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Forum topic by davemw429 posted 04-14-2021 11:32 AM 367 views 0 times favorited 14 replies Add to Favorites Watch
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davemw429

3 posts in 29 days


04-14-2021 11:32 AM

Topic tags/keywords: oil hvlp

I could use some feedback on a finishing problem. I have used my Fuji HVLP successfully many times with latex, and clear coats. First time working with Rustoleum Oil-based gloss enamel, smoke gray. Thinned with mineral spirits as directed, and laid first coat on oak cabinets primed with Bin shellac primer. See pic- paint does not even out over grain… leaves what I’d call surface tension pits. I had no intention of a gain-filled, smooth surface, but assumed the paint would cover and fill the grain better… it’s almost like it was not adhering well to the primer. I tried again using a less dilute paint mixture and same result. Is there a problem going over BIN primer? Or just need multiple coats to fill? Thanks for any feedback!


14 replies so far

View xedos's profile

xedos

285 posts in 382 days


#1 posted 04-14-2021 10:44 PM

Looks like a great job.

If you want the grain filled, you need to fill it with a filler. Paint/primer , especially BIN , is not a filler.

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splintergroup

5122 posts in 2304 days


#2 posted 04-14-2021 10:54 PM

I agree with your “surface tension pits” assessment. Happens with many finishes.

Grain filler is the solution, for a painted top coat I’d suggest a “high build” primer as an efficient way to plug up the grain holes (Oak I assume?)

A topcoat of BIN or other sealer/primer could then be used if needed before the topcoat.

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xedos

285 posts in 382 days


#3 posted 04-14-2021 11:12 PM

high build , high solids primers are better , but are still no solution for filling grain or pores.

You still need a filler for that , and it gets labor and time consuming.

If you want smooth painted finishes, don’t use oak .

View tomsteve's profile

tomsteve

1162 posts in 2300 days


#4 posted 04-15-2021 09:52 AM

what you could do is let the clear fill the grain. sand it all back down and spray 2-3 more coats unthinned. if its still doing the same, sand it down again.
i encourage you to get away from rustoleum products.

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davemw429

3 posts in 29 days


#5 posted 04-15-2021 11:12 AM

Thanks all for the feedback. Many helpful comments. For the record, I wasn’t going for a smooth finish- I was fine with a very grain textured look/feel. I guess I was stumped that the paint was not even getting into the pores, almost like it was pooling only on the uppermost surface. That said, I did try out a few sections where I sanded down, applied 2 more coats of primer. I even tried another panel with an acrylic primer. Then I tried spraying straight from the can (no thinning) as well as various levels of thinned paint. I NEVER got smooth coverage in any of these scenarios. Notwithstanding some user error on my part, I think I am done with oil forever :)

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xedos

285 posts in 382 days


#6 posted 04-15-2021 12:27 PM

You’re not listening, or are simply choosing to ignore the basic facts.

The pores in the red oak need to be FILLED with filler and sanded smooth if you want a flat, even coating. It’s got nothing to do with, rustoleum, oil based, water based ect…... The indented pores are simply messing with the surface tension of the coating you’re applying. Until those are filled either with filler or paint, you’re going to see the condition you have now.

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Fred Hargis

6986 posts in 3575 days


#7 posted 04-15-2021 12:30 PM

Maybe since you have the paint in hand, do the same process on a scrap piece of something, MDF would be good. You can choose to give up on oil paints, but in many cases they are the best choice for some applications.

-- Our village hasn't lost it's idiot, he was elected to congress.

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CaptainKlutz

4446 posts in 2576 days


#8 posted 04-15-2021 12:33 PM

Welcome to Lumberjocks!

IME: Rustoleum oil based enamel is one of the most frustrating materials to spray!

- Is very temperature sensitive.
Will not lay down properly above 90° ambient temp. Cure time quadruples below 70°.

- Portion of solvent flashes quickly in low humidity regions. Always have to thin 10-20%. During low RH and high temp in sunny Arizona, I use 15% acetone and 5-10% PGMEA retarder to prevent orange peel.

- Don’t use MS to thin Rustoleum for spraying. Use Acetone as listed on the TDS by mfg. Acetone has lower surface tension and will flow better than MS also. MS will also increase cure time.

- Very slow cure.
It takes several weeks to fully harden and cure. The thicker the film build, the longer it takes.
I always use enamel harder with Rustoleum or any brand oil based enamel.
There are many different brands, all have same ingredient. Majik brand is usually stocked by Tractor Supply or Farm & Fleet stores. Krylon sells one too. Restoration shop Wet Look enamel hardener is same.
All have same mix ratio 1 part hardener to 16 parts paint. Follow directions, mix it in, and wait Post life is 6+ hours for me in 90° day.

- If you want a smooth surface, base coat must be smooth. Enamel has high natural surface tension, and does not spray well on textured surfaces. You can spray textures, but you need to lay down higher film build, and likely have issues with runs on vertical surfaces.

Personally would never use oil based enamel on wood cabinets.
There are many other better options. If you are willing to use solvent, visit a Sherwin Williams Industrial distributor and use pre-cat pigmented lacquer or pigmented conversion varnish. They can custom mix many colors, and much easier to spray than enamel.

Your location is not in your profile, but can also visit the ML Campbell or Chemcraft websites and look for local distributor for wood coatings.

While BIN primer is OK, it does not sand well. Your local wood coatings distributor will also have cheaper and easier to sand, seal coats for cabinets too.

You spent good money on nice HVLP. Stop buying big box store finishes and use better quality finishes designed for spraying on wood cabinets or furniture. Your finishing skills will triple once you start using commercial grade materials, and reserve the BORG for lawn and garden stuff.

Best Luck!

-- If it wasn't for bad luck, I wouldn't have no luck at all, Doom, despair, agony on me… - Albert King - Born Under a Bad Sign released 1967

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davemw429

3 posts in 29 days


#9 posted 04-15-2021 02:13 PM

Thanks all- REALLY appreciate everyone’s feedback, comments and advice- all useful.

View Rich Voytek's profile

Rich Voytek

2 posts in 28 days


#10 posted 04-15-2021 06:13 PM

If your simply painting, as one of the previous post stated, get away from oil products altogether. Today’s latex products are more durable than in the past. Use a 2mil tip on your gun for the paint. Thin the paint slightly. If you want a clear coat; Varathane polyurethane is a nice product. Sand to 400 grt. between coats.

-- Rich Voytek

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xedos

285 posts in 382 days


#11 posted 04-16-2021 08:42 PM

CK – a wealth of knowledge and advice , as usual.

Why do say BIN doesn’t sand well? My experience has been that it sands very well and behaves pretty much like KemAqua Surfacer in that regard. Now, I am referring to real BIN with shellac not their new waterbased crap. That , does not sand worth a darn.

View CaptainKlutz's profile

CaptainKlutz

4446 posts in 2576 days


#12 posted 04-16-2021 10:16 PM

Why do say BIN doesn’t sand well? My experience has been that it sands very well and behaves pretty much like KemAqua Surfacer in that regard. Now, I am referring to real BIN with shellac not their new waterbased crap. That , does not sand worth a darn. – xedos
Ability to sand BIN depends on thickness. If you brush it on, with heavy coat including runs, it takes much longer to dry than advertised. If you rush dry time, it clogs paper instantly. Shellac tends to glaze sand paper, even with stearate coating to reduce adhesion of dust. I find newer vinyl based primers (like your KemAqua), don’t glaze paper as quickly.

TBH – Don’t recommend shellac BIN as primer, except under latex wall paint. It is not good under any paint in humid/wet environment. They make oil based BIN primer for sealing under enamels. It’s likely the OP’s use of shellac BIN and solvent differences is contributing to the surface tension with Rustoleum, and lack of self leveling.

YMMV

-- If it wasn't for bad luck, I wouldn't have no luck at all, Doom, despair, agony on me… - Albert King - Born Under a Bad Sign released 1967

View xedos's profile

xedos

285 posts in 382 days


#13 posted 04-17-2021 12:39 PM

I guess my sanding setup is optimized for BIN then, as I get great mileage. Not that I use it all that much though.

With mesh abrasives and a sander attached to a vac I see little or no difference between BiN or KA surfacer.

Not what I use as a matter of course in the shop, I just don’t rule out using it . I think it’s a fine product for a hobbyist, homeowner or even a pro in a pinch because it’s available just about everywhere , today, right now. Can’t say the same for the industrial coatings.

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cracknpop

511 posts in 3430 days


#14 posted 04-18-2021 02:04 AM

Did you spray the BIN shellac primer?
My experience is that regardless of product, a spray gun will not get paint into the deeper grain of oak. You don’t really notice it when spraying clears over stain. But I refuse to spray color, especially lighter colors, over oak.

-- Rick - I know I am not perfect, but I will keep pressing on toward the goal of becoming all I am called to be.

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