Recommendations for a sandable primer.

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terryg

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I have tried Rust-Oleum 2x primer but is has an almost rubberlike consistency and does not sand well. Rust-Oleum spray paint availability has been all over the board recently.
 
I have tried Rust-Oleum 2x primer but is has an almost rubberlike consistency and does not sand well. Rust-Oleum spray paint availability has been all over the board recently.
Rustoleum filler & sandable , automotive. It's pretty much all I use now. I typically buy it at Walmart.

I have used the Rustoleum 2X, it's not nearly as good, IMO. It goes on like semigloss paint, and loads up the sandpaper.

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I really like the "automotive grade" primer filler... It's rustoleum brand though. I've never had availability problems with it. Saw it in a couple of stores last week in fact.
Ken
 
I've found that a little talcum powder (the real stuff, I haven't tried cornstarch) applied periodically to the rocket minimizes the clumping and clogging of sandpaper that occurs with some "sandable" primers.
 
Rusto grey regular primer doesn't seem to dry. Even after several days. I stopped using it. I have tried the white. It dries faster and sands ok. Runs a lot on me. The Automotive primers I have used. The black is real bad. Grey is ok and the redish has given me good results. The filler primers I used a few years ago. As I remember I had results similar to the regular grey. That is IIRC. Lately my memory has not been good.
 
For a white primer I use this stuff. I get it at Home Depot. Use it after a high-build grey. For sanding any primer, especially the high-build type you need to make sure it is fully dry. May take days if applied heavy.
 

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I prefer just the Filler/Primer instead of the "Sandable" Filler/Primer -- the sandable stuff was always too gritty for me.

Wow -- prices have gone up... For a little while you could get it cheaper at Harbor Freight than at HD/Lowes but now it seems expensive everywhere...
 
I prefer just the Filler/Primer instead of the "Sandable" Filler/Primer -- the sandable stuff was always too gritty for me.

Wow -- prices have gone up... For a little while you could get it cheaper at Harbor Freight than at HD/Lowes but now it seems expensive everywhere...

Gritty... agreed. But that's pretty typical of a sandable primer. It doesn't go on super smooth, it's meant to be a high build that gets sanded.

But with minimal sanding, and I mean just a 320 grit once over, that primer grit is gone, and you are left with a great base for the paint.
 
I use, and can recommend, Dupli-Color Sandable Primer that I purchase at a local auto parts store (O'Reilly in my area). It is user friendly and sands well. Available in various colors although I have used only the grey primer.

Mel
 
Addressing a previous post, the Dupli-Color sandable primer is available in white.

Mel
 
So, I used Rusto grey automotive sandable primer and works fine. I sanded the first coat. I have 3D printed plastic parts. I painted again. I wondering if I should skip the sanding and go to straight to the regular spray paint.
 
I use Krylon gray filler primer for the first two coats, sanding each down to the white tube. That fills spirals and tube joints. I follow that with a coat of Krylon white sandable. Both sand easily. And my top coats look great. I think what was Filler Primer is now 2-in-1 High Build.
 
Great thread, as I too have had little luck with the 2x Rustoleum primer stuff you can get at Walmart. I mean, it works, but like others have said, it doesn't seem to dry and feels a little sticky/rubbery despite letting it dry for several days (even when exposed to 85 degree air with 25% humidity that's being flown onto it).

I'll definitely look into the Krylon or fillable primer Rustoleum alternatives...
 
I use Krylon gray filler primer for the first two coats, sanding each down to the white tube. That fills spirals and tube joints. I follow that with a coat of Krylon white sandable. Both sand easily. And my top coats look great. I think what was Filler Primer is now 2-in-1 High Build.

Do you have a link to that product...or at least a picture of what the can looks like?
 
Do you have a link to that product...or at least a picture of what the can looks like?
I bought two cans from Amazon a year ago for $.99 each. It's now $19.80 each. (!!!)
https://www.amazon.com/gp/product/B087XB839F
I found this on Walmart's website for $6.47. I think it's the same stuff, rebranded 2-in-1 High Build primer.
https://www.walmart.com/ip/Krylon-A...-Primer-Spray-Paint-Flat-Gray-12-oz/897415503
I haven't used 2-in-1 yet, but will be picking up a couple of cans this afternoon. But I won't be using it for at least a month, since it's too hot to paint right now. As @teepot mentioned above, Krylon primer has a relatively narrow temperature application window for desert dwellers.

FWIW, this stuff is bone dry in a few hours. No rubbery feel when sanding, as others have reported with some Rustoleum primers.
 
I bought two cans from Amazon a year ago for $.99 each. It's now $19.80 each. (!!!)
https://www.amazon.com/gp/product/B087XB839F
I found this on Walmart's website for $6.47. I think it's the same stuff, rebranded 2-in-1 High Build primer.
https://www.walmart.com/ip/Krylon-A...-Primer-Spray-Paint-Flat-Gray-12-oz/897415503
I haven't used 2-in-1 yet, but will be picking up a couple of cans this afternoon. But I won't be using it for at least a month, since it's too hot to paint right now. As @teepot mentioned above, Krylon primer has a relatively narrow temperature application window for desert dwellers.

FWIW, this stuff is bone dry in a few hours. No rubbery feel when sanding, as others have reported with some Rustoleum primers.
Thanks!
 
I bought two cans from Amazon a year ago for $.99 each. It's now $19.80 each. (!!!)
https://www.amazon.com/gp/product/B087XB839F
I found this on Walmart's website for $6.47. I think it's the same stuff, rebranded 2-in-1 High Build primer.
https://www.walmart.com/ip/Krylon-A...-Primer-Spray-Paint-Flat-Gray-12-oz/897415503
I haven't used 2-in-1 yet, but will be picking up a couple of cans this afternoon. But I won't be using it for at least a month, since it's too hot to paint right now. As @teepot mentioned above, Krylon primer has a relatively narrow temperature application window for desert dwellers.

FWIW, this stuff is bone dry in a few hours. No rubbery feel when sanding, as others have reported with some Rustoleum primers.
Here you are. I agree it dries fast and is easy to sand. No clogging the sandpaper. One of these days I'll have to see if that primer plays nice with Rusto colors.
Dane just stay up until 3 or 4am. You can paint then. That's what I have been doing.20220817_192305[4474].jpg
 
Dane just stay up until 3 or 4am. You can paint then. That's what I have been doing.
That's what I've been thinking for a week now. I just have to round up some good lighting. BTW, I picked up two cans of that Krylon 2-in-1 primer at Walmart. I'm hoping it behaves the same way as the filler/primer they used to sell.
 
When I picked up the Krylon gray primer at Walmart, I was going to grab some white sandable while I was there. But they were out. Did a little checking around—Lowes doesn't carry Krylon filler/primer or white sandable anymore, Amazon wants $15 for the white, Menard's has it but wants $12 to ship it. It's like Krylon primers have become a controlled substance! What was $5 primer is now $15 to $20.

I may end up using Duplicolor for the white primer. It's all I can find for a decent price. O'Reilly has it for $10. Never sprayed Duplicolor over Krylon gray primer, and under Krylon gloss. I guess we'll see how that works.

Then again, did someone say Rustoleum 2X sands OK? I guess that would work as well as Duplicolor when it comes to playing nice with Krylon gloss top coats.
 
Then again, did someone say Rustoleum 2X sands OK? I guess that would work as well as Duplicolor when it comes to playing nice with Krylon gloss top coats.
No, it doesn't...or at the very least, many of us have experiences with the 2X primer feeling rubbery or sticky as if it's not 100% dry.

Someone said the 2 in 1 filler/primer from Rustoleum works well, though.
 
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