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Ian Malings
10-23-2005, 7:28 PM
i am about to do a large project involving thousands of cut to template pieces from 0.5mm styrene film. the pieces range in size from 6" x 11" to 18" x 18" the problem is that the styrene blanks are cut form a large roll, and the material has excellent 'memory' and will not lay flat. has anyone used the 'multimat'? can you vector on it? i do not want to result to using two-sided tape, as that will kill my productivity. thx ian www.lasermarkstudios.com

Lee DeRaud
10-23-2005, 7:49 PM
If it really has that much memory, I'd worry that curl in your cut pieces would also be a problem. Will the blanks flatten out if you zap them with a heat gun?

Ian Malings
10-23-2005, 8:10 PM
the cut pieces will also pose a problem.
for some of the patterns, i can strategically place a scrp pc of stainless to weigh it down, but for others, i can't...

ian
www.lasermarkstudios.com

Joe Pelonio
10-23-2005, 8:55 PM
Ian,

Too bad you don't have the newer Epilog with built in vacuum table. I don't either and also have to do that thin stuff frequently. For any big job what I do is to space them a little further than normal apart, especially with cheap material. Then before starting do an outline 1/8" around the pieces to be cut, and cut that out of a piece of 1/8" wood, or acylic.
That is then placed onto the material to hold it flat. Of course, depending on the shape it will curl again once 1/2-3/4 of the piece is cut and it may
"fly" into the path of the laser, so you have to plan for extras. Also, I have a piece of screen (for windows) that I tape over the vent to prevent the finished pieces from flying out the exhaust.

If that doesn't work, sometimes I'll put the material onto a sacraficial piece of plastic or wood (ususally mdf) using a temporary artists spray adhesive or one for fabris like Sulky KK000.

Bruce Volden
10-24-2005, 7:19 AM
Ian, You may also be able to use magnets of varying sizes, take a look a amazing magnets.com. They have a huge selection and are quite affordable.I've bought a lot over the years, some to use as hold downs, some to insert into box lids to help keep them closed. Bruce

Ian Malings
10-24-2005, 8:11 PM
Joe-
i do have a new epilog helix, but the suction is not sufficient to keep the material flat. io tried masking off the open area, but this stuff just wants to curl.

Bruce-
i thought about the magnets- thanks for confirming. i will try that. it is probably the best bet.

no one has used the multimat?

ian
www.lasermarkstudios.com

Pat Kearney
10-24-2005, 9:21 PM
I also have a Helix and "dido", plastics with even a slight curl will not lay flat unless I lay something on the edges

Joe Pelonio
10-25-2005, 8:22 AM
The I don't feel so bad about buying my laser before they added the vaccum table. I cut a fair amount of polytag stencils and find little pieces all over the parking lot when they fly out the exhaust. With that thin styrene, if you use it a lot, buying 4'x8' sheets and laying it flat in a warm room for a few day might help flatten it. Otherwise the easiest thing might me to just put 3-4 pieces of the thin (not foam) double sided tape on the bottom and attach it to a sacrificial piece of mdf. The tape will rub right off after. I've done that when cutting laminate that's warped. I had to stop using one supplier of IPI, all of it that he sent me was warped.

Ian Malings
10-25-2005, 8:33 PM
this material is being supplied to me in a large diameter roll of 4' wide material.
it will be too much work to use 2 sided tape.
i'm going to try the st stl flats as hold downs and hope they work

thx for the thoughts

ian

Joe Pelonio
10-26-2005, 9:54 AM
I had at one time thought about "inventing" a device to hold down the center of the warped engraving laminate. It just has to be out of the way of the head, you might have to pause and move it at times. It's based on the toilet paper roll holders. Spring inside, and rubber bumbers on each end. It would go between the material and the glass door, and move up and down on the spring with the table as it focuses. Probably not a great idea for a large production job like yours though.