CNC Hotwire 4 axis foam cutter

[Skipsoaring]

After some computer issues, I can get going on the learning side of things again.
I found Autodesk Fusion 360 (thanks again to the info here) which integrates CAD and CAM so have started using it. I'm brand new to Macs so am still learning the in's and out's of screen shots etc.
I won't be having the foam cutter anything other than flat as it wouldn't be possible to keep the foam block and the cut part in the correct position at the end of the cuts and would cause damage to the parts. With the block flat, I can use double-sided tape and gravity.

Better keep drawing, hopefully have some info and pics for you soon.
Clayt

[Boyan Silyavski]

Show us what exactly will be the final part. If its a 3d shape you will need a router, not wire cutter.

[njhussey]

Show us what exactly will be the final part. If its a 3d shape you will need a router, not wire cutter.

Boyan, if it's for cutting RC plane foam wing cores then a hot wire cutter (4 axis) is the thing to go for. I'll be making one at some stage (10 years time at my current build rate! !!) For exactly the same use.

[Skipsoaring]

Show us what exactly will be the final part. If its a 3d shape you will need a router, not wire cutter.

Normally cutting wing cores from foam requires passing a hot wire over 2 fences shaped with the aerofoil at either end of the foam block. CNC will provide the same service and remove timing errors and snags (getting stuck) giving a much more accurate wing core.

[mitchejc]

Sorry can't help you with any info on the 4 axis hot wire but Silyavski may have a point depending on what you want to do. If you need to cut a lot of wing profiles rapidly the hot wire is obviously the way to go but if time is on your side then simple 3 axis milling is not such a bad idea as it gives you a lot of options that hot wire can't do. A relatively flimsy but fast 3 axis router dedicated to foam cutting should be easy to build.

Had to dig around to find the model but several years back I did cut a few gliders for a friend on my router. He asked me to cut two wing profiles and I suggested we cut the whole aircraft in one go. The entire model including the fuselage was cut from one big piece of foam with a two sided strategy excluding the wing tips which were glued on afterwards. The screenshots below shows the model I drew using his wing profile. I know sh%t about aerodynamics so I just went with a sort of a teardrop shaped thing for the fuselage so he's got somewhere to put the battery and receiver:-) The white round bits you see on the wings are just supports used when I turned it over to cut the bottom profile. The piece of foam was bigger than the model so it was supported at the wingtips as well.



Don't think I have any pics of the actual cut models but apparently they flew very nicely :-)

[Skipsoaring]

Nice work on the glider Mitchejc. I agree that a router would be much more versatile and I will be making one to go along with the hotwire. One of the crucial things with supplying wing cores for people to finish is to also supply the beds. A router cuts the beds into little bits that are really hard to put back together ;-)
I'm aiming to produce 3 types of glider from foam as kits and hopefully the funds from them will help me to make my 'aluminium capable' router for making parts and moulds for composite gliders.
Prototypes for the composite gliders will be routed as you suggested above, especially the fuselages.

[Skipsoaring]

I've built both if you call and eshapeoko strong enough to cut ali ..so if you do need any advice pleased to give it..and I just live down the road in Chestow.. Ok its the M4 ..I've programmed my own arduino based hotwire controller which is compatible with mach3 and GMFC, which I'd be glad to share and I've tried quite a lot of the software out there such as Mach3, and most of the devcad stuff including profili

Thanks mate, I'd be glad to get some help, especially with the program bits.
Clayt.

[Skipsoaring]

Thanks for that. Some rene on its way. Power supply is going to take some thought. It will need to be adjustable as the foam types and sizes will differ regularly.
Design of the machine is coming along slowly (the drawing is the slow bit, the design is evolving in my head)