Undercoating Question

[AltBantam]

Quick question or two. Do I need to coat the bottom of the glassed floor with a fiberglass specific primer before coating with an undercoating? Or can I or is there an undercoating that can be laid atop fiberglass without a primer first? I don't want waste a couple of cans of undercoating just to end up with a mess. Thanks.

 

[Spanky]

I applied truck-bed liner material directly to my fiberglass resin-coated plywood floor with no difficulty. Still in place after 8 years with no signs of lifting.

 

[fletcherson]

No offense, but I can’t imagine a benefit to undercoating it. It’s nasty stuff to deal with when working on the car, it’s miserable to get rid of if you decide to change... from my perspective there are much better alternatives. Truck bed coating or just durable enamel or urethane paint. Undercoating does offer some sound insulation, but it’s intended for rust and corrosion resistance, not applicable to a fair weather fiberglass/wood car.

 

[AltBantam]

Thanks Spanky. Sorry, flecherson, I should have been clearer here. I was planning to use a truck bed liner coating as I posted on another post here. The rubberized coating is to add a little more protection underneath and behind the passenger compartment than painted glass with just paint. Paint is fine in most applications, it's just for my own peace of mind.

 

[HenrysT]

clean the surface with acetone and a light scuff with some #120

 

[fletcherson]

Thanks Spanky. Sorry, flecherson, I should have been clearer here. I was planning to use a truck bed liner coating as I posted on another post here. The rubberized coating is to add a little more protection underneath and behind the passenger compartment than painted glass with just paint. Paint is fine in most applications, it's just for my own peace of mind.

Just my perspective, it’s your car! Anyways if you didn’t know, there are also coatings designed for abrasive areas like rocker panels and lower quarter panels. It was used by auto manufacturers and should still be available at auto paint suppliers. It’s paintable, so other than the texture from its thickness, is aesthetically pleasing and is rigid so it won’t dissolve from oil or the like and is sandable if needed at a later date. Sorry, the product name escapes me.

 

[Spanky]

I think it's just called Rocker Panel Coating and 3M sells it; comes in colors, too (I think?)

 

[AltBantam]

Originally, I bought rust-oleum bed liner in a spray. I have used rust-oleum paints on many different projects. Never had a problem. This stuff did not work at all. It coated but not very well, even though is "should" coat anything. Bought Raptor roll-on bed liner next, worked like a charm. Photo on my build page. It's messy rolling it on, but it gave me the look I was looking for.

 

[Muscle Inkk]

I've used the Herculiner from Advance Auto on a few stunt bike tanks and it held up really well even with gas being spilled in it.

Don't know how it compares price wise.... It's worth looking at though.