Anyone know how to do this? I picked up the plastic welding kit from Harbor Freight, but it doesn't have any instructions other than hooking up the equipment. It seems to be pretty much like soldering, but I don't know how to tell one type of plastic from another. I guess I'm going to have to go by feel.

I want to give it a try real soon, my parents keep nagging me for all types of uses for it. ("Can you use your plastic welder thingy on my vaccuum?"). I can't wait to try it.

Mathius

 

mainly there is 2 types of plastics... sandables and non-sandables... the sandanbles are easy to repair since all you need is epoxy to wield them back together... the non-sandanble is where your plastic welder comes into play. Now you can spend alot of time trying to identify which type of plastic you are trying to repair or you hit your average autopart store and ask for a universal plastic rod which will work with any plastic. As for welding, you sand with rough grit (80) the part you want to repair and weild the rod to the dammaged part... if the piece is broken (meaning, became 2 pieces for exemple) you need a reinforcement, somekind of plastic screen (also sold in autoparts stores) which you stick under the pieces to put them back together and add some welding material to keep it welded to the plastic then fill the gaps on the other side...

if I wasn't clear enough, don't be shy and pm me with any question you might have

 

Please let me know how this kit works. It sounds like the perfect kit for fixing my cracks in my dash.

Thanks

 

Okay, I've got one. What are you suppose to use to fill in body indentations like where the "Z28" is on the lower front gfx. I want to fill this, and get some different badges of some sort to put over it. Such as SS badges or something.

 

I would use SEM 39508 Rigid/TPO Repair Material. I used that to shave off my front emblem, and my stock front blinker holes.

I am probably going to do what you are talking about, only just fill in the area, and not put anything there at all.

 

plastic welding is NOT for dash repair... believe me... it won't do a good job.. if you really want to keep this dash professionals are there for it but try to find a new one in a junk yard... as for filling use the universal rod I told you about... takes a bit of sanding but it works great...

note that the gfx's are not made of the same plastic as the bumpers, to repair the gfx's all you need is semi flexible epoxy

 

The SEM Rigit/TPO material IS flexable... will that work? the side GFX actualy seem LESS flexable than the bumper covers.

 

no it won't because you can't weld that plastic... you need epoxy to repair the gfx's you won't be able to melt the TPO and gfx's together... try you will see

 

I'm not quite sure what your talking about... the Repair Material doesn't melt anything, it's kind of like flexable bondo. I used it to fill in my front emblem, just smeared it on like peanut butter, I don't see why it wouldn't work for the side GFX. I don't want to try it if it's not going to work though.

 

ah... then I never heard about what you are talking about.. I know that the bumpers are made of TPO plastic.. meaning that it can't be glued but needs to be welded together... and that the gfx's are of ABS plastics which you can glued together (aka using epoxy) so I can't guaranty you that it will work... but you can attempt a fast repair then try to work the gfx's a bit, twisting them gently (they can hold up a good beating, don't worry) if the stuff hold up you can finish the repair

 

hm... I think I'll head down to the paint supply store, they have walked me through what materials to use so far, they might know about this.

I'll let yall know what they say!

 

cool thanks... keep up posted on your repairs as well.. I'm in the process of bonding the plastic grilles to the fenders and hood and repairing the gfx's myself.... so I know what you are going thru

 

I don't understand why it wouldn't work on a dash? The major crack I have is on the very top center for the vent. It split right on the corner parallel with the vent fins. I also have a few small ones under the dash pad where you can't even see them unless you're looking under it.
If it really won't work, what kind of professionals should I look for to do it?

 

Dash coverings are expanded vinyl. Dash trim is usually ABS (a thermoplastic styrene).

I'm not sure of what kind of "ground effects" parts anyone might be asking about, but some of the factory lower body trim pieces (the ones that look pretty) are usually urethane on older cars, and TEO on newer cars The actual ground effect pieces (the black ones under the front and sides of the car) are PVC or ABS.

PVC, CPVC, TEO, polypropylene, nylon, polyethylene, and ABS can be welded easily. Styrene, GRP, polycarbonate, SMC, and fiberglass resins are a bit more of a challenge. Welding does NOT mean glued with solvent adhesives or bonded with epoxy, but welded with hot filler rod. Thermostetting plastics are usually best repaired with solvent cements or adhesives. Expanded vinyl cannot be welded very easily, and in the thin sections that are used to cover the dash, it would be nearly impossible. Those areas would be better bonded with a colored filler material and matched to the appearance grain of the covering (the professional repair).

If you have any other questions about how to truly weld plastic, check with your local industrial sheet metal fabrication shop. They routinely weld large sections of plastics, including many of those that aren't easily welded, like vinyls and polycarbonates. They would likely be happy to advise you about the type of filler and procedures to use to weld plastic, as long as you don't plan on taking over their business or competing.

If they aren't cooperative, check here:
http://www.urethanesupply.com/howtorepair.html

BTW - Did you get an air compressor and regulator with that "complete" welding kit?

 

yes... what the Sith Lord said

 

The section of my dash that is cracked is definately plastic. I think the only part that is vinyl is the dashpad itself. That's not cracked thankfully. My center vent is cracked and I'm almost cartain it's ABS plastic. I won't be fixing it until this winter when I replace the seat covers, carpeting, and headlinder anyway. I'm planning on painting the dash and console at this time too. I can't wait!

Now if I could just get my engine back together and running before the end of the month I'd be thrilled.

 

My boyfriend plastic welded my front ground effect. I bought it off ebay, the end piece that bolts just infront of the wheel well was missing (looked like it was cut off!). So he cut a piece off a bumper and welded it on.
If you want I'll take a picture & post it, so you can see. I haven't had time to get it painted yet.
On the cracks on the 1/4 pieces & rocker panels, I used 2 part epoxy. It's sandable & works great. Got the idea from a thread on this board.
Good Luck!

 

aiight, the paint guys said the SEM Rigid TPO Repair Material should work just fine for shaving of the Z28 area right behind the front wheels on the GFX.

I'll post up when I get it started/finished Only thing is, it will be covering up some screws, so once I do this, the only way to take the GFX off is to rip it off, or some how cut the other side of the screw from the underside of the car. :-\ maybe this isn't a good idea