Bending Plastic Tubing

[Mooneyzs]

I am curious as to how everyone out there bends their plastic tubing. Been trying to think what the best method is to bend tubing.... Is it heating in warm water, heating with some sort of heat gun/wifes hair drier, bending it cold....etc I am also wondering if making jigs to bend the parts are a good idea as well. Let me know what you all think. Thanks

[Casey]

Use a coiled tubing bender to bend warmed tubing.

[Mooneyzs]

Thanks Casey....I didn't even think of using a coiled tubing bender.

[highway]

I use plastistruct tubing with a brass rod inserted inside, tubing will hold its shape with no problems

I was thinking the same thing!

[Wagoneer81]

I found a great way to bend plastic tubing without using up a brass or aluminum tube in the process. (Some of us are cheap like that... )

I think I actually learned this technique here... I don't remember...

Cap one end of the tube with a piece of plastic and a bit of superglue, fill the tube with regular table salt and cap the other end so the salt doesn't run out. (cut a longer piece than you need, you'll cut it to length when finished bending.) The salt will help the tubing hold its shape when you bend it. I slowly heat the area to be bent over a candle flame (this is a personal preference, others may use a different method.) and shape accordingly. after the tubing has cooled, cut one cap off, pour the salt out, trim the tubing to shape and there you have it. I've done truck exhaust with this method and it looks just like miniature, mandrel bent pipe.

Hope this helps!

[shucky]

The filling the tube with something trick (like sand or salt) was meant to prevent kinks in bent aluminum tube. Not sure how beneficial or necessary it is when bending styrene tube. When at room temp, styrene is fairly flexible. It can be bent and coiled quite easily. If finessed with just the right amount of tension it will actually stretch slightly to accommodate very tight bends. Normally though, it does not hold it's shape without some additional tubing inserted inside as others have pointed out OR it being bent using heat which is the method I prefer. Inserting tubing inside has it's limitations depending on how tight your making a bend and of course the shape your trying to achieve. You can make quick work of bends using very light candle flame heat and some practice.

[diymirage]

i have a little peice of wood with two nails sicking out of it

whenever i want to bent the styrene i place it in between the nails and one nails acts to hold the styrene in place while the other acts as a point to bend around

this way my radius is the same every time

[Mooneyzs]

Thanks everyone for all of the great tips. I have bent tubing a few ways but I am going to try some of these new Tips to see which I like the best. I appreciate all of your help, Thank you!

[Wagoneer81]

The filling the tube with something trick (like sand or salt) was meant to prevent kinks in bent aluminum tube. Not sure how beneficial or necessary it is when bending styrene tube. When at room temp, styrene is fairly flexible. It can be bent and coiled quite easily. If finessed with just the right amount of tension it will actually stretch slightly to accommodate very tight bends. Normally though, it does not hold it's shape without some additional tubing inserted inside as others have pointed out OR it being bent using heat which is the method I prefer. Inserting tubing inside has it's limitations depending on how tight your making a bend and of course the shape your trying to achieve. You can make quick work of bends using very light candle flame heat and some practice.

I used the salt technique on 1/4" dia. thinwall styrene tubing because I was getting some pretty bad deformity at the bends when I was heating and bending. These were pretty tight bends as I was trying to route the pipe up between the frame rail and the fuel tank between two of the tank mounts on a 1/25 scale Titan90. I wasn't having any luck doing it any other way and using the salt just made it sooo much easier... I've used these other methods as well with smaller tube and I'm not disputing that they all work quite well. The method of using the brass insert wire in the tubing is the most painless way to bend small diameter tubing that I've ever used. Now that you mention it, I can see salt or sand not being necessary on smaller stuff. I should have specified what diameter tube I was using, I guess.

Edited March 4, 2011 by Wagoneer81

[shucky]

Chris no worries, we all learn everyday! Something to keep in mind, for really tight bends regardless of diameter use solid styrene rod not tubing. It really prevents a lot of the problems associated with bending.

[Mooneyzs]

Chris no worries, we all learn everyday! Something to keep in mind, for really tight bends regardless of diameter use solid styrene rod not tubing. It really prevents a lot of the problems associated with bending.

yea a couple things that I want to bend will end up being solid styrene for a 1/25th scale super comp dragster frame (which is a future build but have had the idea for a few years now). then others are for some 1/16th scale drag kits as well as roll cages for some muscle/pro streeet car kits.

[Wagoneer81]

Chris no worries, we all learn everyday! Something to keep in mind, for really tight bends regardless of diameter use solid styrene rod not tubing. It really prevents a lot of the problems associated with bending.

Yeah, I didn't even know they made solid rod that diameter. I'll have something to talk to my LHS about... "Hey, Brandon, can you get..." Solid rod would have been nice but...I had to use what was on hand. Clint said it best in 'Heartbreak Ridge', "Improvise, overcome, adapt." No worries is right, we're all here to learn in one form or another, that's one of the many reasons that I love this forum!