cutting values for starafoam

[stan kern]

I am not having good luck cutting the blue thick starafoam,the pink starafoam and the type used for meat platters in grocery stores called defe**** something (modellers use it).
Anyone have some values-- power --speed --resolution--air assist (press) that they are using .
My stuff cuts fine but blows out the backside

[Dan Hintz]

Do you mean styrofoam?

[Randy Digby]

Also, the industry name for meat trays, poultry trays, etc. is expanded polystyrene foam..which gives you the base product name. It's the same base material as using in model airplanes, et., but with a blowing agent introduced to expand the product. Never tried to cut it...just made millions of pounds of it...in my previous life.

Styrofoam is Dow's tradename for the product. The product is known more by that name...a lot like Clorox vs. bleach.

[stan kern]

yes some words i cannot seem to spell properly ---sorry about that .
I spend about 2 hrs today trying all speeds,all powers and different table surfaces and the laser will cut 1/8 styrofoam perfectly but when it comes to the 1 in pink and 1.5 blue it cuts in about 1/2 then blows out the backside about 1/4 wide.
I think i have to give up,its not a laser friendly material.
The thin stuff was given to me to try called depron like meat trays in the grocery ,it cuts fine .

[Bill Jermyn]

FWIW I cut 3mm Depron foam at 100 speed, 4 power, 500Hz, 4 passes. If I try to do it in fewer passes it just makes a mess. The kerf width is around .05"

[Peter Meacham]

Stan

I have cut styrofoam with my laser, but was not too satisfied with the cut quality.

So, I now use a hotwire cutter. There are tons of them available in craft stores and on line and plenty of plans on the web to make your own cutter if you wish. It does not take much more than a simple wooden frame, a power source and a guitar string or an old electric heater element to make your own cutter.

What shapes are you cutting with the laser - could you do them with a hotwire cutter instead?

Pete

[stan kern]

i was intenting to try and cut model airplane parts out ,but the depron works great but thats it.
Hot wire would be ok but its not programable
Guess the other cnc would do it but then a hold down is demanded or the parts fly around

[Dan Hintz]

Stan,

Although 1.5" of foam is very light from a laser power point of view, the thickness can be a problem when it comes to focusing. Considering the focus of a lens is hourglass shaped, you're going to see a real drop in power that deep into a material, which causes you to really crank up the power, which causes you to..., etc. It's a never-ending cycle of changes.

[Michael Hunter]

Even if you end up using a hot-wire cutter, laser cut templates will make the job really easy.

I asked about a hot-wire cutter at my local model shop (6" thick foam and sheets too big for the laser) - no go!
They have stopped stuff for "making" as their customers only buy ready-made (all from the far east). If modellers have got that lazy, where is the next generation of engineers going to come from?