allows generation of gcode, using the Gcodetools from within Inkscape itself, that uses different layers to control the different type of cuts (through-, score-, etc). I haven't been able to get this to work since I updated my Inkscape to version 0.92 but I'm sure that it can be made to work again, if this is something you want to pursue. I'm sure Shur's probably already got a fix for that... Shur? :)

Ideas? Hope this helps... :eek:

-- David
 
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Rit

New member
I want to work the cutter on a 3d printer, and I need software to generate the code for it, it needs to Z-hop between part cuts.
 

dkj4linux

Elite member
I want to work the cutter on a 3d printer, and I need software to generate the code for it, it needs to Z-hop between part cuts.

I'm confused (not uncommon...), Rit, as to what you're asking for.

A "stock" MPCNC (pretty conventional, hardware-wise) can be either a CNC machine or a 3D printer, depending on how its Marlin firmware is configured... and the same Marlin firmware is commonly used with many, many 3d-printers. Conventional 3-axis CNC machines and 3d printers all have a fully-functional Z-axis and, depending on how the firmware is configured, can be made to "Z-hop" between parts or progress layer-by-layer, as for 3d printing. So, which it does depends on the firmware used, its configuration, and whether the gcode has been "sliced" or generated as simple 2D/2.5D gcode. As explained in my posts above... Slic3r, Kisslicer, Cura, etc generate "sliced" gcode for 3d printing and Inkscape, Estlcam, SketchUp/SketchUCAM, etc can all be used to generate gcode for the CNC stuff; i.e. for needle-cutting a foamboard RC plane.

Can you be more specific about your 3D printer/CNC machine and the firmware it uses? Using a 3d printer as a CNC machine is certainly possible as I've described -- underneath the extruder, heated bed, and temp control stuff... it is a CNC machine after all. I have a Mendel I2 machine (my first 3D printer) that I converted to a laser-engraver... and it uses the same electronics and firmware (though configured differently to accommodate no extruder or heated bed) as it did when used as a 3d printer. It could handle a needle cutter just as easily but it doesn't have anywhere near the X and Y capacity to be useful as a RC plane cutter.

Please provide as much detail as you can about where you are with your machine and how you want to use it, and I/we will do our best to help.

-- David
 

Rit

New member
Never mind, I am the one confused, Gcode give me a headache, I downloaded the trial of Estlcam and follow (jhitesma)'s video's after the Motrin kicks in.

I just figured out how to set up my printer to use -z and work similar to a CNC.
 

Shurakair

Member
Not familiar with Duet electronics so can't help there...
I haven't been able to get this to work since I updated my Inkscape to version 0.92 but I'm sure that it can be made to work again, if this is something you want to pursue. I'm sure Shur's probably already got a fix for that... Shur? :)
David,
I don't know what the problem you are experiencing could be. I don't use that form of gcode generation any more. Having said that, I still have Inkscape, gcodetools and the template. I just converted the FT Simple Cub page 1 without any issues and was able to successfully generate a reasonable looking gcode file.

Shur
 

dkj4linux

Elite member
Hang in there, Rit. We can do this. The big unknowns here are the Duet/firmware combo... and your plans for this machine. But it's all doable and you do have options. Please don't give up.

Questions:

-- Does your 3D printer/CNC exist... or is it yet to be built?

---- Pictures and/or more info would help immensely.

-- Are you looking to do BOTH 3D printing and CNC with the same machine? This would be difficult.

---- Small CNC is pretty easy with common 3D printers - pen, laser, drag-knife. etc... very light loads. Need tool holders.
---- Few 3d printers can physically accommodate larger sheets of foam for RC.
---- MPCNC, because of larger capacity and Marlin's 3D printing "roots", can be used as 3d printer pretty easily just by enabling the extruder,
------ heated bed, and temp control code that's already there. CNC is a snap. There are literally thousands of MPCNCs out there to prove it.
---- Generic CNC firmware has no 3d printer code in it, therefore it is relatively difficult to add that functionality to it.
---- If you have a 3d printer already and have the room, use the 3D printer to build a dedicated foam cutter machine. This thread is
------ full of examples... MPCNC being prime among them IMO.
---- Are you "flexible" with the Duet controller board and firmware? Mega/RAMPS, mini-RAMBO, RAMBO with Marlin are known to work.
------ UNO/CNC shield with GRBL also known to work.

Hardware:

-- If fully functional X, Y, and Z... machine can potentially be used as CNC or 3D printer. No restrictions, outside of physical capacity, speed,
---- accuracy, tooling.

Controller/firmware:

---- Arduino Mega/RAMPS, mini-RAMBO, RAMBO with Marlin firmware can be configured as CNC or 3D printer. No restrictions.
---- Arduino UNO/CNC shield with GRBL firmware can drive MPCNC or common 3D printer hardware for CNC. No restrictions.
---- Duet with ??? firmware... unknown.

CAM (Gcode generation):

---- Slic3r, Kisslicer, Cura, etc generate "sliced" gcode for 3D printer.
---- Inkscape, Estlcam, SketchUp/SketchUCAM, etc can all generate Marlin- or GRBL-compatible gcode for CNC.

-- David
 
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dkj4linux

Elite member
David,
I don't know what the problem you are experiencing could be. I don't use that form of gcode generation any more. Having said that, I still have Inkscape, gcodetools and the template. I just converted the FT Simple Cub page 1 without any issues and was able to successfully generate a reasonable looking gcode file.

Shur

Thanks, Shur. I do little/no needle-cutting of planes nowadays, so really haven't pursued it. I know that the Inkscape developers really threw the community for a loop with the introduction of Inkscape v0.92, where they changed the internal DPI used... it apparently broke a lot of gcode-related plugins. I think most of that has been sorted out by now and/or workarounds have been found... it threw off the orientation points and other stuff IIRC. JTech's laser plugin now comes in 2 flavors as a result... Inkscape v0.92 and Inkscape v0.91 (and earlier). I've had several computers, mostly Chromebooks (my grandkids needed them) and LinuxMint-flavored Lenovo's, I used over the last couple of years and they all now, for some reason, sport Inkscape v0.92. But even now, I sometimes have trouble with getting properly scaled gcode from the laser plugin... if it runs at all. I think it has to do with different templates; i.e. some of the metric ones seem to work okay with the laser plugin and others don't (the plugin crashes)... including yours IIRC. And since I rarely use the Gcodetools, I don't try to use your template very often.

How do you generate your gcode now? What version of Inkscape are your using? Are you still needle-cutting planes?

It's good to hear from you!

-- David
 

Rit

New member
I am now trying to figure out how to generate a gcode file to send to the printer. I am messing with Estlecam.
 

Shurakair

Member
How do you generate your gcode now? What version of Inkscape are your using? Are you still needle-cutting planes?

It's good to hear from you!

-- David
I have 0.92.2 version of Inkscape. It didn't crash when I used my template and gcodetools to generate some gcode. I did not run the resulting file on my CNC though so I can't say if it worked correctly or not.

I have been using ESTLCAM to generate gcode for awhile now (thanks to this thread I believe).

I haven't cut a plane in awhile, but the last one I did was that FT Simple Cub for a friend of mine last year. I'm about to embark on another plane though and I'm up in the air as to how I'm going to cut it. I'm using MPF instead of DTFB.

Shur
 

Michael9865

Elite member
I have 0.92.2 version of Inkscape. It didn't crash when I used my template and gcodetools to generate some gcode. I did not run the resulting file on my CNC though so I can't say if it worked correctly or not.

I have been using ESTLCAM to generate gcode for awhile now (thanks to this thread I believe).

I haven't cut a plane in awhile, but the last one I did was that FT Simple Cub for a friend of mine last year. I'm about to embark on another plane though and I'm up in the air as to how I'm going to cut it. I'm using MPF instead of DTFB.

Shur
Don't forget to account for MPF being thicker than DTF.
 

dkj4linux

Elite member
I have 0.92.2 version of Inkscape. It didn't crash when I used my template and gcodetools to generate some gcode. I did not run the resulting file on my CNC though so I can't say if it worked correctly or not.

amI have been using ESTLCAM to generate gcode for awhile now (thanks to this thread I believe).

I haven't cut a plane in awhile, but the last one I did was that FT Simple Cub for a friend of mine last year. I'm about to embark on another plane though and I'm up in the air as to how I'm going to cut it. I'm using MPF instead of DTFB.

Shur

That's good news, Shur. I probably just need to completely uninstall Inkscape and reinstall then. I'm using the template you shared in post #1447... is that the correct one? Estlcam is a good piece of software and highly recommended over on the MPCNC forum. Christian Knull, Estlcam's author, monitors the goings-on on there and chimes in when necessary. First class service!

-- David
 

Rit

New member
I'm dying to learn to cut foam board, and am quickly learning how ignorant I am on CNC software, the toughest part is figuring out what I do and do not need to learn, software and such.