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Craig Hogarth
08-20-2007, 4:34 PM
Either 1/8 or 1/4 rowmark. Anyone ever try this? I'm trying to do numbered tent stands for a restaurant.

Brian Robison
08-20-2007, 4:40 PM
Under the description it will say if it's heat bendable.
Do you have a heat strip?

Eric Allen
08-21-2007, 6:45 PM
Seems like I read that this stuff is bendable. Might check with Johnson Plastics, those people have been REALLY helpful when I call. If you feel like destroying a toaster oven, you can make a heat strip. Or they sell for around $150 neighborhood for a 31" if I remember right, less for the smaller. Of course, I never buy less....:D

James Rambo
08-21-2007, 7:25 PM
I found a bending strip on ebay - 48 inch plastic bending strip. A plastic heating strip for up to 1/4 inch acrylic. But I read somewhere that the laser engravable plastic will create small cracks at the bend.

Eric Allen
08-22-2007, 2:53 PM
I found a bending strip on ebay - 48 inch plastic bending strip. A plastic heating strip for up to 1/4 inch acrylic. But I read somewhere that the laser engravable plastic will create small cracks at the bend.

I suppose if the heating strip causes that kind of issue due to uneven stress or something along those lines you could always try heating in a small convection oven on a flat plate. A little trickier to bend, but if it worked....Wish I had some to test, I'm going to go get a little dedicated oven to do that and some powder coating work.

Russ Miller
08-23-2007, 1:55 PM
We bend this material all of the time at TAP Plastics. We use a strip heater like this: http://www.tapplastics.com/shop/product.php?pid=291& Check out the VIDEO linked at the bottom of the page. I've also made my own MINI bending wire by using Nichrome Wire and an old Model Train Transformer.:D

Eric Allen
08-23-2007, 5:52 PM
We bend this material all of the time at TAP Plastics. We use a strip heater like this: http://www.tapplastics.com/shop/product.php?pid=291& Check out the VIDEO linked at the bottom of the page. I've also made my own MINI bending wire by using Nichrome Wire and an old Model Train Transformer.:D

I've never stopped in that site, really like the video tutorials on that kind of stuff. We have suppliers close by, might have to check you guys out:) Where do you find nichrome wire, I'm going to have to try that one:)

Russ Miller
08-23-2007, 7:17 PM
It is sometimes hard to find Nichrome Wire listed as such. You can often find it listed as Spring Wire. When the wire gets RED Hot, it expands quite a bit. The way I got around it was to use SPRINGS attached to each end of the wire to hold it under tension. As the wire expanded the springs would compress. I attached the wires from the transformer to the Spring Wire with Alligator Clips.
Be aware that this method only HEATS a very Narrow Strip of the plastic so is only suitable for thin material. Also, make sure that the plastic does not come in contact with the wire. The plastic must rest above the wire about an 1/8" or so.

Stephen Beckham
08-23-2007, 9:31 PM
Craig,

I missed this thread the other day and had I read it, it might have helped me today.

I made a dozen tent stands out of plastic. I'm not sure if you figured out a way yet (didn't go through the whole thread) but what I did was etch the front with text - then flip it over and ran three passes of a 8PT line in raster mode down the center for a bend line. It heated up a thin strip of plastic and removed a bit for squeezing room. I quickly took out the piece and easily folded it in half - held it for a couple seconds (burnt my fingers checking for cooling) :eek: (a couple times more) :mad:.

Since I didn't do anything to the colored surface (Blue on white Romark) there were ugly stretch marks on top in the bend. No issues, because I like to scratch the edges with a knife blade to get a white outline on my plastic anyway. So I used the same knife and swiped the top a couple times.

I can post a picture tomorrow if you'd like...

Steve

Bob Cole
08-24-2007, 12:47 AM
I purchased a 12" line bender from Delvies and it works ok. Think it was $85. Taking it apart, you realize how simple the device is, but hey, didn't want to put one together myself and burn down the shop.

I am by no means an expert, but been experimenting and found that thicker plastic 1/8 compared to 1/16 is much easier to get a good bend. My bender doesn't get as hot at the edges, so I have to place the piece in the center for about 30 seconds, then flip, wait 30 seconds then try to bend (on the heat). Once it is ready to bend easily, take off heat and shape.

If anyone knows of a good forming device like a brake for sheet metal, let me know. The only ones I can find are fairly large (4ft wide) and are really made for sheet metal. The small ones I found were not configurable enough to get a consistent size product.

I have a possible order of 150 name plates that will require bending 1/8" acrylic. I am engraving on colored cast acrylic. If I can't find a forming device, then guess I will get good and bending by eye.

Mike Null
08-24-2007, 7:58 AM
How much will you be charging for the name plates?

Stephen Beckham
08-24-2007, 12:53 PM
Here's the little tents I made. Started out with 3" wide and 4" tall.

Did the text upside down and right side up in one pass.

Flipped the piece over and put the wide strip in the center - while still hot, folded to the angle I wanted.

Now it's about 2" tall and 3" wide. They are really sturdy - the only way to change the angle now is to snap the joint :mad: (BTDT).

Craig Hogarth
08-25-2007, 1:23 AM
I ended up doing what Bob Cole did and just went acrylic.

Stephen, what manufacturer and brand of plastic did you use?

Stephen Beckham
08-26-2007, 5:17 PM
It was a piece of Romark I had laying around. Not sure what I originally bought it for, but it makes "tents" just fine...

Bob Cole
08-27-2007, 12:26 AM
I'm new and pricing this out is a challenge. I did the math and to cover reasonable expenses would need to charge between 15-18 dollars. They take about 5 minutes to engrave/cut (one at a time - haven't run multiples yet to see if there is much time savings), then about 3 minutes to bend (by hand).

I have another style that hooks into the slots on a cubicle that doesn't require as much acrylic (2.5x12inches). The freestanding is 4X10 inches. I was thinking about charging 15 for the cube attachment and 18 for the freestanding.

Adam Stacey
08-28-2007, 9:25 AM
Depending on how sharp a bend you need, you can use a curling iron to sub for a heat strip.