Cutting Readi-board foamboard with a CNC router

donektools

Junior Member
I'm not an RC builder, but I got a call from one yesterday. He wanted to know if the Donek Tools Drag Knife could be used to cut Dollar Tree foamboard. I picked up some foamboard today and made a couple test cuts. Check out the results.
 

CrashRecovery

I'm a care bear...Really?
Mentor
Sean,
welcome to the forums! From the distance you are from the camera it looks spot on! Are you looking to offer a cutting service? Also can the cutter be designed to score the paper and not go all the way through it. We score it usually for hinges. Once scored we fold it back and make a 45* cut so it can move. Can the cutter do that or is it simply a vertical cut?
 

FlyingMonkey

Bought Another Trailer
Staff member
Admin
I share Crash's sentiment, welcome to the forum. I'm looking forward to more posts about what you guys are able to cut. It's a service that I think would be highly in demand by folks on here.
 

donektools

Junior Member
Sean,
welcome to the forums! From the distance you are from the camera it looks spot on! Are you looking to offer a cutting service? Also can the cutter be designed to score the paper and not go all the way through it. We score it usually for hinges. Once scored we fold it back and make a 45* cut so it can move. Can the cutter do that or is it simply a vertical cut?

Actually we manufacture the drag knife tool that is doing the cutting. It can be used in any CNC router on the market. While I doubt that would be a service we could offer, I'm sure there are some guys here with CNC routers that could offer such a service using our tool.

I build my 4 year old a double size copy of a paper airplane out of the foamboard this morning. I made a couple teaks to the coding for foamboard and all the corners cut perfectly now. I even cut some tabs to insert into cutouts for aligning parts. I think it's a viable solution to cutting foamboard on a CNC router.

You can find more details on the tool at www.donektools.com
 

CrashRecovery

I'm a care bear...Really?
Mentor
How much does that tip cost? I wonder if my fab shop at the guard base has one? I could cut out every design I want to build in no time. I would have a ceiling full of planes that need electronics
 

earthsciteach

Moderator
Moderator
Looks like you have a really nice product for this application. I'm interested to see how the creasing tool performs, as well. Now, if only I had a CNC machine! Man, I could do some cool stuff!
 

donektools

Junior Member
How much does that tip cost? I wonder if my fab shop at the guard base has one? I could cut out every design I want to build in no time. I would have a ceiling full of planes that need electronics

The drag knife is $229. It uses inexpensive utility blades that cost between $0.15 and $0.30 per cutting surface. We have shipped one to the US army. I'm sure you could show it around and get them to order one.
 

donektools

Junior Member
If you can point me to a design that would use the creaser and can be cut from the 20X30 sheets of foam, I'll cut one. Alternatively, I'd be will to cut one design as a test piece if there is a designer builder willing to put it together in a timely manner and post photos and thoughts on the results.

Preferably in the Denver area.
 

Tritium

Amateur Extra Class K5TWM
Great product but it looks like the price is set according to larger CNC machine pricing structure and certainly not for a hobbyist CNC machine like my ShapeOko which only cost 2X what you are asking for the attachment (wouldn't fit my dremel chuck either I don't think). I need a very light duty low cost model 1/8" shaft for NON-Production environments and revenue streams that could use a utility knife blade and perhaps a #11 X-acto.

Thurmond
 

donektools

Junior Member
Great product but it looks like the price is set according to larger CNC machine pricing structure and certainly not for a hobbyist CNC machine like my ShapeOko which only cost 2X what you are asking for the attachment (wouldn't fit my dremel chuck either I don't think). I need a very light duty low cost model 1/8" shaft for NON-Production environments and revenue streams that could use a utility knife blade and perhaps a #11 X-acto.

Thurmond

Wow. I had no idea there were CNCs that didn't go up to a 1/4in collet. I don't think an 1/8in shaft could handle the stresses applied in this situation. The forces applied at the tip of the blade are substantial.

I checked out your machine. With a DW660 installed you can use a 1/4in tool. That upgrade costs less than $100. Too bad that's not a variable speed tool. 30,000 rpm is too fast for just about anything. You'd need a speed controller on that tool to be really useful with bigger bits.
 
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Tritium

Amateur Extra Class K5TWM
Yea, it is a small affordable machine to "train" one in the application. Mine has been modified and can be configured for as large as 2 meters by 1 meter for the table. It should be very possible to remove the dremel completely and bolt on an adapter to mount a knife with a freely rotatable blade. Although I cannot justify the cost or direct application of your part for my meager machine you have given me ideas about mods for it. I do have a Sears RotoZip that greatly resembles the DW660 that I will look into using as well. Is your knife free rotating or is the spindle indexing it? Thanks much.

Thurmond
 
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donektools

Junior Member
Yea, it is a small affordable machine to "train" one in the application. Mine has been modified and can be configured for as large as 2 meters by 1 meter for the table. It should be very possible to remove the dremel completely and bolt on an adapter to mount a knife with a freely rotatable blade. Although I cannot justify the cost or direct application of your part for my meager machine you have given me ideas about mods for it. I do have a Sears RotoZip that greatly resembles the DW660 that I will look into using as well. Is your knife free rotating or is the spindle indexing it? Thanks much.

Thurmond

The tool has bearings in it. There is a great deal to the execution of a knife like this. It's a simple concept, but a lot has to come together just right for it to function well.
 

Tritium

Amateur Extra Class K5TWM
Thanks Sean, I have nothing but time and a low cost machine. You have given me a new direction to try with it. I think I have an X-Acto knife handle somewhere with a swivel head I can "play" with. It seems like the forces needed for cutting 1/4 "foamboard or bluecore foam / depron would be significantly less than some materials. I will see what I can do.

Thurmond
 

donektools

Junior Member
Sean I posted your link over at the ShapeOko Forum 22 June 2013 and at least 1 guy so far is talking about ordering one, Discussion here:

http://www.shapeoko.com/forum/viewtopic.php?f=24&t=405&start=20

Thurmond

Thanks a lot. I've been thinking of getting a small CNC for my kids to learn on. I was initially thinking about a shopbot desktop, but I'm considering one they can help build and then improve as they get older. I've looked a bit at this shapeoko as well as the www.cncmogul.com. I don't think either machine would pass in a commercial environment, but would be something that they could learn about electronics and making stuff with. How long have you had your machine?
 

Tritium

Amateur Extra Class K5TWM
Since the first production run last year. Most likely nearly a year now. My problem is finding space to use it since I increased it from the stock size. I also have the desire to learn it but not much time so I have not done much with it (I am a Rancher by trade now, retired from Semiconductor Fabrication Equipment Engineering and Maintenance, Telecommunications and IT). Cutting foamboard would be a perfect use for mine so I could get some youth in this area into low cost RC Models very quickly. It is a great introduction into building something mechanical, Arduino and the assembly of the Stepper motor shield then testing and setup with a computer via a usb connection. A lot of technical area is covered in the build as you can see.

My other interest for the ShapeOKO is routing of PCB's for my electronics hobbies.

Thurmond
 

gsaflightsquadron

Junior Member
well i just bought one .its not just the actual tool, its the software the support and honestly its the geomtry of it. ya its half the price i paid for my cnc mach used but its cheaper the a 9k laser machine and does a better job theres no other way to cut dollartree foamboard with the paper on,yes you can use a laser cutter but notice the valley when it burns threw the paper it melts the foam back,this tool dosent have this problem, and the other people making something like it cant cut anything this thick. and its 3 times the price. easy to cut fan fold foam with a tile rotozip bit. but its wavy flimsy and cost more then dollar tree foamboard we use dollartree foamboard b/c it has the paper on it .its a surpior product i make rc airplane kits so i make them in large amounts, cutting them by hand is not a option. yes up front it seems like alot. but ive seen routerbits that cost more.