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HankB

Valspar Tractor and Implement Enamel

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HankB

Hi folks,

I'm using Valspar Tractor and Implement Enamel in a Harbor Freight gravity feed gun. At present I'm struggling with orange peel in the results. I've done some searching on this and found that the following things can lead to that:

- insufficient pressure which results in poor atomization.

- excess paint flow also resulting in poor atomization.

- insufficient reducing ...

- high temps resulting in paint drying before it has a chance to level out.

My question to the experts here involves reduction. I used mineral spirits at the rate of 2 oz./qt. as recommended in the directions. (Same ratio as the hardener, in fact.)

I went back and read the directions. Again. :) I saw that Valspar recommends naphtha for spraying and mineral spirits for brushing or rolling. My research told me that naphtha results in faster drying than mineral spirits. It seems to me that mineral spirits would result in slower drying and more time for the paint to level out. Is there something I'm missing here? Is there some other characteristic about naphtha that causes it to level out better?

Also, is the ratio of 2 oz./qt. a limit or a suggestion? Can I add more reducer - say 3 oz - to get better resistance to orange peel at the cost of having to spray additional coats?

One of the issues I'm dealing with is working in high temperatures. Ambient around here has been going into the 80s pretty much daily for the last 7 or 8 weeks. (Upper 80s predicted for the next two days.)

My next adventure in painting is to learn how to wet sand before I spray the next coat.

thanks,

hank

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Kelly

Thin the paint a bit more, and remember to wait between coats, you should be good, practice on a old hood or something, just remember to sand the panel smooth so it has the same feel as the parts your painting, thin paint till it sprays nice, seems like a waste of paint, but if you mess up it's not your parts you need to look good.

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Save Old Iron

If this is the HVLP gun from harbor freight, they do require a very high volume of air from your compressor - I use the same gun but have a compressor than can deliver over 12 cfm of air. If your compressor is smaller, you might be starving the gun with low airflow and poor atomization of paint.

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300zx

I used the same paint and hardener with naphtha and I had the same problem in a Kobalt (Lowes) hvlp gun. I thinned it another 1 oz beyond what they recommended and it helped. I may try 4 oz the next time to get it to flow out even more. I had the same problem with heat. I left my pieces in the sun before I painted them and they probably got too hot. I plan to keep everything in the shad the next time.

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rmaynard

The only difference between naphtha and mineral spirits (as far as thinning is concerned) is the evaporation rate. Naphtha evaps more rapidly.

My experience tells me that orange peel is usually a result of the finish drying too quickly and not having the time to flow out, and improper atomization at the spray gun tip. That can be caused by lack of pressure and/or volume.

Always be sure that the finish you are using, and the item being painted are at the same temperature, and follow manufacturers guidelines on temperature and humidity conditions for paint application.

Bob

ps. The above info is from 25 years of refinishing antique furniture.

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Jim_M

Thin the paint a little more and crank up the air. The low priced guns come with a bigger orifice in the mixing cap, more air will help atomize the paint.

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Ken B

I would lean towards the paint not being thinned enough and if you are painting in high humidity that will cause problems as well. Get yourself a test panel and thin and adjust air pressure till the results are decent. If you already have the orange peel on the tractor you can wait till it hardens up some then wet sand and buff it out.

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HankB

Thanks all for the tips and suggestions. I know that skill won't come without practice, but it will help to have some ideas on how to get better results.

-hank

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squonk

I'm certainly the last person anyone would seek painting advice from but my past experience with automotive acrylic enamel was paint with TOO MUCH thinner dried faster, didn't flow as well, and had more orange peel.

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wh79d160

If you can't or don't plan to correct the problem on what you've already shot, you can alway color sand ( wet sand) w/800 or 1000 grit & polish off the haze if you have buffer & some compound. Good luck, Tom, Perry Ks.

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PPGman

Hank, there are several things that can cause you orange peel problems that i can think of off the top of my head. Air pressure, paint viscosity, and air temp are the 3 big ones. Other things that cause it are fish eye additives, as well as some hardeners.....typically found in economy paint.

I actually just shot a trailer with the valspar a few weeks ago just to get a feel for it since so many guys here are spraying it. I have to say, i thinned the first go-round with the naptha, and i had a ton of orange peel as well. It took several hrs for the solvent to flash out and it stayed "tacky" for a good 4-5 hrs as i recall.

The second go-round i mixed up, instead of thinning it out with naptha, i ended up using some old 80degree ppg enamel reducer i had laying around. I also kicked the air pressure up another 10psi, and closed off the fluid valve a bit. As far as thinning goes, i was somewhere in the neighborhood of 2 parts paint- 1 part reducer. I have to say, it layed out pretty nice, and was tack free in half the time. Sometimes the best way to deal with paint your not familiar with is to get yourself a scrap panel and see what works and what doesn't. Most of the time you can play around with it a bit and get a feel of what works best before you start spraying your project. I know this is not what the instructions say as far as applying their product, but it worked well for me. Using a specific temp reducer not only accelerated the drying time, but seemed to help with how the paint layed out. I have never been a fan of mineral spirits or naptha when it comes to spraying, but thats just my preference.

What others have said about the air compressor is true also. If your compressor is not keeping up, your air pressure will eventually drop and so will your ability to atomize the paint properly. You can purchase a mini regulator/ air guage for your spray gun for 10bucks or so, and this would let you keep an eye on what kind of PSI is actually ending up at your gun cap. Even a small air compressor can provide enough air to paint a few pieces at a clip.....you just may have to plan accordingly and stop and let your compressor catch up between coats.

Keep playing with it, until you find what works for you. Good luck. :)

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