First Gen Body Work

[Guest seuadr]

I'm curious, and wonder if any of you have any knowledge on the matter.

 

this 87 blonde is mechanically very sound, but i'm finding more and more bodywork that is cracked, specifically on the right hand side. i think it went down on that side, or may hve dropped from a standstill. it's all cracking to bits, and i'm not sure what years will fit? would bodywork from a mk1 fit a mk2?

 

also, i'm considering going over the inside of all the larger plastic pieces with fiberglass to strengthen it. anyone done that?

[showmebob]

I have a new to me 86 and have found alot of problems with the plastic on it, the trunk had peices missing from the bottem where it bolts down, I have been doing alot of research on the net about ABS plastic, i took peices from another broken saddel bag made of ABS plastic and cut them to fit and welded them in with a sodering iron then back it up with fiber glass mat glued it down with ABS glue, time will tell if this will work, but it seams to be strong enought i think it will.

You can grind up the abs plastic and use asetone to mix with it and make a filler, just do a search on the internet on reparing ABS plastic and read away there is alot of information on there.

Good luck

[6m459]

Hi,

 

Body plastic, the perennial problem for these old tugboats!

 

I have done quite a lot of plastic body panel repairs using fibreglass. I find it is hit or miss whether it sticks well or not. I have some repairs that have lots of miles on them and some that failed quite quickly. Adhesion to the plastic seems to be the issue. On the whole, I have come to the conclusion that it is not the best strategy unless one is building a complete part from scratch as I did with the piece across below the radiator which was missing on my blue bike when I got it.

 

Recently, I have been using, of all things, Mighty Putty for some repairs even to high stress areas like mounting tabs. Seems to behave better than the f/g so far. In many repairs, I have combined the mighty putty with the fibreglass drywall mesh tape for strength reinforcement. I mix a wad of mighty putty about big enough for the repair and then split it in two. I apply the first half and smooth it into place, then appy a piece of the mesh so that both sets of strands go diagonally across the crack I am repairing. I smooth that in till the mighty putty squishes thru the mesh, then I put the other half of the batch of mighty putty over the top of that and smooth it in well.

 

Surface prep seems important for both f/g and m/p adhesion. I clean the OEM body plastic on the back side with Acetone prior to application of the repair material. I sometimes also rough up the area with an exacto knife blade in a criss cross pattern to aid adhesion.

 

http://www.powergate.ca/~bjh/pix/DSC00275-600.jpg

Mounting tab formed of Mighty Putty

 

There is also a 2 component product called PLASTEX that is very good. I have used this to rebuild missing pieces in the black dash panels and have managed some quite intricate repairs. Its also available in various colours.

 

The Plastex kit comes with a 'silly putty' like substance that you heat up and then spread onto a good part to take the shape. This 'silly putty' then retains the shape when it cools down so you can transfer it to the same place on another identical part that has a piece missing. This forms a mold into which you can pour the actual plastex which bonds into the broken part complete with the surface pattern! When the Plastex has cured, you peel off the 'silly putty'. Its really quite amazing, but a bit fiddly and it takes time to develop the technique. I am not sure I can claim to be an expert, but I have achieved some nice repairs none the less.

 

Hope this helps.

 

Brian H.

Edited June 23, 2010 by 6m459

[Sheradan]

I've done many repairs using ABS and epoxy. Works great everytime. Use fiberglass to fix fiberglass.

[bongobobny]

Yah!! 25 year old plastic can deteriorate and it's a comon problem!! I use the 2 part epoxy specifically for plastic, and take a rotory tool and make a groove on the inside surface for more contact area. The plastic epoxy also can fill in voids and can be sanded and shaped...,

[Guest seuadr]

I've done many repairs using ABS and epoxy. Works great everytime. Use fiberglass to fix fiberglass.

i can't afford to slather epoxy all over the back of the spiderwebbed plastic, though

[jimmyenglish]

The 2 part epoxy's work good for some of the small cracks. Contrary to some of the other posts, I've had great results with fiberglass and have been using it on all the bigger cracks. As far as mounting tabs, I've been refabricating them out of steel as in my experience gluing or glassing hasn't held up. Too bad the plastic on these bikes is so brittle. It certainly is frustrating!

[SilvrT]

Did a lot of repairing on my '87 (see one of the pics in my profile). Used the plastic welding method with a soldering gun and a flat tip. Followed that with ABS 2-part epoxy. Worked very well.