OK. So I've got some plastic repairs to do on the turbo bike. Thought I would show a little bit on plastex repairs. Not real good with pics but hopefully you'll get the idea.
First you need to groove out the back of any cracks. I use a dremel tool with a small ball shape
(http://fjowners.com/gallery/8/2349_20_01_15_3_57_00_9.jpeg)
Then fill the cracks with the plastic powder from the kit
(http://www.fjowners.com/index.php?action-gallery;sa=view;id=8418)
Then use the liquid to melt the powder and let it sit for an hour or so and crack is repaired.
(http://fjowners.com/gallery/8/2349_20_01_15_3_56_55_7.jpeg)
Then if you want to reinforce it. Sand the area a little to make sure its clean and to rough it up a little.
Then cut some fiberglass cloth to the shape of what you want to reinforce. ( put packing tape on one side of the fg cloth before you cut to shape). Then cover the entire piece of fg cloth with plastic powder. Then wet the powder with the liquid. And place the piece over the repair. Use the tape to smooth out any air bubbles. The tape adhesive will let go after the liquid melts it. After an hour or so take the tape off and trim it up. Cracks are repaired and reinforced with fiberglass
(http://fjowners.com/gallery/8/2349_20_01_15_3_56_50_5.jpeg)
(http://fjowners.com/gallery/8/2349_20_01_15_3_56_36_0.jpeg)
OK I did that to fix the scoop I was going to take a mold off of. To fill the chunk that was missing from the scoop I'm using on the turbo bike. I forgot to take a pic of the scoop with the chunk missing but if you look every thing that is black when I get done was missing.
First clean everything up with grease and wax remover. Them sand entire area that you will be repairing alittle. To clear an rough it up.
Then melt the reusable molding bar comes in the kit (will have to buy a couple more bars if you are making a big repair. This is 3 bars melted together). And take mold off good piece. Wait for it the completely cool. I tried to take it off too soon and caused and imperfection. I'll have to fill with plastex and sand down.
Tape the mold securely to the piece to be fixed. Fill it with powder and wet it all down with the liquid. You can add more powder and liquid to fill any settling. Then wait a couple of hours. Again I got in a hurry and caused some things I'll have to fix.because I tried to remove the mold before it completely set up.
(http://fjowners.com/gallery/8/2349_20_01_15_3_56_47_4.jpeg)
(http://fjowners.com/gallery/8/2349_20_01_15_3_56_44_3.jpeg)
(http://fjowners.com/gallery/8/2349_20_01_15_3_56_39_1.jpeg)
I fixed the cracks in the piece that had the chunk out at the same time I filled the mold. And also reinforced it with fiberglass latter. Just like the first piece.
I will sand the plastex smooth and fill any inperfections with plastex and sand again. And paint
If it's just cracked you can repair it from the back with plastex. Like I did with the first piece. And leave the original finish. Oh yah I forgot. Put packing tape on the paint side to prevent the plastex from bleeding through from the back. When just repairing cracks. When you don't want to repaint
I bought a Plastex kit a few years back, and have been very happy with its performance. I used that moldable black plastic block that you show, to re-create missing pegs on the side covers, and front fender tabs too.
Thanks for posting your results with it.