Plastic Welding?

[Trails2004]

Trails, Snow skis? We are professional ski instructors, wife and I. Nicole is a Senior Examiner for P.S.I.A. Time for dinner.

Yep- In my younger days- I'm really not that old I raced in the Northern Divsion( Wyo- Mont)- I really had a blast-We always were tuning our skiis-which often included fixing gouges in the base with p-tex.

My boards are a little old-I'm still able to ski most (to be read most ) terrain-

 

[valley]

Trails, Thing is not many people even know what P-Tex is. I just dressed {tuned} wifie's skis for an event she is doing Monday. I was looking for Nicholson files Yesterday but only Chinese could be found and at Nicholson prices.

 

[valley]

Well! Thanks for the thoughts. Sounds like they[plastic welder] are good for thicker plastics and having the correct rod is the main concern. Didn't sound like many guys have gotten into plastic welding.

Is ABS usually black? The material that tool containers are made of looks like PVC as do plastic lawn chairs. I don't see anything around that looks like nylon.
Do you actualy touch the tip to the work?

 

[ray66v]

Yes, Abs is usually black. It also will soften with acetone, or lacquer thinner.

Abs is more easily solvent welded.

There are also hybrid mixes that have strange properties.

 

[ALKY]

If you're lucky the plastic has a recycling # to help id it. alot of black toolboxes are hdpe [#2]. years ago i welded plastic almost everyday at work. we did rehab on manholes for dupont,bfi,ect. you don't want to know what was flowing through them!

 

[DiskDoctr]

I also have the HF unit. It can make strong welds, but not always pretty.

Here are some tips:

1. Notch the crack in a V shape where you are going to apply the weld (from the back when you can)

2. Keep the extra pieces you cut off and use them in the weld. This is the right kind and color, for sure

3. Try to weld from the back. If the pieces are put together very closely and held well while welding from the back, any front crack will be hardly noticeable

4. Have some type of "spoon" available to push/shape the plastic while still warm. These are more like hobby tools than a table spoon and are different sizes/shapes.

5. DO NOT OVERHEAT THE PLASTIC !!! Better to heat and weld, let cool and do some more. When you over heat, it will burn and/or shrink and make a mess. No burnt marks (bad!)

6. When using the rods, I've had the best success when cutting pieces and laying them into the V notches above, then heating. Sometimes better to place the pieces in the V before heating, sometimes have the pieces cut, heat the work material, then put the pieces in the void and heat. Depends one what and how you are welding.

7. Make sure everything is VERY CLEAN. Just like soldering, oils, dirt, etc will interfere with the bonding and results.


I've used this for repairing broken body panels on ATVs, motorcycles, etc. Along with a good heat gun to heat and take out kinks and bends, it has been a handy item.

Hope this helps!

- JC

 

[smiley]

I had to do a quick repair on my son's 4 wheeler plastic plow blade. After trying an electric soldering gun which didn't heat a large enough area to be effective, I remembered a soldering tip I had never used, for a berzomatic torch. Got it out and after some experimenting, found I could lay it across the crack and stitch it together and it looked like frankenstein stitches but held it together and finished the job. Several days later, I picked up some of the rods at HF and melted them into the stitches just to fill it and the thing is still together 4 or 5 years later.

 

[gerard]

discdoktr gives some very good tips. I have the same unit and have found that matching the plastic is a must. The easiest thing is to use some scrap plastic from the same source as filler. ie I keep a broken plastic water bucket around so when another one breaks, I cut slivers from the one bucket to repair the other one. Finding the right melting temp is important also. I broke a running board on our F250. Would have been $500 for a new one. I was able to jigsaw fit the pieces back together and did a tolerable enough repair that you wouldn't know it was broken unless I pointed it out to you. Paid for itself many times over, just takes some practice. (Though I find metal welding easier).

 

[David Devuono]

Interesting reading. I have done many plastic welding projects just using a soldering Iron, will have to remind the wife I really am patient. Anyway people must be wondering who the crazy guy picking up broken sled pieces from the snow hill is. I have welded Fender liners, modified plastic air boxes by welding in larger inlets. Recently welded back on the plastic tabs to a head light after Junior had an accident. My biggest project was cutting up and rewelding a Fan shroud after putting a body lift on a 4x4. I have never has a piece break during regular use but its nice to know there are special welders for this stuff.

 

[valley]

Thanks guys for the info and feedback. Does anyone use a unit that has only a open tube tip? This welder has no paddles. The use of a spoon was mentioned in one post.
We have these heated water buckets in the barn, its only a mater of time when one will need repairing.

 

[DiskDoctr]

Thanks guys for the info and feedback. Does anyone use a unit that has only a open tube tip? This welder has no paddles. The use of a spoon was mentioned in one post.

That confusion is my fault. The one I have only has the open tube tip as you mention. The spoons are anything you can use that will take the heat. You can get some that are shaped like dental tools but have different shapes and sizes of ends.

These are often used for leatherworking tools, such as here:
Modeling Tools: One Stop

Sorry for the confusion.

-JC

 

[valley]

Hi, I've been away, sorry. There was no confusion, you discribed it well. I'm not sure I want to use this welder or take it back for some other tool. Once I use it , its mine.

 

[DiskDoctr]

If I were doing it again, I'd go for the more expensive unit with built in air (no compressor needed). The basic version I have uses a lot of air, and this ties me to using it in the main garage.

But that is because I like it and would surely use it more if I could use it in the nice heated basement

- JC

 

[valley]

That makes sense! I was looking at that one on line. I think they are $80 smackers.

 

[mojoinco]

I had one of the HF welders (the one Valley mentioned, I believe). They really mean it when it says to have air moving through it when it is turned on -- oops. Worked okay for a $25 welder. I left mine to heat up while researching welding up holes my wife drilled in her brand spankin'h new water tank (told her they looked like husband holes to me -- she was drilling drain holes in her new horse trailer floor). Anyhow, you can use ldpe for hdpe and vice versa (#2 & #4 recycle symbols iirc). I ended up using a rubbing alcohol container (it was clean) and an old iron I keep for fixing dents in wood. Came out perfect. I found the info surfing the web ('plastic welding'). The tank manufacturer replied to an email for the tank material type.

 

[gerard]

Thanks guys for the info and feedback. Does anyone use a unit that has only a open tube tip? This welder has no paddles. The use of a spoon was mentioned in one post.
We have these heated water buckets in the barn, its only a mater of time when one will need repairing.

I've fixed some heated buckets. I just use a screwdriver as the paddle to mash the plastic together and smooth it out.

 

[J_J]

Here is a description for the use of the gray, green, and the white rods.

- Harbor Freight Tools - Quality Tools at the Lowest Prices

 

[busydaddy]

there was an article in homa shop machinist about plastic welding. A router style control was used to lower the voltage of the tip. The writer also mde his own rods out of abs pipe by cutting it into square strips with a band saw.
It really did a nice job but some practise is a great idea first

 

[valley]

With all there is to do' I haven't tried it out yet. When I get to it I'll post what I find.