PDA

View Full Version : Need Help! '4' Axis foam cutter?



Plan_B
08-22-2012, 03:45 PM
Hello there,
I've built a couple router machines, and now I'm about to move on to a foam cutter. I have what is probably a 'stupid' question, but that's not unusual for me...

searching on line I've noticed that some machines produce 'tapered' cuts by having all axes independent. The question is: how do you deal with the length of the cutting wire? Once it's on an angle, it needs to either stretch, or be fed somehow?

Thanks!

bopierce
08-23-2012, 12:07 PM
Attached each end of the wire to a spring the attach the spring to your bussbar.

Plan_B
08-23-2012, 12:37 PM
Hi! Thanks for the reply.
I guess to select the right springs, I need to find out what wire gauge and tension is needed. Are there any rules of thumb about that that I can use for a starting point? The wire span is going to be about 5 1/2 ft.

I'd love to see some other people's designs for the wire holding/spring arrangement. Would you or anyone else be willing to share pictures of yours?

I appreciate your help - thanks again!

bopierce
08-24-2012, 11:17 AM
Here are some pics of how we set the wires. this is a production cutter and we use mutiple wires with a 150amp power supply. We use 2 different types of springs, one is 1 1/4" the other is a 4" spring. We also use either a .014 or a .021 dia wire depending on the cut. It might take some playing around to figure out what size of spring that will work.
Hope this helps.

neilw20
08-25-2012, 10:34 AM
Threaded rod is an easy way to line up the wire in nice even steps.
Did it that way 45 years ago. Multiple wires, springs and an adjustable arc welder.

Plan_B
08-25-2012, 11:42 AM
Thanks a lot for the replies.
I'm guessing that with the spring attachment, you can probably get no more than a foot or two of offset between the two ends of the cutter wire? I think you would need some long springs to get much more.

That multi wire machine drawing 150 A, The power supply is somewhere around 50 VDC?

bopierce
08-25-2012, 12:00 PM
The power supply is actually a 150amp Payne engineering scr 240acv input variable output. Voltage depends on wire size.

phil c
02-22-2017, 02:09 PM
Springs are the cheapest. A short air cylinder that can be fed from both ends will work with a regulator to control the pressure and the force on the wire. Unless you are VERY critical on alignment, a simply hook and eye is OK. I used a pulley with the spring running around it and an inch of spring showing to make a more compact setup. Works fine with angle up to 20 degrees or so.