Thinning Killz 2 primer for sraying..

[Michael Dunn]

I have a fairly large assembled project that needs to be primed and painted. It is constructed of MDF. I would like very much to be able to spray on the primer and paint. I think this would be much less stress than brushing all of the dreaded inside corners.

Has anyone sprayed on Killz 2 primer with success? If so, what did you use to thin it?

Thanx,

shotgunn

[Joe Chritz]

I haven't sprayed the kilz but I do spray a zinseer water base primer that I thin with water. Shouldn't be any big difference.

You should be able to do the same with the kilz.

I am using the new formula pro-classic that I thinned about 10-15% with water for a top coat and it sprays well.

The zinseer primer calls for two coats if it is thinned.

Joe

[Jack Wilson]

I have done a LOT of spraying, but sorry not with Kilz 2. However seeing as its water based, and I have at least (2) 5 gallon buckets of it in the barn, hold on...sorry, I have Kilz Premium, also water based, it says add a small amount of water for spraying. It doesn't specify how much is a little. I would think 1 cup for 5 gallons is a lot. I have 2 low end pressure airless sprayers, $400 each, (to help identify where low end is), and have sprayed close to a thousand gallons in the last couple of years, I have never thinned.

[Phil Phelps]

Nothing will work primer into the pores of the MDF like rolling and brushing. Spaying tends to lay on the surface. I think an alkyd primer is even better.

[Michael Dunn]

If I roll and/or brush the primer on, will I still get the super smooth look and feel if I spray on the paint over the primer?

Nothing will work primer into the pores of the MDF like rolling and brushing. Spaying tends to lay on the surface. I think an alkyd primer is even better.

[Joe Chritz]

Primer is often scuff sanded which will help in keeping a fine finish after no matter how it is applied.

One thing to remember is that paint telegraphs every flaw. At least you can fill them with sandable puddy and repaint.

Spraying inside boxes isn't exactly a "pick up an HVLP and do it" sorta thing. I expect it to be easier with paint since over spray is what causes a lot of grief and there is less with the thicker paints.

I just finished spraying a gallon of Pro-Classic and over two coats of the Zinseer primer it is very flat and smooth. Nothing special other than a scuff sanding on the first primer coat.

Joe

[Michael Dunn]

What exactly is 'scuff' sanding? I have never heard of that technique before. I am certainly no expert on finishing.

Primer is often scuff sanded which will help in keeping a fine finish after no matter how it is applied.

One thing to remember is that paint telegraphs every flaw. At least you can fill them with sandable puddy and repaint.

Spraying inside boxes isn't exactly a "pick up an HVLP and do it" sorta thing. I expect it to be easier with paint since over spray is what causes a lot of grief and there is less with the thicker paints.

I just finished spraying a gallon of Pro-Classic and over two coats of the Zinseer primer it is very flat and smooth. Nothing special other than a scuff sanding on the first primer coat.

Joe

[Joe Chritz]

Scuff sanding is just a quick intro to the sanding medium. I use sanding sponges almost exclusively for finishing. Door, sponge, sponge, door, move on to the next one.

The entire purpose is just to knock down anything that might get in the finish or in the case of a first coat any grain raising and the like. A cabinet door might take 10 seconds to do both sides.

The only time I would sand more than a "scuff" is if I am using polyurethane, in which case finishing time windows and a mechanical scratch pattern is important for bonding.

Joe

[Phil Phelps]

Michael, just knock down the nibs with 220 sand paper and your ready for the finishing coats. I doubt that one coat will seal the pours in the MDF. I've said repeatedly that I trowel on joint cement and trowel it smooth. When it dries to a haze, I use 220 and then start the prime.

[Phil Phelps]

Michale, I was concentrating more on the MDF than the Kilz. I've have experience with the "old" Kilz but not the "2". I would not recommend using Kilz as a wood primer, especially if you were brushing. It dries way too fast and creates a "rope" effect that is unsightly, to say the least. It was mostly used to hide stains on walls such as mildew, smoke, tobacco, etc. I'm sure they have made improvements over the years and probably have a water base version. But, I'd stay with an alkyd wood primer. I'm partial to Ben Moores, Underbody primer.

[Michael Dunn]

O.K. So I ended up going with Killz oil based primer. I have scuff sanded, primed (rolled it on), scuff sanded again, and put a 2nd coat of primer on the base of my project. Should I scuff sand again before I paint?

I have brushed on the first coat of primer inside of the cabinets, I would like to spray on the 2nd coat. Because of all of the corners, the brushing doesn't look all that great.

Per Home Depot's recommendation I purchased a strainer and some paint thinner. They say that I can thin the oil based primer like that. Should I add 10% thinner?

Also, how do you recommend cleaning the sprayer?

Sorry for all of the ?'s, I am new to painting MDF.

Thanx,

shotgunn

[Joe Chritz]

Depends what kind of sprayer you are using. A HVLP gun will require the material to be thin enough to function. You can start at 10% and add until it is the correct viscosity. Ideally you would use a cup designed for testing that but if it sprays OK it is fine.

Clean the gun according to manufacturer recomendation using what ever thinner is needed. I avoid oil base stuff for just that reason.

Once the MDF is primed it paints like everything else, actually a little better usually.

Joe

[Michael Dunn]

I only have a small pancake compressor for now and I do this type of work at 12:30-2:30 a.m. so for now HVLP is out of the question. Due to the fact that the compressor would probably be on continuously, which would actually be about 30 seconds until my wife runs in screaming! LOL!!!

I bought a Harbor Freight electric paint sprayer ($15, worth a shot, right?) it has a cup for checking viscosity. It says that the cup should drain in 15-30 seconds for optimum spraying.

I think I too, will avoid oil based stuff, for now at least. Too much hassle. I do like the way MDF takes paint though.

Thanx, I'll let you know how it turns out.

shotgunn

Depends what kind of sprayer you are using. A HVLP gun will require the material to be thin enough to function. You can start at 10% and add until it is the correct viscosity. Ideally you would use a cup designed for testing that but if it sprays OK it is fine.

Clean the gun according to manufacturer recomendation using what ever thinner is needed. I avoid oil base stuff for just that reason.

Once the MDF is primed it paints like everything else, actually a little better usually.

Joe

[Michael Dunn]

Wow, this sprayer (or myself) ABSOLUTELY SUCKS!!!! I don't know if I did something wrong, but I couldn't get a decent spray pattern.

Any other spraying tips or advice? Should I rent a sprayer? Or just bite the bullet and brush it on?

It doesn't have to be 'perfect', I just don't want it to suck! This is for a table saw/routing/storage/work center.

Thanx,

shotgunn

I only have a small pancake compressor for now and I do this type of work at 12:30-2:30 a.m. so for now HVLP is out of the question. Due to the fact that the compressor would probably be on continuously, which would actually be about 30 seconds until my wife runs in screaming! LOL!!!

I bought a Harbor Freight electric paint sprayer ($15, worth a shot, right?) it has a cup for checking viscosity. It says that the cup should drain in 15-30 seconds for optimum spraying.

I think I too, will avoid oil based stuff, for now at least. Too much hassle. I do like the way MDF takes paint though.

Thanx, I'll let you know how it turns out.

shotgunn