Line Bender - what sort should I get?

[Michael Hunter]

Had an enquiry which involved bending acrylic. Although the enquiry went away, it got me thinking that a line bender would be a useful thing to have.

Any recommendations as to type/make?

Also, any "must-have" features that I should look for?


I don't want to spend a fortune on this, but a proper bender has got to be better than my normal method using the wife's range cooker and bits of cardboard to control the heat distribution.

Thanks

[Rodne Gold]

CR clarke in blighty have a great range using heating elements , however we built our own using resistance wire . I like wire benders as they ONLY heat the very narrow strip you want to bend and you get a VERY sharp bend. For thicker then 5mm , you need a double sided heater which heats both sides of the bends.
With a wire bender , you need to have a spring loaded tension system as when the wire gets hot , it droops.
We generally use the laser to score the bend line (for easy placement) and we notch the cut where the bend is to be to stop "sideways bulging"

[Frank Corker]

I have one of those that Rodney mentioned, it is a single sided and I would have been happier with a twin, that said, it works a real treat and great bends. The notch is also something I use as it really makes the bend neater. I got mine on Ebay second hand which had been in one of the schools, worth the money if you get one.

[Michael Hunter]

Thanks guys.

Too late to ring Clarkes now, but I suspect that they will be too expensive. I found two on ebay (not clarke's), new buy-it-now - £399 and £599!

I think that I will be making one.

[Scott Shepherd]

Just a FYI.....

http://www.tapplastics.com/product/supplies_tools/plastic_tools_supplies/plastic_bending_strip_heater_element/169

There is a video clip showing how to make it in the text under the photo.

[Joe Hillmann]

If you want a really cheap way to build one you could straighten out an electric stove top burner, once you get it kind of straight put one end in a vice and the other end in vice grips and pull on it as hard as you can well you have someone else pounding on the vice grips. Once you feel it relax it will be perfectly straight, don't try pulling any more after that or it will break. To power it hook one end up to hot and the other end to a light bulb socket then the other end of the socket to neutral and plug it in. If I remember correctly about a 25 watt bulb will be enough resistance to get the element to just barley begin to glow red which is a good heat for bending acrylic. If you need it hotter put in a lower watt bulb or no bulb at all, if it is too hot put in a higher watt bulb.

Another way would be to take the heating element from a blow dryer or toaster and just straighten out the element and use the same power hook ups they originally had.

[Mike Null]

Joe

Those elements are filled with ceramic. Straightening them will cause the ceramic to fragment and probably the element to break. I doubt it's worth the effort.

[Joe Hillmann]

The one I did straightened just fine, but I also don't think it had any ceramic in it.

Edit: I just looked at an element and it does have ceramic in it, so either the one that I straightened out was different or when it bent it the ceramic broke and it made the entire electrically hot, I never touched it when it was plugged in so I don't know.

[ray hampton]

using a 25 watt bulb will reduce the amps to .25 amp, a clothes dryer heater will work and you can make a number of benders with one coil

[Kurt Hamblok]

Sorry to steal your thread Michael (although it seems you have your solution partially :) ) but what is that notch both Rodne and Frank are talking about? We have to make 300 juwel-displays for some earrings and on our first samples I noticed the "bulging" at the sides of the bend...
Thanks!

[Rodne Gold]

Here is a pic of the notch either side of the bend line , it's an exaggerated picture but shows what I and Frank mean.

[Kurt Hamblok]

Seems logical now, thanks! :)