So just like title says, I'm thinking of painting the underside of my car. It's been blasted already, but I need to run over it with a DA to clean up flash rust. I'm building it as a drag and drive car, so not a daily driver or a show car. I'm not a fan of undercoating or bed liner. I was going to spray it with SPI epoxy, and follow it up with SPI single stage black, then couple coats of universal clear. Really only concerned about protection and a easy surface to clean. Since I'm new/ been away from painting/body work since I was in my 20's, is there any issues or problems with doing this? Thanks for your input.
Painting underside of car.
- Thread starter BretW
- Start date
Dean Jenkins
Promoted Users
Barry talked me into Black Epoxy only for underside and engine compartment.
Haven't regretted it for a minute.
His point was that nothing is more resistant to chemicals or scratches than epoxy.
Here is my underside and engine compartment/underhood, over a year old.
Haven't regretted it for a minute.
His point was that nothing is more resistant to chemicals or scratches than epoxy.
Here is my underside and engine compartment/underhood, over a year old.
If you live in the Midwest (IL) consider moisture cure urethane for better salt corrosion resistance.
Is that just SPI epoxy? Looks good.
It's a 1500 HP 70 Chevelle, will never see snow.
Chris_Hamilton
Trying to be the best me, I can be
Better than epoxy? I don't think so. Ever see what stuff coated in POR-15 looks like after awhile (base metal)? Epoxy (SPI) is the most corrosion resistant refinish product available AFAIK. If he uses epoxy as his base then there is no need for any other product for corrosion resistance.
Chris_Hamilton
Trying to be the best me, I can be
This is a good thread on POR-15 which is a moisture cure urethane.
why you never use POR-15 EVER!!!!
I have been redoing a 30k mile 2000 Dodge Ram 4x4 deisel dually that was bought new. It is a work truck and is used to pull when needed. This is not a show job but is being done as a no holds barred job that hopefully will last longer then the factory and prove to be better then the crap POR-15...
www.spiuserforum.com
MJM
Promoted Users
You shouldn't use Universal Clear on the underside of your street/strip car. If you decide to BC/CC, use Euro or Production Clear. I think you would be happy with a single stage over epoxy.
Chris_Hamilton
Trying to be the best me, I can be
Dean Jenkins
Promoted Users
Yes. As long as it is not exposed to continuous sunlight, it is a good finish coat.
3 coats with about 4 hour induction.
Chris_Hamilton
Trying to be the best me, I can be
SPI black epoxy has UV inhibitors in it. It can tolerate sunlight.
theastronaut
Promoted Users
I don't see any need for clear especially on top of single stage, but wouldn't Universal be more chip resistant since it stays softer than Euro?
I'd shoot three coats of epoxy if it just needs protection and isn't going to be judged in car shows. Shoot the last two coats wet so it flows out, it'll dry to a really nice satin/low gloss sheen that is smooth and cleans up easily.
On show stuff I shoot single stage with flattener to adjust the sheen as preferred.
I'd shoot three coats of epoxy if it just needs protection and isn't going to be judged in car shows. Shoot the last two coats wet so it flows out, it'll dry to a really nice satin/low gloss sheen that is smooth and cleans up easily.
On show stuff I shoot single stage with flattener to adjust the sheen as preferred.
I want the firewall/cowl and area behind the doors to be shiny black, so I figured it wouldn't take much more to spray the bottom of the car while its on the lift. After I put it back on the frame, I'm welding in a 10 point cage, so its not coming back apart anytime soon. I'm gonna finish the body in SPI black BC/CC. I know some will say use single stage for black, but for me being away from painting for so long, I think the bc/cc will be easier to fix any mistakes I make.
Nice looking Chevelle, 68 or 69?
Dean Jenkins
Promoted Users
Thanks! 68 el Camino
SPI BC/CC with Universal Clear.
SPI BC/CC with Universal Clear.
Lizer
Mad Scientist
POR, no. An aluminum pigmented MCU is pretty hard to beat for corrosion resistance. It will absolutely beat epoxy.
Chris_Hamilton
Trying to be the best me, I can be
Is that common in automotive refinish? I've never heard of it being used. And is it necessary? Doesn't epoxy provided all the protection realistically that a vehicle needs? I can see using something like that in a saltwater boat or environment but being that it's not common for refinish tells me there is no need for it. Your opinion?
Treeslayer
Mike
what is MCU?
