Plastic repair

[retrex]

Just got new plastic welder from Harbor Freight, about $40.00. Repaired front fender 81 GS11. It works but it takes practice. Plastic welding rods that came with it didn't work. If there is anyone interested I will post more info.

[Jethro]

If there is anyone interested I will post more info.

Yes please.

[retrex]

From another Forum I participate in

Welder operation; Looks like a larger version of a pen type soldering iron.

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=41592

Hot air supplied from a compressor passes through heated coils and out of a pointed tip. Unit has it's own pressure regulator. Comes with different types of welding rods.

I was able to test out the welder this weekend. Findings are that it does work. I welded back on the hinge to my S10 glove compartment door. It was delicate work. I have tried a number of glues in the past and nothing was permanent. Sanded off the glue with dremel and heated plastic to melting point and joined pieces together. Looks horrible, but then all my welding does, but it looks like it will last for the remaining short life of the vehicle.

The second test was on a front fender from a GS1100. White plastic under the paint. The crack was about 7 inches long, jagged, from one side of the fender across to the other. The two halves were fully detached, or separated along the crack from one side of the fender to a non broken end on the other side. It was a flapper. In the initial attempt I tried to apply white welding rod material to the joint while welding. It was a waste of time. The rod material came off the weld but the weld area itself was sound. The rods make nice non stick probes to push the molten base material around but are good for nothing else. I inflicted too much damage in a second attempt at trying to get the rod material to reinforce the fender substrate. They don't even stick to themselves when melted. Turns out the joint doesn't need to be reinforced after welding. I picked it up by short end and waved and shook it about without any damaging to the welded area. Perhaps the more expensive Eastwood rods will work better. The welded joint on the fender seems to be sufficiently strong to be put back into service. I should have stopped at just heating and joining the broken ends together. Unfortunately I over heated and warped it a bit trying to get the rods to work. All in all I think that it will work if you have the two parts to weld together. It is doubtful that you will be able to weld two parts together unless the materials are identical. Maybe the Eastwood rods work better that the ones I got with my welder. I'll check on this at a later date.

It's necessary to use the exact same material as the damaged job, so those rods that may look the part, obviously are not. One complete side cover may have to be sacrificed to provide rods, or maybe a narrow strip could be cut from the lower edge that's not redily visable.

tombatt

I thought of that tombatt, I had another fender, grey material this time, where I cut off a sliver of the fender to see if I could add that material into a weld pool of itself on the fender. I was not entirely sucessful. I got it to stick a little better to the weld pool, but was not able to add an appreciable amount of material to the pool before a significant distortion of the fender took place. I think that it may be possible to do as you suggest but it may come down to prevailing substrate thickness, melting point, and skill of the user. I will probably get better with practice, and I have plenty to practice on, but until I become proficient I'll stick to post building using the above mentioned techniques on cosmetic pieces.

[Jared]

The dif manufacturers use different flavors of plastic for their body parts on the bikes... so you need to figure out which sticks work with what manufacturer...Not sure which is used most...( ABS ..PolyCarbonate..Polyethylene.....the list goes on..)add in the age of your plastic part and that may be different...

Some methods just use a reinforment mesh that gets welded into the part and then you use a fill.... But you probably know all of this already...

Good Luck...

[retrex]

Information appreciated

The dif manufacturers use different flavors of plastic for their body parts on the bikes... so you need to figure out which sticks work with what manufacturer...Not sure which is used most...( ABS ..PolyCarbonate..Polyethylene.....the list goes on..)add in the age of your plastic part and that may be different...

Some methods just use a reinforment mesh that gets welded into the part and then you use a fill.... But you probably know all of this already...

Good Luck...

Thanks for the input, I had fogotten about the mesh. I haven't given up on using weld rod material to reinforce the weld, just using the rods that I purchased with the kit. Anybody want to buy flexible chopsticks?