Should I just expect orange peel when spray painting?

[mfguitar]

Your Rustoleum finish looks nice! I think I'll use some other scrap I have to give that a test as well.
Maybe I shouldn't have sprayed my paint out in the sun...

And there is at least a partial answer. Direct sun is never good.

 

[JuneauMike]

To sand my current coat smooth, what grit should I use, and should I wet or dry sand it?

Hmm. You know, I think I would mask off those test pieces in a few sections and just experiment. I'd probably go 600 grit wet sand on one (which is where I think I'd start) and use a more aggressive 400 grit wet sand on another panel to see if you can get away with it. Try to find a sanding motion that is repeatable and not something where you are bearing down on the test piece with any real force -- just the sandpaper. I'd probably use a felt pad or some cork and not something hard and unyielding as a backer on the sandpaper (don't use your fingers or your hand, that will give unpredictable results). Wet sanding keeps the sandpaper from clogging so you are getting consistent grit strength during the sanding operation. This is final level sanding.

And just for the fun of it I'd run a stopwatch as well (most smartphones have one). If you burn through the paint take note of the time. The really stressful thing about sanding paint is that I have no idea how thick the paint actually is, and it's never as thick as I'd imagine it is. Keeping even pressure and a stopwatch helps ease that stress for me.

I don't try to avoid orange peel at all. But I dry sand between coats to keep the divots as shallow as possible. Can't remember what I use there but I think I generally use 800 grit between individual thin coats. For some reason, that's my favorite grit of sandpaper. Professionals probably have the confidence to use much more coarse grit paper and not waste so much time.

I'm a novice so take my advice with a grain of salt, but I think I approach this stuff as conservatively as I can. My time is free and it's better to waste my time doing no harm than to rush and ruin what I'm working on. Again, kudos on using test pieces.

 

[Freeman Keller]

To sand my current coat smooth, what grit should I use, and should I wet or dry sand it?

My only experience is with nitro cellulose lacquer and I sand to 320 or 400 dry between sets of three coats. That is enough to remove scratches, orange peel and other flaws and leaves a little tooth for the next coat to melt into. A professional finisher would not have to do any sanding between coats but I'm not a pro.

I reserve wet sanding for after the final coat, again a pro wouldn't need to but I usually start at 800 and go up thru the grits to 2000 before buffing. I have no experience with your products so I could be completely wrong.

 

[CowTownPickers]

Like Dogmeat said, heat the can ! It thins the paint out and you don't get orange peel in your finish. If you don't have a heat gun, boil water and take it off the stove and insert can. I leave mine in the sun in the warm weather. I use Stew-Mac nitro paint which is thin already.

 

[Mad Kiwi]

Laying on an even, wet coat (takes practice) will allow the finish to self-level. The hard part is getting even coverage and working fast.

It makes it easier to do if you have multiple overhead bright lights and monitor your coverage by watching the reflection of those lights in the wet finish as you lay it on.

As soon as you see a mirror-like reflection, you're done applying finish there; move to areas with no/partial reflection. If you go too heavy, you'll get runs.

It's a very very fine line between too little and too much.

100% this, and heat the can. Never spray in direct sunlight, the mist drying too fast before it hits the object is a huge cause of orange peel and why a decent reflective wet coat helps.

As Peegoo said, getting just enough on so that it will settle to a smooth lake-like finish without runs is the hard part. laying it flat can help rather than hanging it vertically but that also depends on the paint type and drying speed which is heavily weather (temp and humidity) related, so t he method changes to the day.....

A lesson I was taught early in my spraying "career" (hobby really) was to do a final wet, top coat of actual thinners, it helps melt the paint and smooth it out beautifully. But that's with a spray gun setup. But it shows the same wet like concept....

 

[MAS Tequila]

Never spray any paint out in the direct sun.

Outside is just asking for all kind of crap to get in your paint.

You’re going to have to find someplace inside to spray.

 

[Full-Tilt-Tele]

Tele-Meister my friend, are your using a spray-gun or a rattle-can?​

If you are using a compressor and spray-gun, you need to thin out the paint that comes right from the can, before you spray... OR, you'll get that 'Orange-peel' finish. Paint needs to have a little time to settle down and a bit thinning gives [it] that time. Here's the stubborn problem that I've run into is; If I sand down the orange-peel and re-painting, I've got something even worst: The dreaded "Alligator" finish. The alligator comes from scratching the top surface, even with so fine with 400+ or more grit, when the fresh paint, that has acetone inside with spray-can, attacks the older coat, underside the fresh.​

Basically, too thick paint will result in 'Orange-peel'... You're best approach now, is to wet-sand with 400 grit and use some rubbing compound, following up with some polishing compound to save your product.

 

[stratisfied]

Inexperienced painters tend to rotate the hand holding the can at their wrist as they spray causing them to spray in arc. Holding the can upright, you need to lock your wrist, elbow and shoulder and then lean left or right at the waist (depending on your chosen direction of travel) to advance the paint. It's a very robotic-looking motion if you watch someone who has had a lot of practice.

Also, I do not hang the bodies up to spray. I always spray with the body laid flat on stands to keep it up off the paper. I spray the back overlapping the sides slightly first, allow them to dry and then flip the body over and do the front, overlapping the sides fully. I have always painted my bodies that way. I found out that Freeman Keller on this board (a real craftsman) uses the same method albeit he uses a detail gun and compressor. This was a validation of sorts that I had learned the trick to smoother finishes. The use of spray cans with their smaller spray pattern makes this an even more valuable trick.

It kind of goes against what you've been told about holding an aerosol can perfectly upright when spraying. You do have to tilt the can slightly as you apply the lacquer since it is not recommended to hold the can horizontally and spray directly from above. That will exacerbate problems like dripping from a bad spray tip and getting poor paint delivery from the aerosol can.

A typical spray can held at a slight angle never needs to pass directly over the top of a typical guitar body. The delivered spray pattern reaches the far side just fine with the can off to the side of the body. Just the same, this is why I mentioned in another post that I always use a full can when starting my final coat to prevent pain starvation and spitting should the paint level in the aerosol can become too low.

Some will argue that you get uneven coverage on a flat surface when spraying with the can tilted slightly. True, the near surface gets more paint than the far surface but in reality, the spray pattern is small and the difference between the film thickness delivered to the near and far surfaces is nil. I would argue that you get a more level coat because overlapping passes don't build up at the overlap where runs typically occur. No "stair-step" appearance occurs as the lacquer flows out and self-levels aided by gravity.

There are occasions where I encounter a lacquer (brand) with a crappy nozzle that doesn't give good coverage spraying that way. I just raise one side of the body slightly with a shim angling the surface of top towards me slightly which will usually correct any spray pattern deficiencies I am encountering. "Fan-spray" nozzles usually give the best coverage but very few aerosol lacquers come with that type of nozzle unfortunately.

 

[dogmeat]

To sand my current coat smooth, what grit should I use, and should I wet or dry sand it?

if its smooth I wouldn't go any lower than 1000. it its really pretty dang smooth then 1500, maybe even 2000.

if I have a run or sag I'll use 800.... maybe 600 if its pretty gross but you have to be careful. coarser papers put in deeper scratches. yeah, the scratches are tiny but they have to be either sanded out with the finer papers or filled with another coat

I always wet sand. cut the paper to useable sizes and mark the grit on each one with a Magic Marker. soak them prior to use. at least an hour but even overnight is good

you can compound after 2000 if the sanding was done right. 3000 is better

I buy high quality paper from an auto refinishing store that mostly deals PPG and Dupont products. the Meguiars sandpapers are good. Presta is another good name for compound and wax

 

[AS193]

Currently using some scrap yellow poplar for practicing my spray painting for a poplar body: sealed one side with Zpoxy and the other with Solarez polyester, hit both with 3 coats of gray sandable Duplicolor Primer, waited a day then did 3 coats of Universal White Duplicolor; 2 light coats 10 minutes apart for each and 1 heavier coat which I let dry for a day.

Coming back to it I thought I'd be able to get a smooth gloss finish for clear coat, but unfortunately both sides have orange peel to them. Is this something that every spray paint just has, or do I need to change my painting technique to avoid it? Also, can I sand it with 800 and spray over it again?

Trying cutting the last heavy coat back to two more thin coats. I think it's the thick coat that is not flowing out. Orange peel is very common, and how you deal with it is to wet sand it out.

 

[Matias]

Currently using some scrap yellow poplar for practicing my spray painting for a poplar body: sealed one side with Zpoxy and the other with Solarez polyester, hit both with 3 coats of gray sandable Duplicolor Primer, waited a day then did 3 coats of Universal White Duplicolor; 2 light coats 10 minutes apart for each and 1 heavier coat which I let dry for a day.

Coming back to it I thought I'd be able to get a smooth gloss finish for clear coat, but unfortunately both sides have orange peel to them. Is this something that every spray paint just has, or do I need to change my painting technique to avoid it? Also, can I sand it with 800 and spray over it again?

I’d sand / steel wool and spray again.

 

[ashtone54]

Nobody has mentioned what to use when wet sanding. Don’t use water! Use naphtha or mineral spirits, because water will swell the wood grain. When you sand on these swollen areas, after the wood dries and contracts, you’ll have a rut in the surface.

 

[stratisfied]

Nobody has mentioned what to use when wet sanding. Don’t use water! Use naphtha or mineral spirits, because water will swell the wood grain. When you sand on these swollen areas, after the wood dries and contracts, you’ll have a rut in the surface.

You don’t wet sand until the wood is fully encapsulated with primer or finish. If you’re wet sanding through your finish into the wood, you don’t have enough finish on it or just don’t know when to stop sanding.

 

[58Bassman]

Currently using some scrap yellow poplar for practicing my spray painting for a poplar body: sealed one side with Zpoxy and the other with Solarez polyester, hit both with 3 coats of gray sandable Duplicolor Primer, waited a day then did 3 coats of Universal White Duplicolor; 2 light coats 10 minutes apart for each and 1 heavier coat which I let dry for a day.

Coming back to it I thought I'd be able to get a smooth gloss finish for clear coat, but unfortunately both sides have orange peel to them. Is this something that every spray paint just has, or do I need to change my painting technique to avoid it? Also, can I sand it with 800 and spray over it again?

Why are you using primer after ZPoxy or Poly? I have used Zinsser primer, sanded it and sprayed house paint and it didn't have orange peel.

Was the paint cold? That causes more texture than warm paint. A technique used by people who spray gelcoat is to put the cans in an old Nesco roaster, to raise the temperature and allow the gelcoat to flow better. It doesn't need to be hot and it's not in pressurized cans- that could cause the cans to blow.

Start sanding with 320, but don't use heavy pressure, followed by 600 grit. That should be fine enough and starting with 800 will only result in clogged paper.

Maybe you could let the Duplicolor dry a bit longer- what was the air temperature when you sprayed it? This was from a can, right?

 

[MarkieMark]

Personally, I'd suggest experimenting with something other than enamel next time.

I have had bad results attempting to sand enamel due to the "never really dries hard" syndrome. It often makes matters worse by revealing the finish under the skin on the high spots... It just doesn't give the desired result no matter what I do.
Enamel is fine for some things, but IMO not where you want a finer smooth finish.

You can get other formulations in a spray can BTW. Though maybe not to many options from the local hardware.

 

[Havins]

If you're going to spay rattle cans you're stuck with orange peel. I hate rattle cans because of this and the changing of pressure as you use them. On a small area like a guitar the pressure change won't be noticeable but if you are spraying a larger surface area like a car fender or hood it will be very noticeable. I no longer use it straight from the can. If I want to use the paint from a can I spray it into a glass jar then pour it into one of my paint guns. I use Sprayit LPLV guns as they match better to smaller compressors. To decrease the orange peel use laquer thinner with lacquer paints or paint thinner with non lacquer oil based paints. Most of the orange peel comes from the paint drying too quickly to self level. Thinning the paint slows down the drying time letting the paint self level better. You can also purchase reducers to do the same thing. Sometimes its just cheaper and easier to buy a new body that is already finished. Eden Allen bodies are cheap and accurately made.

 

[eallen]

While there is clearly no need to chime in with the responses, I'm bored.

Orange peal is not inevitable with spray cans. What they lack in adjustment requires the painter to supplement in technique. Take the chart Freeman posted earlier and select the items you can control with a spray can and focus on those. Spraying speed over the surface, distance, heaviness of coat are primary. If spraying a clear after a liquid ahiny gloss cost isn't needed as much as a smooth coat. The surest cure for rough or even runs in coats is practice until they aren't.

Dry sand only between layers and follow the manufacturer instructions, usually 400 grit max. Never spray in direct sun or set a finish in the sun after spraying.

 

[Lakeabilene]

be sure you have the right kind of light when you are spraying so you can judge how much to put on. Guys that have spray booths and do great painting on cars, usually have a tower of flood bulbs on the left and on the right to reveal the tiny issues and slightest problem

 

[trev333]

for colour I mostly use duplicolor spray cans.... it seems to lay down ok..

about as smooth as I can get off the can. no sanding between coats. I probably started my clear straight over this without flat sanding, just knocked any dust/floaters off...

not my first effort, that's for sure. It takes practice...and a bit of zen...

 

[martinlb]

I always sand between coats, let all coats completely dry, hit the final coat with up to 2000 grit, polish, wax.

Absolutely on target I think. Very, very light sanding with the coarser grits will help prevent scratches that go too deep to come out. Wet sanding with 2000 grit and then even polishing should put your project right where you want it. Best of luck to you!