Newby at HVLP - Questions

[Steve Kohn]

I have purchased a used Fuji Q4 Pro system with the intent of spraying my projects. I build everything from small boxes to large case goods. I would like to start spraying shellac, SW Proclassic paint, transtint dyes, and Target coatings EM6000. So I looking for the expertise on this board in the following areas.

I would like to know what needles and caps will work with these kinds of finishes. I do have the manual for the Fuji, should I just use those recommendations?

What is the best way to dial in the gun to get the best performance for these finishes?

What is the best method of cleaning the gun?

If putting multiple coats of the same finish on the workpiece, do you have to clean the gun after every coat?

Thanks in advance for any available advice.

[Jeff Wright]

I will be doing spray finishing with my as-yet-unused 4-stage system, so I will look forward to replies to your request as well. In the meantime, you may want to buy Jewitt's Spray Finishing Made Simple available for $16 at Amazon. I just got it and find it very helpful with your questions. See:

http://www.amazon.com/Spray-Finishing-Simple-Taunton-Press/dp/1600850928/ref=sr_1_1?ie=UTF8&s=books&qid=1265996795&sr=8-1

[Chris Friesen]

When you decide to do hvlp you don't mess around! I'm looking at the mini-mite3, myself.

I'm definitely a novice, but I've been reading everything I can find so take the following for what it's worth.

The guys at Fuji said the #4 needle should work with most finishes. The #3 is similar but with a smaller flow rate...if you've got it, you might want to use that for dyes. Shellac is very forgiving, especially since you're likely to be rubbing it out anyways. For paint you'll likely want to thin it and maybe use some Floetrol to give it more time to level.

As for your other questions, I'll let the others answer.

[Steve Kohn]

Actually I am not a complete newby at spraying. I bought a Central Machinery single stage machine and have used that for a couple of projects. It was OK for some things but simply not powerful enought. So when I found the Fuji on this forum I jumped on it. Now I need to really learn out to spray, thus my questions.

[Jeff Monson]

When spraying shellac or the em6000 you should be able to use the same tip. I use a graco system and it sprays the em6000 without thinning very nicely.

Shellac dries very quickly so I would not leave it in the gun too long, the em6000 will give you a little more time but I would not recemmond leaving it in the gun for more than an hour or so. ( you will get varied opions on this)

I usually use laquer thinner to clean my gun when spraying solvent based laquer or shellac. Just pour out the unsprayed product and fill the cup about 1/2 way with clean thinner and give it a few good shakes, then run about 1/2 of it through the gun and you are done. I clean my gun with soap and water when I spray em6000.

I never clean my gun between coats, I'm usually applying another coat within an hour or two so I dont clean it until I am done.

You have a nice system that will last you for years to come, and will give you outstanding results. Just be sure to practice, practice on some scraps to determine correct flow settings and techique.

Also, dont go crazy with the em6000, it goes on with a little orange peel but levels out nicely when setting up, its tempting to put on more product but its not needed.

[Jim Tobias]

Jeff,
I do not claim to be an expert, but I am a hobbyist that has a Fuji Q4 and have used it a couple of years with Target finishes. I have used both the #4 and #3 tip with the Target products. I had only been using the #4 until recently and I tried the #3 because I was getting some small imperfections with the #4. I also think I was probably putting it on a little too thick. Using the picture below as a guide: I found that if I only open the metal knob(controls the volume of fluid) about 1 - 1.5 turns out, I have better success. More than that and I can easily get too thick a coat and trap air bubbles. You will have to play around with the Metal collar on the front of the gun that controls the size of your spray pattern. I also learned that you DO need to get close(8 " or so) to get a smother coat to lay down.
As for the Target finishes, I have not found that I needed to thin them at all wiht one exception. I added black mixol tint/dye to some EM 6000 and did thin it slightly(5% distilled water) that seemed to help it flow out a little better.
I think you will really love your Q4 as your play around wiht it. I have even sprayed latex paint with the #6 tip. The site says use the #4 but I coul dnot get that to work so I tried the #6 and that worked fine.
Hope this helps ,
Jim

[chris dub]

I'm new to spraying too and picked up a capspray 5 stage unit. I had a 2 stage and it felt limiting so I figured I'd overcomnesate for my lack of skill with better equipment:). I am trying to get the right technique to apply enough material, but not so much for that it runs. Luckily we recently moved so I have a good supply of cardboard to practice on. But I will say I got lazy with my 2 stage gun and left the finish for a few days and it clogged pretty good. I'm trying to be better and clean it at the end of the day.

[Bob Barry]

I saw that this thing gets great reviews so I bought one because i was tired of brushstrokes / stipple (amateur, I know) on my doors and trim (currently doing baseboard).

I did find one thing that is disappointing but it is not a problem with the Fuji system - it has worked very well as designed. It provides an amazing amount of control - three adjustments at your fingertips - fan size, air/paint ratio, and airflow at the hose control.

My problem: the gloss is almost gone when you thin the paint to the point that it is able to be sprayed ( mine = 60% paint, 40% water/Floetrol ). After seeing that this was the case, turns out that this is a known problem with thinning gloss paints - I just did not see it until I was looking for a solution. I was using SW Pro Classic Latex Acrylic High-gloss white.

It may be that I've done something wrong but this was my finding. I will be happy to be told I'm wrong if also given a solution!

:(

[Chris Friesen]

My problem: the gloss is almost gone when you thin the paint to the point that it is able to be sprayed ( mine = 60% paint, 40% water/Floetrol ). After seeing that this was the case, turns out that this is a known problem with thinning gloss paints - I just did not see it until I was looking for a solution. I was using SW Pro Classic Latex Acrylic High-gloss white.

What about top-coating your existing job with a gloss clearcoat?

For future jobs you might consider a waterborne white pigmented lacquer. It might spray better than a way-diluted latex.

[Henry Ambrose]

I saw that this thing gets great reviews so I bought one because i was tired of brushstrokes / stipple (amateur, I know) on my doors and trim (currently doing baseboard).

I did find one thing that is disappointing but it is not a problem with the Fuji system - it has worked very well as designed. It provides an amazing amount of control - three adjustments at your fingertips - fan size, air/paint ratio, and airflow at the hose control.

My problem: the gloss is almost gone when you thin the paint to the point that it is able to be sprayed ( mine = 60% paint, 40% water/Floetrol ). After seeing that this was the case, turns out that this is a known problem with thinning gloss paints - I just did not see it until I was looking for a solution. I was using SW Pro Classic Latex Acrylic High-gloss white.

It may be that I've done something wrong but this was my finding. I will be happy to be told I'm wrong if also given a solution!

:(

What does the instruction manual say about spraying latex?
Which tip and needle do they suggest?

White lacquer is a good idea.

[Phil Phelps]

What does the instruction manual say about spraying latex?
Which tip and needle do they suggest?

White lacquer is a good idea.

The instruction manual should say, "Don't expect a good job when using paint".
Spraying latex paint through a HVLP is useless. You use an airless rig for that. When you water down paint and run it through a siphon or HVLP gun, you will flatten the gloss. If you brushed your cabinet and spray your doors, you'll get a different sheen. You folks who use Floetrol as a "thinner" are not going to get any better results. I've used Floetrol for decades when brushing latex. The label used to describe it as an "extender" and is uesd for less drag on the brush and leveling purposes. It has done nothing for me when I had to thin paint to get it to flow through a spray gun. They changed the label but the results are the same. For those who buy a HVLP and think they can spray their house are in for a rude awakening. Practice and patience will be your best training. Spraying a six inch jewelry box isn't the same as spraying a 4x8 panel with lacquer in 105 degree weather.

[Chris Friesen]

You folks who use Floetrol as a "thinner" are not going to get any better results. I've used Floetrol for decades when brushing latex. The label used to describe it as an "extender" and is uesd for less drag on the brush and leveling purposes.

Fuji suggests using their larger needle (2.2mm) when spraying latex on any sort of larger surface. That way the paint doesn't need to be thinned as much but also doesn't atomize as finely, so Floetrol is used as an extender (not a thinner) to let the paint level better after hitting the surface.

That said, I totally agree that for any serious usage an airless is the way to go.

[Phil Phelps]

Chris, it really is. Paint wasn't meant to be reduced by 20-50 %. You can get away with small projects from time to time. Floetrol is a great product when used as it's intended.

[Henry Ambrose]

Phil has it mostly right.

But not the part about needing to go airless. You -do- need a powerful enough HVLP to spray your selected paint. Granted, most of the outfits we write about here are not powerful enough to spray latex. The typical top of the line fine finish versions will spray latex with some thinning. All you need is water, not Floetrol as Phil mentioned.

If you plan to spray latex, pick a gun that is rated for that use.

From the Fuji site:
What is the Secret to spraying Latex Paints?

1) Use the Aircap Set #4
2) Thin the paint somewhere between 20% - 25% with water
3) Add Floetrol Latex Conditioner to slow the drying
4) Add the 6ft Whip Hose to reduce air temperature through the gun
5) Hold the gun no more than 8" (20cm) away
6) Apply a full, wet coat (wet like a lake)

You need more power to be able to spray latex straight. Look at pressure feed outfits.