acrylic bender

[Chris Achtschin]

Hi fellow engravers,
I'm looking for the best way to make these "tent" signs for restaurant tables.
They are made of Rowmark material, 1/16" thick.
I've seen some bending machines online that may be the best way to do this.
I have quite a few of these to make so I want to make them the best way I can.
Any suggestions?
Thanks,
Chris

[Jerome Stanek]

When we make those we makes a jig that after you heat them you place them on the jig till they cool. All we do is make one with the correct angles and glue 2 strips of sintra that is the proper width on a board. We have a strip heater that we put a stop so the strip heats the center. also have a timer to keep all of them the same.

[John Blazy]

Great idea of using a timer, Jerome - never thought of that when I use my bender for acrylic. I bought simple 30" and 48" heating elements from McMaster Carr, added wire and a cord to the ends and made a carriage / table to hold the acrylic above the heating element, and the heat from the element rises perfectly straight up onto the acrylic at the bend line. Those heating elements are pretty cheap - a 30" element is only 32 bucks, but you have to wire it. McMaster Carr # 3540K33 in case you want to get one. They have shorter ones for less cost.

[Chris Achtschin]

Has anyone used one of these?
I saw a YouTube video, I think its made in China.

[Joe Pelonio]

Tap Plastics sells the heaters too, but for Rowmark I simply clamp them onto a table edge with a strip of wood with the edge cut to the right angle just on the far side of the center, use a heat gun to soften, and bend by hand. It takes only 10 seconds for it to set. I have made hundreds of them that way, also with 3mm PVC board such as Sintra for vinyl lettering tent signs.

[Kev Williams]

I do all my bending- acrylic and thinner aluminum- using my tool machines...

I engrave a .050"-ish wide kerf on the back side on the bend line, depth about 1/3" the thickness of the substrate.

For plastics, I straddle the kerf with a couple of scrap pieces of trophy aluminum or whatever's handy to act as a heat sink, so that pretty much only the engraved kerf will get hot. A few passes with a heat gun along the line and it'll bend easily. And the bend is always dead to rights perfect.

This makes bending aluminum a piece o' cake.

this is a 3-1/2" x 6" piece of .031" aluminum, the kerfs are about .010" deep, it's ready to be made into a 'shade hood'...
DSC04768.jpg

These edges bend easy-
DSC04770.jpg

But, those corners go away, so a few more bends and they broke off- then I bent the sides
DSC04771.JPG

DSC04774.JPG

it took like 15 seconds to lose the corners (normally I shear them off) and bend the sides. The kerf engraving takes about 40 seconds, part on, cut, part off...

Of course the kerf weakens the material slightly, but for it's purpose, and likewise for a tent-sign bent this way, it's still plenty strong.

For tent signs, you can also cut the kerf with a table saw, best with a 1/16" wide blade. Might take a minute or two to get the depth right...


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[Chris Achtschin]

Thanks all!

[Mike Null]

Kev

Nice tip!!!