Wlll epoxy mixed 1:1:1 as a sealer fill 400 scratches?

jtfx6552

Member
Or do I need to wet sand with 600?

I'm sanding some single stage urethane I need to redo, is using the sealer a good plan, will it enhance adhesion? Or should I just wet sand with 600 and add another coat of the SS color?
 
If you haven't had to do any bondo work you should be fine just respraying with SS provided you also haven't cut through past the SS.
 
I don't think we would ever seal a recent respray like that unless there were many serious issues, single stage makes a great substrate for itself in most cases.
 
I'm resurrecting this old thread as I also want this exact answer. Will SPI epoxy mixed 1:1:1 as a sealer fill 400 grit sand scratches?
I'm sanding down 3 week old SPI epoxy and will seal then paint.
Thanks
Danford1
 
danford1;n82733 said:
I'm resurrecting this old thread as I also want this exact answer. Will SPI epoxy mixed 1:1:1 as a sealer fill 400 grit sand scratches?
I'm sanding down 3 week old SPI epoxy and will seal then paint.
Thanks
Danford1

400 velcro on a DA with interface pad, it may.

400 by hand I think you will see your sanding strokes. This is ASSuming you're painting a solid color and not metallic.
 
The scratches that show through should be ok if it is a solid color. If its metallic I would finish with 600. 1:1:50% is not going to really cover.
 
It will be metallic. I'll get it smoother so the sanding scratches don't show though.
Thanks
Danford1
 
Dan, Since this thread I tried epoxy mixed as a sealer per the perfect paint job "double shot glass of SPI #885 Urethane Reducer per quart" and I liked the results better. Laid absolutely flat, but covered much better.
 
That's what? 3oz per 32oz? 16oz-16oz-3oz doesn't seem close to the recommended 1:1:1. So what IS the SPI recommended mix for a sealer?
 
Try 1:1:25% or expressed another way 1:1:1/2. I spray it at 1:1:10% and it lays down nice for me but some here think its to hard to spray at that reduction. 1:1:1/2 should flow out nice and cover better than 1:1:1
 
1:1:1 is only recommended as the maximum reduction for the maximum drying speed. The only official best practice that I know of is found in the Perfect Paint Job tutorial, and equates to 1:1:10%. I like to use 30%, because it nicely balances film build and dry time.

There is no true recommended reduction, as far as I know.
 
Ok so if I mixed 1:1:30% and I wanted about a half a gallon sprayable, then I would mix 28 oz part A 28 oz part B then 8.4 oz of reducer. Is that correct?

Danford1
 
danford1;n82747 said:
Ok so if I mixed 1:1:30% and I wanted about a half a gallon sprayable, then I would mix 28 oz part A 28 oz part B then 8.4 oz of reducer. Is that correct?

Danford1

That's my understanding, but I'm looking forward to what the experts say.
 
jtfx6552;n82748 said:
That's my understanding, but I'm looking forward to what the experts say.

56 (.3)= 16.8, 30% of 56oz is 16.8oz.

I'm no expert but 8.4 looks like 15% reduction to me.
 
danford1;n82747 said:
Ok so if I mixed 1:1:30% and I wanted about a half a gallon sprayable, then I would mix 28 oz part A 28 oz part B then 8.4 oz of reducer. Is that correct?

Danford1

28+28=56, 0.3*56=16.8, so roughly 17oz reducer into 56oz RTS epoxy is a 30% reduction.

The percentage of reduction is calculated from the volume of ready to spray product!

More commonly for a fuller bodied sealer would be 25%, which would be 28+28=56, 56*0.25=14, so 14oz added to 56oz RTS epoxy is a 25% reduction.

We can also see that 1:1:1 is the same as 1:1:50%:

28+28=56, 0.5*56=28, so 28oz reducer into 56oz RTS product is a 50% reduction.
 
WOW that is some serious math :), I would say get a measuring stick or a glass mixing beaker and do it that way, much faster and no screw-ups.
 
Thank you guys for clearing that up. That is exactly the info I wanted.
I'll make note of it.

Danford1
 
DATEC;n82752 said:
WOW that is some serious math :), I would say get a measuring stick or a glass mixing beaker and do it that way, much faster and no screw-ups.
Sorry if I made it look more complicated than it really is, but the fact is that without an understanding of arithmetic, the lines on the cup or stick might not be helpful.
 
crashtech;n82768 said:
Sorry if I made it look more complicated than it really is, but the fact is that without an understanding of arithmetic, the lines on the cup or stick might not be helpful.

You are certainly right Crash, I've had to educate more guys than I remember in fractions and ratios. Sad and kinda scary to think there are so many people with such a poor basic math understanding.
 
IMO, there is too much dependency on calculators today. I've seen young people not able to do simple math at cash registers. At Home Depot recently I bought four 24" pieces of wood trim sold by the foot and the gal at the register had problems working the math in her head for total length.
I remember back when hand held size calculators were just starting to become common (and affordable) in the early 70's my teacher in school refused to allow them. Instead, we did scientific calculations and large numbers with a slide ruler and the powers of 10. Funny now that method is considered museum material though I still use powers of 10 today to work large numbers: http://www.hpmuseum.org/srinst.htm
As an old WW2 vet friend once said: "yep...those were the days when men were men...and the sheep knew it"

Mike
 
Back
Top