Plastic bits

[Alte Fahrt]

 When I did my tear down the fairing had cracks and breaks. I tried repairing it with a special epoxy type cement made for ABS. Some places are still holding but others have failed. I've looked on Ebay for a replacement but they all seem to have the same problems. I read about the Lego and other repair methods and may give them a try. It would be easy enough to pull it off and make a mold of it from fiberglass. I could then make a new one from fiberglass with metal reinforcements at the stress points. Another option is I know a guy that does carbon fiber work. I know that ABS was used on account of the vibrations but to me it obvious the design failed if they all break in the same place. Anyone  have any thoughts about fiberglass or carbon fiber?

[cclase]

I've had good success with Lego ABS "goop" for fixing cracks and even fabbed up a new side scoop tab with it.  It seems to hold up well.  Depending on how much acetone you use, it can have the consistency of a spreadable sticky goop or as think as a moldable putty.  That said, the repairs I've made weren't to fix major issues...not sure if you had a chance to see this yet, but here is an excellent link on paper clip welding which seems like it would be a great method if you got some real damage:
http://www.fjowners.com/index.php?topic=12310.0
Regarding fiberglass, I've contacted Dutch with Airtech-Streamlining (http://www.airtech-streamlining.com) to see what they can do for the FJ.  He told me that he's interested but I hit him at the beginning of their busy season, so he asked I get back with him towards the end of summer.  They will need a fairing to make a mold from, so I'm not exactly how that will work out.  At any rate, I'll post up if it ends up as a viable solution.  Here is a very interesting link for the DIYer:
http://daproglasscraft.atwebpages.com
Give the Lego goop a shot...it's cheap and effective.  Good luck!

Chris

[FJmonkey]

I use a combination of ABS putty and ABS welding. I recently rebuilt my front turn signal mount tab.
http://www.fjowners.com/index.php?topic=15362.msg155165#msg155165

And before that the side scoop mount tabs and front fender tabs.
http://www.fjowners.com/index.php?topic=14653.msg148209#msg148209

[Charlie-brm]

Maybe the opinion of a cranky old guy, but working with fiberglass for essentially a one off production is a real pain. Especially so if you are new to the whole process.
I used to help fellow paddlers as we took turns making our white water kayaks and canoes. That was with an established, refined mold that was being passed around for years amongst the members of several clubs. In other words, the difficult master mold stage was already done for us. We just had to lay in the glass, usually without gel coat which adds weight and doesn't like rocks. It was still dirty, messy work though we loved doing it for the excitement of making another water craft. I still get butterflies when I smell fiberglass resin. (and the smell of wintergreen, but that's another story)

Following that I prototyped some fiberglass racing paddles with an injected foam resin core in two styles, curved & quick and the big flat water mover. It seemed we took forever to get the plugs to perfection. Then as those good instructions on the link mention, you figure out your parting lines and get them dead on or it shows on every part you make and it takes up filing and sanding time on the parts to correct. The female mold halves ending up being over a half inch thick of resin and glass. Darnn heavy even for something the size of a paddle blade. They need to be very rigid or your product could have permanent warps or distortions that will mess up lining up the edges to other pieces.

On the positive side, if one perseveres and gets the mold right, that's the most difficult part done. If the intention is not to make additional sets for sale, the molds might be loaned out to other enthusiasts to lay up their own sets. Caveat: The boat mold loans came with the rights from the boat designer. If I were to copy my original Yamaha FJ parts, I wouldn't be proclaiming I'll make additional copies or loan out the molds.

Good luck if you go for it.

[Nova]

I'm not sure which product you are using. I've been using PlastiFix for everything from repairing cracked tabs to welding back together large broken off pieces. And I do mean welding, as opposed to gluing or cementing. That's the big difference. Glues tend to always break eventually because they rely on adhesive properties. Something that actually melts the plastic slightly will always form a better bond once the plastic re-cures.

[4everFJ]

ABS cement works by melting the parts together, unlike normal glue.

[FJmonkey]

ABS cement works by melting the parts together, unlike normal glue.

My experience with ABS cement is a brittle bond. It works better based on the amount of surface area. Think of how it was intended to work, pipe fittings, lots of surface area. On the the bike, not so much...

[4everFJ]

ABS cement works by melting the parts together, unlike normal glue.

My experience with ABS cement is a brittle bond. It works better based on the amount of surface area. Think of how it was intended to work, pipe fittings, lots of surface area. On the the bike, not so much...

Sure, but it is very good to hold the pieces together when you plastic weld.

[Nova]

ABS cement works by melting the parts together, unlike normal glue.

My experience with ABS cement is a brittle bond. It works better based on the amount of surface area. Think of how it was intended to work, pipe fittings, lots of surface area. On the the bike, not so much...

That actually make a good deal of sense. If it is the cement for ABS plastic pipe it's not really expected to deal with a lot of flexing or vibration. Products like PlastiFix are formulated with an automotive environment in mind.

[giantkiller]

I use plastex comes with reusable molding bar. Haven't had a repair fail yet. Can be sanded. Good stuff I did a write up on it.I With pictures. If I knew how to post a link. I would. It was called scoop repair with plastex.

[rktmanfj]

I use plastex comes with reusable molding bar. Haven't had a repair fail yet. Can be sanded. Good stuff I did a write up on it.I With pictures. If I knew how to post a link. I would. It was called scoop repair with plastex.

http://www.fjowners.com/index.php?topic=13169.0

[giantkiller]

Thanks Randy