HF plastic welding kit

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Zelph

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Hi gang,

Im looking to repair the “plastic”? Splash shield thing that screws into the bottom rear of the front wheel well. Mine is cracked around the mounting screw. Would the Harbor Freight plastic welding kit work on this? Any other ideas for repair? Thank you
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PrairieDrifter

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Plastic welders do work. But the finish isn't there. But on this panel it doesn't matter. So in that case I would just stitch it together with zipties. Drill some holes close to and along the cracks and "x" some zip ties. Been working on my fan shroud for a few years now. Or you can try plastic welding.
 

yevgenievich

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I have done plastic welding decent amount with a cheap kit. It does ok. Go on both sides and get base hot enough and it should do ok
 

Ricko1966

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Drift stitches or some times I'll make a sheet metal backing smear jb weld on it,slap it on the backside and hold it in place with pop rivets. I've also seen people use a soldering iron as heat and zip ties as filler rod to weld plastic. Just like gas welding but zip ties are your welding rod.
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I just looked at your picture,better I'd use a piece of sheet metal jb weld and 4 rivets or sheet metal screws
 
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1lejohn

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I have used JB plastic weld 2 part epoxy in the past. It worked good on my door panels. I also have tried on the splash panel. It holding together on the work bench, have't got around to installing it. I think it will crack again because the panel flexs
 

Camar068

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The problem with plastic welding is if it's old brittle plastic....it'll break again.

That being said, you can try the plastic weld.....but you REALLY need to use the same plastic as the part ur working on. If you use a weaker plastic.....it'll break again. I used the plastic from a grizzly snuff can to repair the wiper fluid jug. The plastic on the jug was so brittle, and the plastic was different than the jug, it just cracked event more.

Also, you have to keep in mind if this is a part that flexes a lot, you may need to go with a 2 part epoxy. Normally, 2 part epoxy is pretty rigid so your repair won't break there....but may elsewhere.

Not affiliated with them, but you may be able to use Total Boat to repair it as a last resort. Google it and research it.

I mixed some up and poured it out on the table and let it dry for a few days. It was very rigid. I then took a heat gun to it for about 30 seconds or so. I was able to bend the 6" piece in half and touch the other end with out it breaking/cracking.

Just a thought if that part is really worth it to you.
 

Ricko1966

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If you've ever patched a tire you will understand this,fixing something like that I bond a piece of metal across the broken area on the backside. I bond it with jb weld and hold it in place with sheet metal screws or pop rivets it will not break there again.I guarantee that.
 

justhorns

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Have you considered buying a repop part from LMC or someone like that? It may be cheaper than repair.
 

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Splash shields are $15 from LMC. Like a sore d**k, can't beat it! Why bother trying to repair the old brittle ones?
 

SirRobyn0

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I've done a fair bit of plastic welding. On the farm I have one of those harbor freight plastic welding kits. Like welding metal there is a technique and it's kind hard to describe the how to, but you must have good penetration. With thick plastic sometimes it's best to try to weld from both sides going about half the depth on both sides. You HAVE to have filler material that is the same type of plastic being welded. If you use a different type of plastic for filler than you are welding it simply won't stick together and will make a mess. If it is at all possible to sacrifice a bit of plastic off another area of what you are welding that is what I like to do.

As for the kits, the HF kit does ok, my biggest complaint is that it is slow. As in it'll take you some time to fix a piece of plastic like that and it's not all that hot so it's unlikely you'll smoke it. At the shop, we have a table top soldering station was like a $500 setup 10 years ago. I bought tips for the soldering station for doing plastic welding and that thing is awesome to use. It gets plenty hot and easily melts the plastic, you can change heat settings to what you want, but of course it'll get hot enough to fry your plastic. It does take some practice to get good at plastic welding but once you get it down it'll be stronger than any adhesive and you can get the finished product nice and smooth which is great if it's something that will be seen. Hit the rest of the plastic with a heat gun or some fine steel wool with a lubricant, (like soapy water or mild cleaner) and next thing you know it'll look almost new, but yes it takes practice to get to that point.

The biggest problems are, if you overheat the plastic it'll be brittle, (unlikely to do that with the HF kit). And if the plastic is brittle it may break again nearby, but you can get really artistic with it and reinforce if from the back side.

However for your repair I'd drill a small hole at the end of the crack, and use epoxy and probably drill a couple more holes to run zipties in to strengthen that area. It's a simple solution, that doesn't require you learn a new skill that in all likely hood you'll seldom use, and it's for a part that isn't really seen. If you have the extra cash at $15 it might just be best to replace them, but for me I can't afford nothin' extra without working extra, so I'd probably repair the existing ones.
 

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3M Panel Bond Epoxy will work if you first treat/prep it like a regular metal weld.
 

Ontheboulder

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I have done this before, use a good 2 part epoxy, v groove the cracked area and drill the hole at the end of the crack. Then clean and lightly sand down the plastic 2-3 times larger than the crack area then wipe down with rubbing alcohol and epoxy the whole thing. Make a mark in an area that you won't cover with epoxy to re drill the holes. your phone camera works good for this part! good luck
 

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Splash shields are $15 from LMC. Like a sore d**k, can't beat it! Why bother trying to repair the old brittle ones?
That was my thought...
 

SirRobyn0

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I have done this before, use a good 2 part epoxy, v groove the cracked area and drill the hole at the end of the crack. Then clean and lightly sand down the plastic 2-3 times larger than the crack area then wipe down with rubbing alcohol and epoxy the whole thing. Make a mark in an area that you won't cover with epoxy to re drill the holes. your phone camera works good for this part! good luck
This is a really good technique and I did this on the plastic tank of my Dodge truck's radiator about 8 years ago. Just re-did it because it started seeping a little. I'd say that's pretty good. Oh, and I used JB weld.
 

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