New to all this.....I have some questions.

[ajinjax]

The owner of the company recently decided that we needed a foam CNC mill and a foam hot wire cutter. We had EZCNC build us one that has both the mill and hot wire on one machine.





We were using DeskCNC to write the G-code but have since bought BobCad-cam which as far as I can tell works 1000% better.

DeskCNC was only writing G1 movement and the machine was bouncing around like a car driving on a washboard road when it made arcs on the Z.

I did some test cutting air with BobCam and things look much better.

We're a bit stalled right now because the original laptop that had DeskCNC on it, along with the machine settings, was stolen.


Anyways I have a few questions about the hotwire side.

1. Are there typical feeds for certain types of foam? (We're using EPS 1.5#)
2. How long is a wire's, INCONEL, life span? (I hear they wear out.)


Any help would be great fully appreciated.

TIA

[Cutting foam]

Ajinjax,

we needed a foam CNC mill and a foam hot wire cutter.

Never seen that idea on a commercial machine before, it must be a complete original. What do you do that requires a 2 in 1 solution?

"Feed rates/wire speed" are related to the wire temp and foam density. On new blocks we often do a quick test to see if we need to change any setting. We have found differences in suppliers with the same density of foam and sometimes in different foam orders. The standard density (1lb I think) will run 800 - 1000mm whereas the high density could be 700 - 850mm. Extruded foam (DOW blue) runs 450 - 550mm. If the wire temp is turned up you can run a lot quicker but you can loose a lot of accuracy on a complex shape, it won't make to much difference for a packaging piece but for a custom mould it could be crucial, we tend to err on the side of accuracy not speed.

On the inconel we haven't found a pattern, sometimes a wire can last months (10 or 11) other times we have broke wires in quick succession, for no obvious reason. Other times it has been operator error: moving the independent axis to far or adjusting wire temp far too high. We try to have a number of spares made up ready to go, but it not a thing that we worry about too much. It's a pain in the **** when one breaks doing a complex cut in a large block, but **** happens, a bit like having your laptop stolen.

[ajinjax]

Thanks at least I have some base line to start with.

We're mainly planing on using the how wire for curved pool gutters.

[ajinjax]

Well the hotwire will be for pool gutters and the mill side we'll be machining parts for 3D fiberglass molds.

[Cartesian-xyz]

Check this out!
http://www.hotwiredirect.com/files/v...rill-Tower.wmv

More applications in the works, such as a Router!
Check it out

[chuggins143]

Total nube here, but I threw together a hotwire setup one afternoon just to see if it would work... had a 120 to 12VAC transformer (elcheapo from local electronics store, I think it put out up to 25A), a simple rectifier to make DC, and a SCR to turn the voltage down. We hooked it up with the SCR turned all the way down which gave me about 5 VDC and ran it through some .035 SS welding wire (hodged podged a bow together... about 3ft of wire between the connections) and it cut standard white styrofoam like butter, no problems at all. Just a thought there on the welding wire... it's cheap, readily available, and comes in several different diameters.
Good luck,
C