Idea: The Flyplotter

[Balu]

I've looked into CNC machines for a few days and I'm really amazed what people build these days.

If you just want to draw, perhaps something like this might work too: https://www.youtube.com/watch?v=euMkoUePxog

Also DIY machines like the Phlatbot can be modified to work with just a pen:
https://www.youtube.com/watch?v=Nj701D6zrNI

 

[Tritium]

I have a ShapeOko that I am currently retrofitting to a larger size bed and a 4 motor drive rather than 3 as shipped. The new size will be a cutting area of roughly 1 X 2 meters. I also have obtained an 808nM 2000mW TTL gated laser module from Kale CNC that I am mounting to it for cutting. I do not know its cutting capabilities yet as far as material types. They do cut poster board and paper well at 1000mW power level so I am hopeful that it will do foamboard without any issues. After retrofit I hope to use pen, laser, dremel or plasma cutter as the tool of choice depending on material being cut.

Thurmond

 

[Balu]

Nice. Version 1 or 2 of the ShapeOko?

Instead of getting a laser I'd try to use a "knife attachment" like "Donek Tools Drag Knife" to avoid problems with undercut. I've seen similar DIY holders.

With 2 W you might have to work at quite low speeds. The resulting heat will not be good for the foam.

I'd be interested to see how it works though.

 

[JasonEricAnderson]

Forgot to post my latest doodle.

 

[rcspaceflight]

Looks simple enough. Two rollers powered by one motor to move the sheet of foam. Another motor to move the pen back and forth. Is that a servo to trigger the "pen" to release ink? So just three components working together. Nice.

 

[JasonEricAnderson]

Is that a servo to trigger the "pen" to release ink?

Yup. The servo would just lever the pen up enough to pull it off the paper while it travels to the next point it would need to start a line.

 

[rcspaceflight]

I couldn't sleep and I was thinking about this project of yours. I was thinking how you could skip a step and it dawned on me. What if you replaced the pen with a soldering iron with the tip replaced with a finishing nail? I couldn't find a finishing nail so I tried it using a paper clip instead. I gotta say, it cuts through the foam extremely well. The paper not so well. But it does work. You'd have to slow the machine down, but you could skip the step of having to cut it out by hand and just let the machine do it for you.

I may have to attempt to build one too (with the hot wire cutting method instead of a pen). I find flying more enjoyable than building.

 

[EraJomppa]

This but make it bigger

 

[rcspaceflight]

This but make it bigger

But then how do you make sure to keep the scale correct?

I really want to branch off of Jason's idea and make a "Hot Wire Printer" that can cut out foam board. I was thinking of using servos to power it, but probably servos hacked into continuous servos. Just to keep cost down since I actually want it to move rather slowly. I don't need powerful motors, I just need to gear them down a lot. I really need to look into how to program it so I can just take a CAD file or .png or whatever and just hit a "print" button.

 

[EraJomppa]

But then how do you make sure to keep the scale correct?

Really just a fun simple Idea to try out

But! You could adjust the arm lengths (keeping the angles correct I think) and trying different versions until the machine's reach equals to the size of DTFB for example. The instructions say 4", go with 10" etc.

 

[Balu]

Just giving some more input for ideas:

http://www.instructables.com/id/PrintO-Bot/

 

[TheFrogman123]

would love to see it, if the blade doesn't work out, you could use a dremel and do it that way.

 

[JasonEricAnderson]

would love to see it, if the blade doesn't work out, you could use a dremel and do it that way.

There are lots of dremel based CNC machines and those would work great for this. The Shapeoko is my favorite and I'd love to get one. Part of what I want to do is keep the system to as few moving parts as possible.

I'm going to try and and build a working prototype over the winter and I'll be braindumping here as I go. Who knows, if I can get this working I might get a kickstarter going so that people can get kits to build one themselves.

 

[xuzme720]

Oh man! That would be awesome! I'd love to be able to afford a CNC router/dremel...

 

[willsonman]

Great to see you back on this idea.

 

[SnowRocker88]

I don't know if you moved away from it yet but I think a tractor system to move the foam board is the least attractive method. If you were moving a rigid board and had variable lengths or fed from a roll or something then it'd be more attractive but it's a fairly easily compressible medium that is always in the same lengths. You can assume that you will always have the same size base so why not just a dual rail system?

I haven't priced them but there's a company named Amacoil that makes "rolling ring linear drives". Basically they're tilted roller bearings that form a spiral path on a shaft. Based on the simplicity of the design they should be fairly cheap. I was thinking of starting an X Y table project myself and my thoughts were based on using one of these per axis (one for the X slide and one for the Y slide) and just using the rail as both the rigid guide/slide and the drive system. The smallest unit won't slip until like 28lbs of force or so which would be WELL beyond what you would see just drawing on foam.

I'll put together a model of what I was thinking and post it up when I get some time. It should be fairly clean and simple yet still fairly rigid and accurate.

 

[JasonEricAnderson]

Awesome!

The tractor idea of the Y axis is just to try and limit how many moving parts (fail points) I would have. Originally I was thinking of having a more CNC table style but then I was thinking of regular inkjet printers and their tractor feeds.

In case anyone is curious here's my current brain dump:
Phase 1

• Get the basics for a tool chain proof of concept
• Arduino (check)
• Motor Shield
• Small recycled stepper motors for testing (check)
• InkScape GCode plugins to write GCode (check) Example workflow
• Arduino GCode interpreter (found maybe?)
• Wire up some tests and see if I can get the steppers to spin as needed based on the gCode

Phase 2

• Build a test platform for the rails
• Build a sled/carriage for the pen
• Get some better steppers
• Build out the mechanical parts - Bearings, sled, rails, belts/Kevlar wire
• Get the contraption to draw some basic shapes with a usable level of accuracy
• Dial in points of improvements and plan next version.
• Start printing out plans directly on sheets!!!

 

[SnowRocker88]

So, here's what I have so far. The bulk of the purchased parts (everything but the frame parts, the Amacoil parts and the shafts) sums up to about $160 before shipping and tax. The rest I'll figure up and update at some point.



I'm thinking this is the most efficient setup as far as number of parts. I think I can come up with something better for the second level slide. Right now my 'anti rotation feature' is a plate with cam followers...which are $20 a pop. I'm thinking I can do a delrin anti-rotation and still keep accuracy. I'll noodle on it and come back.

It's something I've been wanting to start for a while but haven't had a chance to start on. It's a back-burner kind of project for me.

I'm really looking forward to you getting yours together so I'll have something to go off of. I'm a mechanical designer by trade and the electrical stuff is not my strong suit.

 

[SnowRocker88]

The Amacoil drives turned out to be about $150 each. They're not extremely pricey but as I'm going for a super budget build (and since there are already plenty of X Y tables that cost $300-400 to build) I'm going to look into a different route. Probably Delrin ACME nuts or Bronze ACME nuts and ACME threaded rods. Thinking 1/2"-10 but maybe bigger. I want them to be the support as well as the drive.

I'll let you know what I come up with.

 

[paulshort]

Have you heard of GRBL. it reads g code and runs CNC machines with just a arduino uno. I will hopefully soon be building a CNC machine with it.