It never fails to crack me up.

[ribbert]

Much has been written here over the years on plastic welding and some of our members have achieved near black belt status in it but I don't recall anything being written about the methods used to strengthen the join once it's been welded.

Noel

[Old Rider]

Much has been written here over the years on plastic welding and some of our members have achieved near black belt status in it but I don't recall anything being written about the methods used to strengthen the join once it's been welded.

Noel

I have tried this method :
https://www.youtube.com/watch?v=gRCMIDILfEI

But my experience is that it just cracks open again on the
old brittle plastic on the FJ . I use to make a reinforcement with epoxy putty on the backside after first welded and
scratched the surface .

[ZOA NOM]

That's the beauty of Plastifix. It replaces the plastic and chemically bonds it. It's as strong as new.

[Waiex191]

My lower fairing has one of the parts cracked off at the aft mount bolt and is only held on by the heat shield.  I was going to fiberglass it on the inside.

[ZOA NOM]

My lower fairing has one of the parts cracked off at the aft mount bolt and is only held on by the heat shield.  I was going to fiberglass it on the inside.

Definitely investigate PlastiFix

[fj1289]

Didn't I see something a good while back about paper clips bent and used with a large soldering iron?  A DIY version of Fred's incredible garage sale find?  Seems the imbedded metal would be a good reinforcement.

[red]

Much has been written here over the years on plastic welding and some of our members have achieved near black belt status in it but I don't recall anything being written about the methods used to strengthen the join once it's been welded.
Noel

Noel,

Wire screen-door screening material is good, too; just make sure it's really metal screening (a sample does not burn).  Bend as needed and trim to a good fit with tinsnips or heavy scissors, so there is no metal coming out of the patched area.  You can tack the screen patch into place with a hot soldering iron, of course.
.

[aviationfred]

Plastex/Plastifix can't be beat for the simplicity of use and the ability to actually form missing parts. https://www.aerostich.com/plastex-repair-kit.html?___SID=U

I still have good luck with the old tried and true Black ABS cement. I had a broken tab on the rear seat cowling for my VFR. I mixed the ABS cement with loose fiberglass fibers. This has held fast with no signs of failing.

As Chris mentions.... the Hot stapler machine is a game changer. When I had to make main fairing repairs after the attempted theft of my 95. The fairing was presentable with about an hours worth of work.

1st photo is the VFR cowling tab
2nd photo is the inner side VFR tab, ugly but functional
3nd photo is the Main fairing damage
4rd photo are the Hot staples
5th is the finished repair.
6th photo is enlarged from a 10 foot away shot.

Fred

[Bones]

On one of my chin fairings I used a soldering iron to weld the joints together, then cut a piece out of an old spare I have and using the soldering iron welded the two pieces together. The place where it cracked is now twice the thickness and so far on last inspection is still holding up.

[X-Ray]

As previously mentioned, I have used Plastex on some horrible breaks, and it really does work. Have not had a repair break yet as it actually fuses to the original ABS material

[JMR]

That's the beauty of Plastifix. It replaces the plastic and chemically bonds it. It's as strong as new.

It is a great product. Not cheap but I have repaired many plastic parts with it.

[Millietant]

I love that kit that Fred uses - I used a paper clip, held in needle nosed pliers and heated with a gas torch, to strengthen the joint where I re-attached the piece of my belly pan that got damaged cornering at the Nurburgring many years ago. It was fiddly but so far seems to holding up really well.

I've just read about a plastic welding kit which was used/reviewed in a bike magazine for repairing bike plastics. They gave it a 10 out of 10 rating  .

[red]

I love that kit that Fred uses - I used a paper clip, held in needle nosed pliers and heated with a gas torch, to strengthen the joint where I re-attached the piece of my belly pan that got damaged cornering at the Nurburgring many years ago. It was fiddly but so far seems to holding up really well.
I've just read about a plastic welding kit which was used/reviewed in a bike magazine for repairing bike plastics. They gave it a 10 out of 10 rating 
http://fjowners.com/gallery/12/6213_10_12_20_9_51_23.jpeg

Millietant,

Kinda pricey at US$104 (at the exchange rate on this date), but I'd like to hear if anybody uses it, and for what item, and the results.

The kit is a butane torch with plastic welding rods, for four different flavors of plastic (including ABS).  A local source of more ABS welding rods would be good, here.
I have no pressing need for the kit right now, but it's got a bookmark here.  Thanks for the tip.

https://www.machinemart.co.uk/p/power-tec-plastic-welding-kit-92418/
.

[giantkiller]

I've used plastex many times. Have had no failures so far. Comes with molding bars. Can be reused. Can buy individual components from the company.
Here is a  scoop that was missing the entire coner. Took a mold from a good  piece. Molded in new piece. Put  fine fiberglass cloth on the back. Put  plastex powder on the  fiberglass and  whet with solution. Fiberglass embedded plastic. Sand primer. Done. SUPER EASY.

[Charlie-brm]

Much has been written here over the years on plastic welding and some of our members have achieved near black belt status in it but I don't recall anything being written about the methods used to strengthen the join once it's been welded.

Noel

I have tried this method :
https://www.youtube.com/watch?v=gRCMIDILfEI

But my experience is that it just cracks open again on the
old brittle plastic on the FJ . I use to make a reinforcement with epoxy putty on the backside after first welded and
scratched the surface .

I've seen that lad before but on this one I had to stop watching within a minute. If he thinks a dollar store paint tray is 1/ injection molded and 2/ nylon based, I'm out of here.