TY250A Seat Base Questions

[mr neutron]

Hey, All!

I'm slowly getting work done on my project TY250A. I got the swingarm "repaired", sandblasted, primered and shot some rattle can enamel on it today. The old "bumps" on the the swingarm that the snail chain adjusters push off of were really worn with grooves somehow. Maybe someone (previous owner) let the rear axle get loose? I say this because there is also damage to the dust collar on the drive side of the sprocket and the inside of the swingarm itself. I dunno how it could've happened, but it did. I ground off the old bumps, and drilled and tapped for 6mm allen headed bolts for the adjusters to work from:

 

Now, I'm working on my fiberglass seat base. I made new brackets for the seat's rear mount before I found out that Feked sells them.  Now, I'm sanding off the yellow flaking paint the PO put on, as well as some of the original yellow, down to the bare 'glass. My questions are:

Does painting fiberglass actually require any "special" type of primer and paint? I'd really like to just put on some paint I can easily/inexpensively buy for now, and can use for future repairs. Something like a rattle can primer with rattle can hi-gloss enamel over that? I don't really want to shoot, say, colored gel coat on, or some of the more pricey marine products. Sorry for what's probably a stupid question. I suppose I need to say that I want this bike to be something I ride and crash, not a restoration showpiece. It's been 40+ years since I've done any bodywork involving fiberglass, and while I don't recall doing anything special while putting on and glassing in some fiberglass fender flares for my old Datsun 510, I would suppose there's been some improvements in chemicals for painting fiberglass by now........

Thanks for your help here,

Jimmie

[RonH]

You’re not gong to like my answer but here it is anyway. Yes, painting fiberglass requires a specialized bonding primer and high-quality exterior or marine-grade paint to prevent peeling and ensure proper adhesion. Because fiberglass is smooth and non-porous, standard paints and primers will not bond to it without the proper chemical or physical base.

Use a two-part (2K) epoxy primer or a dedicated bonding primer obviously after sanding and cleaning.

 

Use a marine-grade polyurethane or acrylic enamel paint.

 

[mr neutron]

Thanks, RonH!!

I'm grateful for your reply here. 

 

9 hours ago, RonH said:

You’re not gong to like my answer but here it is anyway. Yes, painting fiberglass requires a specialized bonding primer and high-quality exterior or marine-grade paint to prevent peeling and ensure proper adhesion. Because fiberglass is smooth and non-porous, standard paints and primers will not bond to it without the proper chemical or physical base.

 

Use a two-part (2K) epoxy primer or a dedicated bonding primer obviously after sanding and cleaning.

 

 

Use a marine-grade polyurethane or acrylic enamel paint.

 

 

Yeah, that was not the answer I was hoping for, but it kinda confirms 1): stuff I've been reading online, and watching in videos, and 2): it kinda explains why the paint put on by the previous owner is flakier than all git out.

I don't know if you're located in the U.S. as I am, or if you're familiar with Rustoleum brand paints like their inexpensive line of rattle cans and quarts called "Stops Rust" Gloss Protective Enamel. I've had really good luck with this paint on metal (like the swingarm) & wood whether from a rattle can, or stuff I mix up with acetone and Valspar hardener and shoot from a spray gun. It's cheap, easy to come by for me, and fairly durable. But I *think* it's basically just an ordinary oil-based enamel, and probably not the acrylic enamel that you recommended?

FWIW, here's a pic of what I've done so far, regarding prep. I've sanded what I consider "the hard parts" (has all the intricate curves and such) of the fibeglass base with 120 grit. I know that I want all that flaking paint off, and figured I may as well take it the mostly bare fiberglass while I'm doing it. I just hope I can follow the contours well enough of the parts of the base not covered by the seat. I also found a couple of cracks, and some chips in this base I'll need to repair before priming. For some reason, the entire part I've sanded, and some I haven't had a thick layer of silver silicone seal over all of it that the seat covered.    It clogs my 120 grit sandpaper up like crazy, and doesn't make this kinda tedious job a bit more difficult.

Again, many thanks for your advice and help here, RonH!!

Edited 13 hours ago by mr neutron
corrected spelling errors