Foamcutter Rebuild

[OzDragonflyer]

Hi All,

Though I'd share my rebuild, and hopefully give/receive some ideas/opinions/advice.

I made a cutter over 4yrs ago, from mdf. Served well! But time to make something better & more reliable.

I pondered the options for the lower x carriages with the materials available, what I have, and what is cheap! These assemblies are the ones that seem to bind/stall the most, as they have to support the weight of the y carriages and their motors, and the hotwire bow if used.

So, here's what I came up with.. fortunately these will be made using a cnc router, but it might be possible with normal tools with a bit of patience.

Still working on the rebuild of the y uprights, thinking cheap sintered bronze bushings might work because there's not a lot of lateral force on them.

I'll post pics of the rebuild if there's enough interest. Hopefully it will be much smoother and more accurate than the last!

Any other ideas/opinions along the way would be great!

cheers

odf

[slipery]

Have a look at what moreil did at Build a cheap, SIMPLE, CnC foam cutter..
He used linear bearings from vxb which are $US24.95 for a set of 4
http://www.vxb.com/page/bearings/PROD/12mmLinearMotionSystems/LME12UU

and I see that http://www.marchantdice.com in the UK also have similar available.

Cheers MAL

[OzDragonflyer]

Thanks Mal. Mikes machine is nice, but not that 'inexpensive'

The cost of the linear bearings,plus the shafting, really starts to all add up.

The mechanics of this design work out to 1/2 to 1/3 of the cost. The downside is a bit more building/assembly work.

Seems to be a local shortage of the nylon/acetal material I was going to use, and to keep costs down, have gone back to doublesided 16mm laminated mdf. The laminate helps keep the mdf changing size with humidity, and only the edges will need sealing.

All the parts have been cut out, so I'll post some pics soon of putting it together. Looks promising so far!

[BMTECH]

ODF
how is the rebuild going ?

should be cutting a test core tonight



Rick

[planekrazie]

Yea, Just checking to see how the build is coming. Id like to revamp mine now that My router is done.
Steve

[OzDragonflyer]

Haven't been able to access my account on here for a while.

Build is coming along very nicely. I've routed out all the parts, and have constructed one of the horizontal axis' and will spin it up soon. Pics on the weekend.

Also,I was sick of being limited to using a third party interface and separate heat/timer boards. Over the last few weeks I've designed and built a integrated pc interface with pic based timer/heat functions. The great thing about it is that it can be used for both a cnc mill/router and a foamcutter at the flick of a switch.

Here's a mockup of the basic layout. I've tried to keep the centre of gravity low by mounting the y stepper way down, as the uprights on the original cutter used to sway a little when changing direction. The first parts made from this model fit together perfect!

Not sure how the bow will be mounted yet....

[planekrazie]

Did you CNC route your foamcutter. If so Id love to have the files. Looks great.

[BMTECH]

Dave will take some pics of the table & bow, will post later ( your set up is the same as Glenns )


Rick

[BMTECH]

Here are some pics, The bow is supported from the roof with the cord with the bow at an angle to the table ,the wire is dropped into the slot on the y axis which is paper based phonelic ?(spelling ) we can get the x axis's full travel with this set up (note this is not the bow we use as it had no wire in it but you will get the idea) it has to be quit wide so as to not fowl on the y axis.


R

[planekrazie]

Do you get any slop on the Y axis. What I mean does it move back and forth like a tree in the wind? That was my problem on mine. I need to rebuild mine. Here is the pic.

[BMTECH]

Originally Posted by planekrazie Do you get any slop on the Y axis. What I mean does it move back and forth like a tree in the wind? That was my problem on mine. I need to rebuild mine. Here is the pic.

Its not to bad but we are only cutting 30/40mm high with a large bow that damps out some of the movment.

[gguidi]

I just finished my cnc foam cutter. Photos can be found at this linkhttp://www.depronlasercutting.com/foam.html

I am running CeNeCe cutting at about 20

Gary Guidi

Depron Laser Cutting