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6bt
08-26-2017, 01:39 PM
Anyone ever have any luck plastic welding? My 86' 250r still has it's original front fender with some cracks. Was thinking about taking it to a auto body shop, and see if they would plastic weld it from underneath. Has anyone tried this? Does it hold up long term?

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Dirtcrasher
08-26-2017, 02:52 PM
I've seen a guy buy an expensive Snap-On plastic welder and even that didn't cut the mustard.

I am yet to see someone repair plastic in a manner that holds up and looks decent.....

knappyfeet
08-26-2017, 03:07 PM
Anyone ever have any luck plastic welding? My 86' 250r still has it's original front fender with some cracks. Was thinking about taking it to a auto body shop, and see if they would plastic weld it from underneath. Has anyone tried this? Does it hold up long term?

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The problem with welding TPO, PP, PE, etc style plastics is they distort the shape. If it's colored it will distort the color. Auto body shops use plastic welding for heavy injected molded abs but since PP type plastics are a different breed.....I don't know. I think most autobody shops now mainly replace the plastics rather than repair as most work is insurance work.

I repaired my front fender of my 200X. It's not pretty but to me it's WAAAY prettier than zip tie repairs and way cheaper than replacement.

http://www.3wheelerworld.com/showthread.php/182167-1985-Honda-200X?p=1451463#post1451463

HarrisoN*
08-26-2017, 09:38 PM
Plastic welding isnt all that its hyped up by the companys that sell the welding kits or people who claim to do it.

like said, its pretty much useless on coloured plastics, you will always see the repair unless you paint over it. I work in autobody and do 90% of the bumper replacements or repairs that come thru our shop (30-50 cars a week). We do not even have a plastic welder simply because theyre junk, repairs do not hold upto stress/strain. We only repair by worse case melting cracks or splits with a soldering iron and then reinforcing with 3M products. Insurance companies want shops to plastic weld and repair alot of jobs but its simply not worth the risk of putting the bumper back on and a repair failing so in most instances we just replace.

my advice to you would be; clean the item real good, free from dirt and debris. Buy a quality soldering iron, something with a variety of tips and variable heat control. Personally portasol are good, butane is a plus. Sears usually have some which you can pick up with coupons online for like $50-70, smae thing would be $200 on a tool truck rebranded.

then practice on some old fenders, you want to hold the crack closed and start at one end just lightly sink the hot tip in, repeating along the crack. allow to cool whilst still holding the item together, the item should now hold on its own. once cool after a few seconds repeat, trying this time to smooth out the indents you put in. keep repeating until the crack/groove is filled.

difficult to explain but im sure theres a variety of stuff on youtube. Key is not too much heat, and light pressure. Ive heard of guys using wire ties like filler rods and using gorilla glue to hold cracked items to start with.

Shawn Powell
08-26-2017, 11:43 PM
JB weld from the bottom and color sand the top side after dry. Personally if it's a rider sell the oem fender and buy maier. (Or some of those fancy carbon fiber ones of you got baller dollars)


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sledcrazyinCT
08-27-2017, 07:24 AM
I bought one from Harbor freight and it works okay. I would recommend using them to fix beater plastics only. I used cotter pins cut into pieces to use like a stitch, laying across the crack. The little strips of metal sink onto the plastic and help keep the crack from spreading apart.

BIG RED MARK
09-11-2017, 04:04 PM
Just restored some rear fenders on a 1983 Honda BIG RED 200E and had to do some plastic welding. See attached link to forum thread for before and after pics. For me plastic welding holds up great but you cannot hide the repaired area without painting the plastics which has drawbacks.
http://forums.justbigreds.com/post/1983-honda-big-red-200e-restoration-8228149?&trail=60

350for350
09-11-2017, 10:14 PM
HarrisoN. What kind of 3M products are you talking about? Anything like the Valvoline 8001 that I ordered last night?

NeverLift
09-12-2017, 12:15 PM
http://www.3wheelerworld.com/showthread.php/165358-Help-cracked-fenders-ideas-how-to-repair?highlight=plastic+welding

look thru this thread lot of good info. post #20 has a video of me welding. 3 years ago and its still holding strong.

Ol Deuce
09-12-2017, 01:17 PM
I use a Hot Air welder and cut up old red fenders for the filler!! It works well for me! I do it all from the back side and keep the heated area to the crack only.

Ol Deuce

jensenracing77
09-14-2017, 09:43 PM
I have gotten into some plastic welding and it can be done so that you can't hardly tell it was done. The problem is, to do it right it is VERY time consuming. Most people are not doing it right. Don't get me wrong, I am still not an expert but do know enough about it to know what can be done. I just welded a ripped out hole in a set of Oldsmobile 442 W-30 inner fenders. I don't have a finished picture on the computer but you can see that it is possible. This is a $4500 set of fenders I was welding on and charged a pile for doing it. You would not want to pay someone to do it on a 3 wheeler fender if it was not an expensive restoration. You are better off getting a welder and practicing till you feel good about it and try it yourself.

TrailerRider
09-15-2017, 04:42 PM
I do some plastic welding with my soldering gun. Its holds up alright. The only way to hide the seam imo is to build the repair high, sand it smooth then take the heat gun and work even heat across the area. The heat will smooth the plastic and hide the repair BUT you can ruin the repair if you get to hot and cause the plastic to become brittle. Using the heat gun works to bring color back but that's is a serious skill..lol.

TrailerRider
09-15-2017, 04:52 PM
Here is a fender I just did recently. It was cracked, broke, brittle, sun faded and had that build up on the plastic you can scratch off with your finger nail. The fender was junk. I kept it around for extra matching material for filler. Got bored and wanted to see if I could get it back to a rider plastic status. I did no prep to it aside from using a wet towel to wipe it clean. *Most* any plastic can be brought back to useable format but making it show quality.. Leave that to the pro's (which I am NOT lol!).

https://thumb.ibb.co/hAu28k/20170908_132051.jpg (https://ibb.co/hAu28k) https://thumb.ibb.co/e1rRZQ/20170908_132135.jpg (https://ibb.co/e1rRZQ) https://thumb.ibb.co/j5sB15/20170908_134127.jpg (https://ibb.co/j5sB15) https://thumb.ibb.co/cMPr15/20170908_134141.jpg (https://ibb.co/cMPr15) https://thumb.ibb.co/naivTk/20170908_173619.jpg (https://ibb.co/naivTk) https://thumb.ibb.co/kZXpok/20170908_173625.jpg (https://ibb.co/kZXpok) https://thumb.ibb.co/nRdUok/20170908_173634.jpg (https://ibb.co/nRdUok)