Hoosierdady
Fan of wheelspeed
☆ The Chop Shop What Glue to Use For Body Work/Repairing Cracks in Plastic and Why ☆
Hey guys "thumbsup" So I get this question almost every other day so I figured I would just put this out here for everyone to see. So if you have questions or comments feel free to ask. I'm not giving away all of the trade secrets
but I'll help out as much as I can. Please keep in mind that I DO NOT claim to be a expert on this subject. But I have done tests with styrene as well as scrap plastic pieces from a Hilux to test these glues and these methods so I know what happens to the plastic when you do the following to them.
I use three different glues for my body work :shock:. Three different glues because each one has a different compound to cover every range of rigidity. Starting from the top.
Bob Smith Industries (BSI) CA glue
CA glue is a external glue. It will somewhat heat up the plastic alone, but not enough to really even tell. CA glue by itself is very brittle (unless you buy the flexible stuff) so it isn't all that strong by itself. Keep in mind, this is the brittle glue. I use Insta-set CA accelerator with it and that literally heats things up for a instant and strong bond. It will get hot enough to emit smoke and can burn your fingers. Watch your eyes and inhaling too.
It'll also help keep the plastic or tire from turning white after it's cured. IT WILL NOT 100% PREVENT that from happening, but it does a great job of keeping it to a minimum.
Next, Plastruct Bondene or Tenax 7R
The Bondene/Tenax7R is a plastic welder. It melts the plastic so that you actually get a true bond for the two sides. It takes a while to cure, but once it does you have a fairly strong bond. Keep in mind, this glue isn't brittle nor flexible. It merely melts the two halves together so you have a bond that is juuuust a little weaker than the whole unit would be if it hadn't of been cut at all. The joints will still be stiff if you used a wider "glue contact" area. But simply because it is now thicker than the whole sheet of styrene/body/etc was. When you get a true bond with this glue it will actually rip the styrene when you try to peal the halves back apart. If you do a "butt joint" using this glue it won't hold up very well. As I said before it's just a little weaker than it was originally, but thats enough for it fold easily.
And finally the ShooGoo or E6000.
As you know, these two adhesives are rubbery. The get pretty firm but you can bend it all over and even peel it off if you try hard enough. This glue is the glue of all glues for a RC nut. It is the MacGyver of glues.
If Chuck Norris and Macgyver had a glue baby...it would be named Shoo Goo or E6000 :shock:. Ok, enough of that...back on track.
It will hold two halves of plastic/styrene together just fine by itslef. But its not sandable and you can't do any body work because of how flexible it is. When you paint on top of styrene or plastic that has been joined by ShooGoo/E6000 you can fold the styrene like a hinge, so the paint cracks. Both of these glues will shrink when fully cured. If you were to layer two sheets of styrene together using either of these glues to bond them it will shrink far enough to cause the styrene to wrinkle up like you fingers when they've been soaked in water for an extended period of time. If you use it on painted lexan, it will pull the paint off of the lexan unless you have lightly sanded the lexan before painting to get a super strong bond. Keep this in mind when modifying lexan bodies or attaching the front ends on certain bodies where they're made seperate.
So why all three?
Take any ONE of those glues and try to make a bond or glue two halves of plastic together edge to edge (No overlap, just a butt joint). The CA glue will crack when bending the two. If you just gob it on it'll hold, but it'll look like sh!t. Sand it down as it should be and it's going to snap the first time you hit something or have a roll over. As for the Bondene/Tenax7R, it by itself will hold to an extent. But it isn't a very strong glue for butt joints, only for over lapping joints do you see any real strength with this glue. Some people will mix minced rubber bands or fine shreds of styrene to create a thicker paste like substance, and that works pretty good. But not as good as this 3 glue method. Finally, the ShooGoo or E6000. When you make a butt joint using this glue it literally folds like a hinge. The is no rigidity there. By using these three different glues you cover all three areas. You have everything covered from the brittle end of things down to the flexible end of things. IF you smack a rock hard enough to break thru the CA glue a.k.a. "the hard shell brittle plastic" and the Bondene a.k.a."the somewhat weakened plastic" then the Shoogoo "the rubbery hinge" will still hold the two pieces together. I've had my rigs roll down 2 ft of rock end over end, down 10ft worth of hills in comps, you name it and the only thing that breaks is the virgin plastic. If I repair the broken spots with this method that spot will NOT break again unless you really try at it.
I hope that helps. As I said before, feel free to ask any questions on this thread "thumbsup". Don't be afraid to chop up a $100 body, it's only plastic. If you decide that it's not worth it for you to mess up a expensive body...I happen to know a guy. :mrgreen:
Hey guys "thumbsup" So I get this question almost every other day so I figured I would just put this out here for everyone to see. So if you have questions or comments feel free to ask. I'm not giving away all of the trade secrets
but I'll help out as much as I can. Please keep in mind that I DO NOT claim to be a expert on this subject. But I have done tests with styrene as well as scrap plastic pieces from a Hilux to test these glues and these methods so I know what happens to the plastic when you do the following to them.I use three different glues for my body work :shock:. Three different glues because each one has a different compound to cover every range of rigidity. Starting from the top.
Bob Smith Industries (BSI) CA glue
CA glue is a external glue. It will somewhat heat up the plastic alone, but not enough to really even tell. CA glue by itself is very brittle (unless you buy the flexible stuff) so it isn't all that strong by itself. Keep in mind, this is the brittle glue. I use Insta-set CA accelerator with it and that literally heats things up for a instant and strong bond. It will get hot enough to emit smoke and can burn your fingers. Watch your eyes and inhaling too.
It'll also help keep the plastic or tire from turning white after it's cured. IT WILL NOT 100% PREVENT that from happening, but it does a great job of keeping it to a minimum.
Next, Plastruct Bondene or Tenax 7R
The Bondene/Tenax7R is a plastic welder. It melts the plastic so that you actually get a true bond for the two sides. It takes a while to cure, but once it does you have a fairly strong bond. Keep in mind, this glue isn't brittle nor flexible. It merely melts the two halves together so you have a bond that is juuuust a little weaker than the whole unit would be if it hadn't of been cut at all. The joints will still be stiff if you used a wider "glue contact" area. But simply because it is now thicker than the whole sheet of styrene/body/etc was. When you get a true bond with this glue it will actually rip the styrene when you try to peal the halves back apart. If you do a "butt joint" using this glue it won't hold up very well. As I said before it's just a little weaker than it was originally, but thats enough for it fold easily.
And finally the ShooGoo or E6000.
As you know, these two adhesives are rubbery. The get pretty firm but you can bend it all over and even peel it off if you try hard enough. This glue is the glue of all glues for a RC nut. It is the MacGyver of glues.
If Chuck Norris and Macgyver had a glue baby...it would be named Shoo Goo or E6000 :shock:. Ok, enough of that...back on track.
It will hold two halves of plastic/styrene together just fine by itslef. But its not sandable and you can't do any body work because of how flexible it is. When you paint on top of styrene or plastic that has been joined by ShooGoo/E6000 you can fold the styrene like a hinge, so the paint cracks. Both of these glues will shrink when fully cured. If you were to layer two sheets of styrene together using either of these glues to bond them it will shrink far enough to cause the styrene to wrinkle up like you fingers when they've been soaked in water for an extended period of time. If you use it on painted lexan, it will pull the paint off of the lexan unless you have lightly sanded the lexan before painting to get a super strong bond. Keep this in mind when modifying lexan bodies or attaching the front ends on certain bodies where they're made seperate.
So why all three?
Take any ONE of those glues and try to make a bond or glue two halves of plastic together edge to edge (No overlap, just a butt joint). The CA glue will crack when bending the two. If you just gob it on it'll hold, but it'll look like sh!t. Sand it down as it should be and it's going to snap the first time you hit something or have a roll over. As for the Bondene/Tenax7R, it by itself will hold to an extent. But it isn't a very strong glue for butt joints, only for over lapping joints do you see any real strength with this glue. Some people will mix minced rubber bands or fine shreds of styrene to create a thicker paste like substance, and that works pretty good. But not as good as this 3 glue method. Finally, the ShooGoo or E6000. When you make a butt joint using this glue it literally folds like a hinge. The is no rigidity there. By using these three different glues you cover all three areas. You have everything covered from the brittle end of things down to the flexible end of things. IF you smack a rock hard enough to break thru the CA glue a.k.a. "the hard shell brittle plastic" and the Bondene a.k.a."the somewhat weakened plastic" then the Shoogoo "the rubbery hinge" will still hold the two pieces together. I've had my rigs roll down 2 ft of rock end over end, down 10ft worth of hills in comps, you name it and the only thing that breaks is the virgin plastic. If I repair the broken spots with this method that spot will NOT break again unless you really try at it.
I hope that helps. As I said before, feel free to ask any questions on this thread "thumbsup". Don't be afraid to chop up a $100 body, it's only plastic. If you decide that it's not worth it for you to mess up a expensive body...I happen to know a guy. :mrgreen:
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