Make a CNC Hot Wire Foam Cutter from parts available at your local hardware store

Picture of Make a CNC Hot Wire Foam Cutter from parts available at your local hardware store
Make a CNC Hot Wire Foam Cutter from parts available at your local hardware store like HomeDepot . This machine can be used to cut wings for RC planes, surfboards, crown molding, packaging foam and lots more

The original design was built in order to cut RC wings (even tapered wings - where one side is different then the other side)

Polystyrene (EPS and XPS) will cut using a hot wire - other foams - like polyurethane should only be cut with a blade or saw.

When cutting, be careful !!! - wire will get hot, and some people may be allergic to the EPS fumes - always work in a well ventilated area.

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Step 1: Over View

Picture of Over View
Most parts can be found in your local hardware store, like Home Depot..
The first prototype was made out of wood, but didn't look "professional" enough, so I decided to go with a more robust design made of steel.

The design can be modified to almost any size. Keep in mind that for longer travel you will need a longer lead screw.
The problem with a long lead screw is that because it its own mass, it will "wobble" in higher speeds.
One way to overcome this problem is to move to a larger diameter lead screw.
Another way is to move to a chain or belt driven design. Belt driven machines are usually 8' and longer but require the use of micro-stepping. An example of a machine larger then 8 foot would be a surfboard foam cutter.
Some surfboards are up to 12 feet in length, the only way to cut these boards would be a belt driven or chain driven mechanism
I will try to cover this topic in the future with a sample machine and pictures...

We started out building a machine to cut wing cores, but soon after we discovered a huge interest in the machine for other industries - like moldings, architectures, surfboards, Logos, props, packaging Willow Sills, Casings, Wainscoat , Fascia, Crown, Parapets, Wallcaps, Pediments, Quatrefoils, Columns

is there anyone to help by details of dimensions that i sholud use for the above model or else the ratios .?

Andy S.4 years ago
Is there any one willing to build this CNC Cutter for me I am in northern California willing to travel any were in California looking to cut 4X8 blocks of foam to make crown molding, Thanks
I would love to build this project for you while building one for myself. I live in Los Angeles. 818 two o9 four 967
tbarnea (author)  Andy S.4 years ago
Hi there
We are in northen CA -

madmark710 months ago
Taking into account that the instructable says parts available at the local store . Did you use regular threded rod and nuts from home depot as the leaded screw ?
Thank you
tbarnea (author)  madmark710 months ago
Yes - thats correct
you can always go the a larger diameter threaded rod and nut to get higher speeds
madmark710 months ago
I could not find the exact part by the numbers and there is some 4x6 and some 4x4 half bases at home depot can you specify which is the one ?
interesting design. Very clean. one question though: What gauge/size wire did you finalize the design with? My instinct is to go with heavy gauge to minimize/eliminate breakage but will I lose resolution?
Kinnishian1 year ago
In the instructables, you mentioned "click here for more information" about the abrasive wire type of cutters. There is no hyper link, though. Do you have any suggestions for more info about abrasive wire cutters?
ACME threads are much better then UTS threads when the threads will be used for moving parts, not just permanent or semi-permanent assembly. ACME threads are more wear-resistant and contamination-tolerant than their UTS counterparts. The reason UTS is good is that they don't migrate out of their holes as much; ACME threaded screws need to be re-tightened far more frequently.
idk about ACME , if they make the screws the same quality as their rockets i'll pass
ACME isn't even a company. Or at least its not one particular company; there are many companies that call themselves Acme [fill in the blank]. Just look at  this wikipedia page.
*facepalm* joke post taken too seriously D=
haven't you ever seen the roadrunner and coyote cartoons?
I know, but a lot of people actually do think that there is some ACME giganticonglomeracorp somewhere.
Kinnishian1 year ago
Does anyone have tips for breaking wire? I put together a simple foam cutter for making precise width rectangular prisms, but I find the wire breaks even at a slow pace after several runs. I'm thinking perhaps the problem is that I am using Constantan wire, which is some blend of copper and nickel, in similar proportions to how Nichrome is nickel and chrome. I'll try it out with nichrome, but in theory I think Constantan should have similar high temperature strength.

This is a wonderful instructable! I hope the company gets some sales, the machines you guys have looks great.
lordduckx2 years ago
Thats fantastic!

About how much did this all cost? I'm really interested in replicating it
I'm curious about that myself.
ultratuga3 years ago
Amazing. One friend of mine is doing all this mannualy. This will be may gift to him. Thanks .
Credito Pessoal
trebuchet035 years ago
Is there such a beast as a 3 axis hot wire CNC? Can I index the bed and spin 90 degrees? For perspective... I want to make something akin to the photo below - well, a mold for it anyway... I would think, depending on design, I wouldn't be able to cut everything, but it would cut down on hand sanding time :) And I imagine I'd need a belt drive due to the long length... Or maybe I need to make a hot stick CNC and remove material that way....
I run the 3D Prototyping Lab at NIAR. We have a Z406 printer. I highly discourage this technology for anything that needs tolerances or is used for fit of function.
hi! I was just thingking is there a 3d printer that could produce an aluminum output or any type of metal? things would much esier and more faster in the field of manufacturing and engineering...just thingking how will this things be made, since designs are abundant...and just can't wait when will this things be made or even see how will this machine works.^_^. 
Direct Metal Laser Sintering is a process that uses a powdered form of a metal, i.e. titanium, chromium cobalt, aluminum, stainless steel, and builds the part layer by layer by sintering the powder together with a laser.  I've priced out an EOS Direct Metal Laser Sintering (DMLS) last year.  It costs around $540,000 and an extra $20K for the titanium setup. 
Other companies make them, but they are still tremendously expensive.  My wife and I were considering purchasing some RP equipment in support of my product development company.
3d printer that uses tin/antimony solder instead of plastic might be a interesting idea.
Thanks!..i just saw the video from youtube it was really quick it is from design to its actual prototype....just cant keep on wondering how much faster will it be in the coming future...
Instead of direct metal sintering, maybe a 3d printer that uses a soldering iron as heat source and tin/antimony solder instead of plastic?
I don't even see the Z406 on their site anymore. We have been working with Zcorp on a new product manufacturing application and have had no problems with their newer machines. Perhaps your issue has been resolved in newer models.
Rapid proto can be done any # of ways. ZCorp printers are great for color prints, desktop models, form concepts, surface verification (we've done some models from video games, etc. ZCorp Printers are bad for Fit and Function prints due to their anisotropic scaling that results from the powder prints. From my industry contacts, the newer machines have improved the "processing" of the parts, but the accuracy of the tolerances and the quality of finer detail is still an issue. I print a lot of aerospace prototypes with very fine edges, etc. The 310 has a smaller print capacity than ours though it is more automated. If I had it my way, I would have both a ZCorp and a FDM or a SLA machine. What organization do you work for?
(removed by author or community request)
omnibot Llewner5 years ago
How about a fab@home or a RepRap. They're based on making usable parts.
I guess it's hard to see the scale from that picture - that thing is about 8+ feet long (that one is not the one I was involved in, but is a great example of the compound curves involved) :p I've used a zcorp machine for printing parts - but, here's an FDM I made a few months ago for this past year's project (second picture is of the model in a water tunnel). Oh, this is a fairing for a human powered vehicle ;) The last picture shows the stacked cross section method...
Nifty! Actually, my comment was a bit of a joke. I used to build kayak's and know that foam stacking process all too well. ;) But just imagine if there WAS such a thing as a 12' zcorp! ;) Minimal sanding and insta-mold!
How about the model boat makers techinque, draw a set of slices, sandwich them, then sandpaper them into a curve.
Edgar Edgar5 years ago
Wait, complex curves can be made, to a point... Just make the 2 points were the wire sticks from, move in angle to each other, i.e. one higher, one lower, then leveled, the to the other side. How? Hummm... Get some 3D wizz to do a program!
Edgar Edgar5 years ago
...Or see this:
Foam cutter
Check this out

So that's the current method I'm using - but I'd like to save time and potentially some money by making it from a single block of foam - with a decent degree of accuracy :)
You could probably make it work with this setup if you added a 3rd axis to rotate the block of foam. Of course, you could only reliably make convex or axially-symmetric shapes.
tbarnea (author)  trebuchet035 years ago
This would look like a 3D CNC router job
cut four foam circles for this
Savinous Wind Turbine.jpg1980.jpg
I see your plane parts and they look smooth . I have idea cut circles for savanious wind turbines. making four circles three or four feet in diameter should be no problem. next rout a couple flat bottomed s shapes into the discs use adhesives gorilla glue ,silicone to adhere the pieces together. My first HAWT was plywood and aluminum flanged pipe cut in half the foam is lighter and after assembly could be coated with polymers or powder coated with some coating to make it a uv resistant and possibly after further rounding over or stream lining. I hope adventually some one will do this challenge project. the cnc plasma could easly cut steel parts to support the foam at each disc attach it to the shafting fabricate bearing supports ect

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