Trying to achieve a better finish

[jon claw]

I have a few questions about spray finishing. I bought one of those Earlex HV5000 a little while ago for a few smaller projects and it was "OK". Realizing my finishing needs were becoming a little more extensive, I bought the Fuji Q4. I also got the whip hose. My main questions are these:

1. I have had it on the top shelf of a cabinet since I got it, since it is off the floor and out of the way and I just coil/uncoil the hose and go, and have not had a problem. However, I just read that they recommend not to place it up high. How bad do think this would be for the turbine?

2. I am not an expert but I'm striving to get a professional looking/feeling finish. I know, practice, practice, practice. When I look at the finish, it looks pretty good and I'm happy with that aspect. My problem is the way it feels. It doesn't feel like garbage but I've worked in shops where the finish feels like glass. Is my problem the product I'm spraying or is there an end step that will "soften" the feel of the finish. I've read some finishing books and have the Jeff Jewitt "Spray Finishing Made Simple" DVD/book and try to stick to the guidelines discussed. Any tips on product or technique would be great. I mainly use WB finishes.

3. My last question is what would you do with the Earlex? Sell it? Throw it off a bridge? Use it to prime with and shoot with the Fuji? I don't know, just curious.

[Chris Fournier]

Without really good photos it's hard to give you really good advice. Free advice being what it is I'll offer some anyways!

As far as the turbine goes I've never read about not having it up high. Perhaps it's a heat thing. As the turbine runs it fills the space with more and more hot air (like me in a pub) if so unless it is a very cool humid day your airstream is likely getting pretty warm and dry and this leads me to my advice regarding your finish surface comments. The turbine on the floor will take in the coolest air available.

If your sprayed surface isn't glassy smooth off the gun I'm not surprised, this is very tough to achieve - I'm talking about "glassy smooth". "Very smooth" isn't tough to achieve.

An HVLP propels the finish with a high volume of warm dry air, unlike a conventional HPLV set up. Often times, this warm air can cause the finish to actually start drying in the air before it contacts the intended surface. The result is a fine pebbly texture. If this is your problem, then you can turn down the air a bit at a time or increase the finish volume settings on your gun, and/or add a retarder to your finish or spray in cooler conditions in order to get a thoroughly wet film that levels nicely on your piece.

The other time that you can get a rough finish occurs when you are spraying into a "box" like the inside of a cabinet or drawer. The finish actually bounces off the intended surface (and the over spray settles) on the other surfaces nearby. Same effect as above, you have a not entirely wet film that comes out pebbly or rough. In this instance you have to have the "pressure" down very low and keep the spray wet. For drawers I try to leave the bottoms out and finish them seperately. This helps immensely.

Hope this helps you out.

[Tony Bilello]

........... For drawers I try to leave the bottoms out ...............

I knew there was something deeply weird about you.

[Tony Bilello]

I have the Earlex 5000. It is the only HVLP gun I have ever used so unfortunately, I can't make any comparisons but here is what I have learned.

1). The 1.5 tip for me is only good for spraying analine dye.
2). The 2.0 tip works great for my vinyl sealer without thinning.
3). I use the 2.0 tip for pre-cat lacquer and the likes. In my case, the pre-cat I use is about 27% solids by weight and is recommended to be used straight with no thinner. If I do this, the finish has an orange peel look to it. I must thin at least 25% to 30% or more the get it to spray the way I like.
4). Because of the warm air from the gun, the lac sets up fairly fast, which is a good thing in the cooler months. Not so good in the warmer months. Every time I open a can of lacquer for the first time, I automatically add retarder regardless of the humidity. I do it to slow down the set-up time. I also automatically add fish-eye eliminator because I do a lot of refinishing.
5). My 2nd coat of pre-cat, which is also my final coat, is applied with about 40% or so thinner to give me a really nice flow. At this point I am not concerned with 'build', I just want it to lay flat.
6). I have been meaning to get the 2.5 tip for my pre-cat lacquer. Maybe the bigger oriface will spray better. I just haven't got to it yet.
7). I made a small cart for my Earlex for 2 reasons. It has a way of hanging up the unweildy hose. I got tired of stepping on it. The second reason was that the filter underneath gets clogged rather easily with dust when siting on the floor. On my small cart, which is probably no more than 2 feet off the ground, I made a hole in the top of the cart slightly smaller in diameter than the Earlex. This keeps the unit off the floor and the filter stays much cleaner. Oh, the small wheels help a lot when pulling the cart while spraying.

Tony B

[Chris Fournier]

I knew there was something deeply weird about you.

If this was a motorcycling forum you would have me dead to rights.

[Tim Sproul]

Jon,

With water based finishes, it is important to have stainless steel fluid passages. Aluminum and some other metals can react with some water based finishes, causing the finish to start to cure and giving you particles.

Do you strain the finish just before adding to the cup?

Are you spraying in a dust free environment that also moves the overspray away from your work?

I'm assuming you knock down dust nibs and raised grain after a coat or two of sealeror finish.

Are the fluid passages clean and is the filter for your turbine clean and installed properly?

[John TenEyck]

I, too, would guess that your finish is drying before it's had a chance to flow out. I had this same problem when I started spraying. My solution was to make sure I had my gun the proper distance from the workpiece and to slow down the speed I pulled the gun across the surface so that I was putting on a wet coat of finish. A little practice on some cardboard cured my problems.

[jon claw]

Thanks for the tips guys.

Chris, I have never used a retarder before but I will start looking into it. To tell you the truth, I may have come across using one before, but I'm pretty unfamiliar with them. Do they just help a finish cure at a slower rate? I do shoot my drawers, and boxes when possible, without the bottom/back. I saw the guys in the shop I used to work at doing that and I thought it would limit blowback.

Tony, I noticed the same thing with the Earlex. During the winter, everything seemed fine. Then, when summer came on, the air was curing everything way too quickly. I don't know if this is what is happening, but now that I use the Fuji, the hose is 3x as long so maybe the air is cooled by the time it hits the gun and it shoots really well. Just a thought. You seem to have a lot better handle on finishing than I do. Are you shooting water based finishes as well? I haven't ever come across fish-eye eliminator. What does it do exactly? Help flatten things out a bit better?

Tim, I have been using Benite to seal with. Maybe you have a sealer product that you like using that you'd be willing to recommend? I do strain everything. I sand between coats. I'm not sure what you mean by "knock down dust nibs" other than sanding. I'd love to hear any step by step process you do and which product you use. My spray area is cordoned off with three floor to ceiling tarps and the forth wall consists of 2 filtered fans, for overspray/ventilation, with panels to close it off. I blow it all down about half hour before I spray too.

John, I probably do need to practice more but it always seems like the texture test is lost on cardboard. My pattern always seems nice though.

Thanks again and please add anything if you feel like it.

Cheers!

[Tony Bilello]

..........
Tony, I noticed the same thing with the Earlex. ........ when summer came on, the air was curing everything way too quickly. I don't know if this is what is happening, but now that I use the Fuji, the hose is 3x as long so maybe the air is cooled by the time it hits the gun and it shoots really well. Just a thought. Are you shooting water based finishes as well? I haven't ever come across fish-eye eliminator. What does it do exactly? Help flatten things out a bit better?..........

Cheers!

Jon

Like I stated earlier, I dont have any experience with any other HVLP to compare to, but I'm sure you get what you pay for. I believe your gun retails for around a $1,000 or so. I have heard good things about the Fuji. I am sure by the end of the year, I will end up with a Fuji also. The Earlex hose is kinda short for my usage. I move quickly when I spray.
I havent shot water based yet and dont plan on it at this point in time. The new technology seems to be going in that direction so I am sure it will improve in the near future.
Fisheye eliminator is used mostly in refinishing. Sometimes after stripping, the furniture may still have some silicone or oil residue left in it. Most times it is caused by many years of using furniture polish that permiated the finish. When you spray over those unnoticable areas, the lacquer pulls away from that spot and causes very small but noticable spots in the finish that look like fish eyes or miniature spiral oil slicks. The fish eye eliminator helps prevent this from happening. Note that fisheye eliminator makes the lacquer glossier. Rarely is fisheye elimimator used on new wood.
Retarder slows down the set-up time of lacquer. It's most advantageous and used mainly during high humidity days. When spraying during high humidity, you get a condition called 'blush'. Essentially, the moisture in the air gets trapped in the lacquer and the finish looks foggy. The retarder slows down the set-up time of the lacquer allowing the moisture to escape before the lacquer skims over - sometimes. The slowing down by the retarder is measure in only a few minutes so it doesnt really effect your recoat time by very much at all. That is one of the advantages of a turbine system in colder months. Cool humid air is heated up and by the time it hits the gun the higher temperature basically reduces the humidity of the air going through the gun.