plastic welding

[porthos]

anyone ever use any of these devices? priced from $25.00 to $50.00 +-. some use some type of staples and i see some with plastic "welding rods". anyone have experience/thoughts??

[NY_Treeguy]

I have used the harbor freight welder. Works OK providing you can match the base material to the rod type.

[Shawlerbrook]

Thought about it on an old ATV but ended using fiberglass mesh and resin.

[jsizemore]

I had a friend that made a living repair auto bumpers. I was amazed at the covers they repaired especially the ones they welded. I never did the work myself.

[rbuck351]

I have used an old soldering iron and I try to cut pieces of plastic off an unexposed place on the part I'm welding. I have used hot glue and the iron for fill out but the original plastic works the best.

[15meter]

There is a product out there called Ptex, you can buy it on amazon.

You would light this plastic rod(the Ptex) and it would drip molten plastic.

I used to use it to repair the plastic bases on downhill ski's.

The molten plastic would be hot enough that it would melt into the base then cool into one piece. You just dripped the molten plastic where ever you need it, then trimmed off the excess.

Hard to tell the original from the repair material.

A couple of weeks ago I repaired the corn head for a John Deere toy combine for my great nephew. If I had green instead of the black ski base repair Ptex, it would have been difficult to find the repair.

One happy 5 year old.

Need to pick up another stick or two of Ptex, used my last fixing the corn head. But Milo got the corn in so it's all good.

It will repair most thermoplastic type plastics. Think milk jug polyethylene. Never tried it on the polystyrene kind of plastics.

[tommag]

I use one occasionally and like it. Mine is from harbor freight. Make sure you use rod that is the same as your substrate. I bought mine to repair a blackwater tank on a travel trailer. The tank was hdpe and I had to find the hdpe rods elsewhere. I practiced on a 5 gallon bucket (usually hdpe) before repairing the tank.
After using, put the heat level to 0 and let it run a while to ensure cool down. Not cooling the heat gun properly will damage it.
Also, treat it like oxy acettaline welding. Use a carbide burr on a dremel to clean and v the surfaces to be welded.

[Minerat]

In the past you could ger the Ptex in colors at many ski shops. Now a days you only see black or clear once in a while. I have a blue one for my o!d Nordica Grand Prixs

[PhilC]

I repaired a lot of plastic bumpers during my time as a collision tech but never welded any.

[Huskerguy]

Back in the day, up until 1999 when I got out of it, I was teaching auto collision in a college and this was one of the courses I taught. That has been a long time ago and materials have become much better but the basics still apply. There are two types of plastic, thermo plastic and thermoset plastics. Then determine what type of plastic you have, usually there is a symbol on it somewhere but not always. In the case where you don't know there are some tests you can perform for adhesion and burning, etc. Be careful breathing that stuff. Once you figure out what you have, then it is either welding with heat and possibly a rod of matching material or you use adhesives made for it. It really isn't all that difficult to do, either process, once you figure out what material you are working with and then get the corresponding repair material. Google two different types of plastics and you will find a ton of information.

[GregLaROCHE]

I don’t know about bumpers, but I’ve repaired a lot of cracked plastic items with a soldering iron.

[MaryB]

Did some HDPE welding making custom tanks for a feed testing lab. RO water and chemical tanks for workstations. Bevel the area, apply heat and rod and "weld" it by moving the rod side to side to fill in the V.

[Shopdog]

Have fixed factory ABS sportbike bodies with a soldering iron and zip ties as the filler. Works WAY better than has a right to.

[MT Gianni]

I put miles of gas pipe together with plastic welding as the factory referred to it. Control your temps, watch your melt and pressure hold the two together. Done properly it is the same strength as new. Done by the untrained, with little attention to detail and you can knock it apart with a ball bat.
As with a lot of welding the ability to have a pretty finished product is not necessarily equal to having a great weld.