Spraying Lacquer

Had an interesting experience today which I thought I'd share with other lacquer spraying novices (experts can stop reading now...)

I'm embarassed to say I've been trying for years to get really good (OK, I mean great) lacquer spray finishes. It's been a long (LONG) journey through lots of equipment ugrades, spray booths, trips to Perth to speak with Becker Acroma re lacquer hassles, and LOTS of reading and still more phone calls to Beckers, etc etc. (I think they got sick of hearing from me..) Up to now I've managed just "OK" finishes, but always seem to not get it right, with some minor orange peel problems, runs, or other hassles. And it seemed such a struggle regarding correct gun settings. How much fluid, how much air, etc etc.

This afternoon the furniture finisher for a local furniture gallery came by and we sprayed 3 pieces of furniture I'd prepared for the occasion. I was doing it all wrong.

Here's how this guy did it..... LOTS of air from the gun (almost wide open). Fair amount of fluid (say about half open or more at the gun setting). And full cone of spray regardless of workpiece shape / configuration. When he set the gun up that way I was like, whoa, this'll be good (expecting too much air, fluid and cone to cause problems). What he did next was the real eye opener. Whereas I always dawdle my way down workpieces to get full coverage (I've had to as I was throttling down the air & fluid) this guy FLEW down. I mean he was spraying like picasso. Very steady and very carefully positioned (about 150 - 250 mm above the workpiece). But quite fast!! First one complete coat, then immediately back over the whole piece again. Repeating the same sequence. I was gob smacked.

Along the way he was explaining the logic behind which surfaces he sprayed in what order, from what direction and what angle (differs for edges, tops, sides, corners, legs, rails, etc etc.).

I then sprayed the last piece under his guidance. Best spray job I've done so far. His work was perfection.

Another thing I learned.... he mixes his lacquer in the ratio 10:1:6

10 parts lacquer (Becker Acroma DM 307, 30% gloss)
1 part hardener (acid catalysing hardener)
6 parts thinners

This is about 2 parts thinners more than I'd been using. He normally applies 3 coats for the gallery work. But 2 is OK - with the double application per coat.

It would be very difficult to learn this technique without getting hands-on teaching - to get an appreciation for speed of application, sequence of spraying, etc. So if anyone out there is having lacquer spraying hassles, I'd highly recommend, FWIW, to find someone experienced to give you some live teaching. Maybe other furniture finishers spray differently to this guy, or have mastered a different technique that works for them. But at least you'll learn something that really works. (If you're in West Aust and want to see the results of his spraying, drop into Boranup Gallery south of Margaret River...)

Hope this info is of some interest / help to others...

Richard

mate you just got me all exited...i was just thinking of a faster way of applying my finishes, french polish and varnish (or maybe lacquer would be better} i don't need a piano finish as i use recycled timber, but still a low sheen/semi gloss...what would you reccomend , and what would it roughly cost to set up???

Huerta, lacquer finishes offer the quickest method I'm aware of to finish large and / or complicated pieces. Maybe there are other quicker ways, but I don't know about them. I've been through a steep learning curve since I started finishing in 1999. I started with organoil which darkened and flattened my finishes. I later learned I was not "working" it properly. It takes LOTS of work and time to get a good oil finish. And even then it's not going to give a good satin finish, IMHO. So I went to oil / varnish combinations (Danish, Floorseal and my own mixes). These worked very well, gave great finishes, especially when sprayed on with a little turps added as thinners. But again it was a fairly time consuming exercise with an overnight wait between coats. Then I discovered lacquers. Using 30% or 40% gloss lacquer gives a really fast & beautiful, hard wearing and waterproof satin finish. It's worth looking into. But learning how to spray properly has been a struggle for me..

Good luck with it,

Richard

Hi Richard,

Well, here I am with a gun and compressor too scared to use them on lacquer for the same reasons you mention. Have had much and varied advise from casual users all of which still had me very hesitant to try it and maybe ruin a job but your post has given me the confidence now to give it a go. Mind you I know little about lacquer. So thanks for the information, much appreciated. Next time I go down south I will drop in to the gallery. By the way, I ony have a cheap gun, works OK for painting the house. Is it worth the expense to buy a professional gun specifically for lacquer or is it an actual necessity to have pro gear, and if so, could you recommend one.

Many thanks
Pops

Pops,

My hunch is that someone who's an experienced spraying "expert" could probably do a good job with a "garden hose" and tin can. You could spend lots on a full pro set-up and still do a lousy job if you don't learn to operate the gun correctly - and learn a technique that provides good even coverage. There are probably different techniques by different experts, but each one enables the pro to use a particular gun setting "style" (amount of air / fluid / cone of spray, method of application across the workpece - i.e. speed, direction, sequence, angles, distance of gun from workpiece, etc) to get a perfect result. I had invested in a full pro set-up but was still not getting consistently good results. And was starting to "dread" the finishing part of my woodworking. So the main intention of my post was to encourage others who might be having spraying hassles to get some "expert" hands-on teaching. Once you actually see how it can be done right (and there are probably more ways than one), then you can start to get success and develop your own "expertise". I wouldn't say I'm now an "expert" - but I can see what I was doing wrong and think I'm now "on my way".

But, all that said, good equipment is a bonus. And it has to be maintained - kept clean, particularly the fine pin hole size nozzle openings. (First thing this guy did when he arrived at my shed was take the nozzle off my gun, look carefully at all the fine openings and tell me 6 holes were blocked. I always "clean" my gun & spraying apparatus religiously after using it -by spraying through some thinners etc. So I thought I was OK. But there are 6 VERY small atomising holes on my nozzle and I hadn't noticed they were blocked. It doesn't take much for lacquer to block them. So he very patiently got all the holes clear with a piece of very fine wire. I now know I need to keep the nozzle clean by brushing and "wiring" as well as solvent flushing)

My set-up is a 10 litre pressure pot on rollers with a feed line to a hand gun with in-line filter. Plus wall mounted pressure regulator with water trap. Set up runs about $700. The gun is an Iwata 200 which seems to be the standard pro gun around here. But you can get an Iwata gun and pressure pot set-up (gun & pot attached to each other) which is top quality and MUCH cheaper. I bought all my stuff from Twenty Two Services in Perth. Their factory & offices are in Turnbull St, Neerabup. The technical guru I deal with is Paul Daley (9206 0220). If you're interested give him a call (don't mention the name Richard, he'll probably run off screaming into the distance ... only kidding). They sell all the range of equipment from simpler hand held pots to top of the range 20 litre pressure pots with feed lines, to industrial spraying equipment. They are also the agents for Becker Acroma lacquer. Which is the finish of choice for most of the furniture galleries in the Margaret River area, as well as others I'm familiar with (JahRoc, etc).

But again..... see if you can find someone who is experienced at spraying to give you a quick demo. If you're ever down this way, give a holler.

Richard

I am about to try my hand at spraying my first piece ever with laquer.
New spray gun & compressor, never sprayed before so should be interesting :rolleyes:

Quote:

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Along the way he was explaining the logic behind which surfaces he sprayed in what order, from what direction and what angle (differs for edges, tops, sides, corners, legs, rails, etc etc.).

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If you could expand on the above at all it would be greatly appreciated and educational, especially edges & corners as I am spraying a TV cabinet.

Also if you have any information on pressure settings that would be very helpfull.

Thanks
Gary

Gary, not sure I can do your query justice. Bit like trying to teach someone to ride a bike over the phone. Which is the point I've been trying to get across about lacquer spraying for novices. TRY to get someone experienced to give you a demo of their technique - what works for them (assuming they achieve good results). You CAN learn a fair amount by simple trial & error and reading up on spraying techniques & trouble shooting (there are lots of threads on spraying in this Finishing Forum), but 10 minutes with someone who really knows what they're doing could save you lots of time, money and effort. And frustration and heartache.

But to try to answer your questions (and remember I'm NOT an expert at this. Maybe Neil or Shane or someone who really is experienced can jump in??)...

For tops, do the edges first, moving the gun fairly quickly and probably a little further out ( 250 mm) than for horizontal surfaces (150 - 200 mm). This helps prevent runs. Do one edge then look carefully at the coverage. Good even full coverage with no runs? If yes, you've got enough fluid & air at the speed at which you moved. On to the next edge. If it's splotchy you've gone too fast or not enough fluid. Repeat with fluid dial opened more. (If fluid is running & dripping down the edges you either went too slow or your fluid dial was turned too high). Finish the edges. Then do the top progressing from one side to the other (ie - don't start in the middle & work out to each side). When you've finished one coat, hit it again immediately, exactly the same sequence (ie, dont start where you ended - go back to you're intial surface and go in the same sequence)

For vertical panels, inside the cabinet, do the corner join areas first, then the panel areas between, being carefull not to re-spray immediately right into the corners. Just go slightly into the area already covered when you did your initial vertical corner sprays. This helps prevent too much fluid & hence runs in the corners. Outside - do the same. Swipe down the corners first (pointing the gun so the cone of spray bisects at the corner, then fill in the panels, from one edge to the other, but again allowing for an overlap at the corner so you're not putting too much fluid right onto the corner area from both sides.

This is the same technique for post & rail table leg / base construction.

My air compressor is pre-set at about 110 psi. But the air then goes through a regulator which drops it to about 50 psi for spraying. However, the most important "setting" is the amount of air you allow through your gun. That's controlled by the air valve (usually on the bottom of the gun handle). I'd been throttling my air WAY down. Which resulted in too little air for my fluid setting. Which (along with blocked nozzle holes) created a splotchy orange peel problem. This guru opened the air at the gun way up. Opened the fluid dial about half way. AND MOVED FAST. With that much air and fluid, you need to move fast enough not to get too much fluid in one area. As a guess I'd say he moved at between 1/2 - 1 meters per sec. Faster on the edges and vertical surfaces. We were spraying big surfaces - table tops & bases. For smaller surface areas and confined areas, I'm sure you'd need to dial down the air & fluid. It's all about getting full even coats with no runs (too much fluid) or splotchy dry areas (too little fluid).

Good luck with it.

Richard

i think i will quit while i;m ahead, and stick to french polish , that's easy and looks great, and i just discovered hard shallac, if it's as easy to apply as the normal shallac then that will be what i will use from now on, no equipment required.

Hi Richard,

Firstly, thanks for taking the time to reply in such detail, much appreciated, including the reply to la Huerta, that was also very helpful. When I finish off my next job I will take your advice and then give laquer a go. The finish is worth it I reckon.

Thanks again, and if I get down your way I will buy you a beer.
Cheers
Pops

Hello I will share some of my skill in spraying which I used when I was building kitchens and furniture. This technique was used on a professional level by a few Business' I worked for and I adapted these myself.

Firstly you need at least a 10 cmf Compressor.

The standard spray gun used in the cabinet making industry is the Iwata w77 or wa 77. This spray gun is awesome.

The air out take is set at 60 PSI

I would not use laquer but a thinners based poly utherane which is touch dry in about 5-10 minutes. You will need to try a few brands to see what you like.

Firstly you will need to spray 2 coats of qaulity sealer to suit, sand back and then use the poly ontop.


Always use anti silicone drops in your poly as if there is any silicone tubes opened in your workshop or outside it will cause fish eyes on your work. Before spraying the poly empty the filter from water and at the start of the hose line apply half a bottle cap of metho spray it out of your gun without releasing the poly utherane. This will get rid of any water. Stay about 6-8" away from your work and thats it. Make sure its not cold so you might need to warm the room a little.

I am learning to use oils and waxes as this is not healthy for you or the earth but if I don't get the finishes I seek then I might need to resort to my old method.

I hope this helps.

Joe

Had my first go at spraying Lacquer today, just on some plain'd & sanded boards as this was my first try at spraying anything at all.

60psi at the compressor, 20psi at the gun, Porter Cable HVLP1.

First tried spraying with water to check out the settings on the gun and found I could get good atomisation as low as 8psi at the gun.

Onto the Lacquer....
First tried it straight out of the can, I think it was a bit thick as it left an orange peel type pattern on the wood and did not give even coverage, some areas did not have any lacquer at all.

Thinned @ 10%
A bit better but still seemed to splatter a bit and was not as fine an atomisation as the water.

Thinned @ 25%
Seemed to have good atomisation, played with the spray pattern a bit, left the pattern at where it just gave a narrow oval shape. Not to sure about fluid adjustment, screwed it all the way in and with the trigger pressed in started to back it out, stopped where it seemed to give good atomisation.

Now I tried on some prepared timber:
First coat you could hardly see where it was sprayed. Left 20 min. Felt rough. Sanded lightly with 320.

Second coat you could just start to see a bit of a build of finish but was not even or consistent across the width or length of the board. Left 20 min. Did not feel anywhere near as rough as the first coat. Sanded lightly with 320.

Third coat I applied a bit heavier, moved the gun a bit slower, I moved it too slow on some boards and got quite a heavy wet coat, thought it might run or sag as I was spraying them all upright. Left 20 min. Felt quite smooth. Sanded lightly with 1200.

Last coat I applied normal speed but went back and forth over the boards until it looked wet all over when held up to the light at an angle. left 20 min. Felt quite smooth.

Conclusion:
Even though I applied the lacquer quite heavily in places I never got any runs or sags. On top of some knots the lacquer seemed to pool around it and not cover the knot itself, I applied several extra coats to these spots and eventually covered them, very wet coats but still did not run or sag.

I think I will do some more test spraying next weekend before attempting my first real project that is built and ready for staining finishing.

Happy spraying.

Gazza, you're on your way. Good to hear.

Were you spraying onto flat / horizontal test pieces? I've found you can go pretty slowly and get a very wet finish, without runs. Unfortunately, with vertical surfaces & edges, you'll get runs if you go too slowly or have too much fluid. Or spray too close. I usually back off a little on edges as opposed to horizontal surfaces. And go a little faster. Another trick with edges is to give them a couple of hits, allowing a little time (30 - 60 seconds) between hits.

Regarding orange peel / incomplete coverage, in my case I learned I wasn't getting a good even full coat because I was airing down my gun too much. The guru I had give me a demo turned the air way up, increased the fluid a little, and got a perfectly even coat. But he did move faster across the workpiece.

Let us know how the next spray goes,

Richard

Well, finally got the courage up yesterday to have a go at spraying the completed centrepiece of the unit.

In summary:
Not as good a finish as I would have liked, BUT I am happy with my first attempt at spraying something for real. A bit of "Orange Peel" here and there, not consistent coverage, but I guess you get all that with experience. I think I was to scared of getting runs and didn't thin the Lacquer enough, which in hindsite did not give full coverage so I opened the material flow a little without increasing the air flow or fan spread which I think added to the "Orange Peel" problem.

It is easy to sit back after the fact and think I should have done this or that but at the time without experience it is hard to know what to do while in the act of spraying.

I have started to compile a "Common problems" chart that I can have handy while spraying and refer to that.

For instance I have searched the net and found out that I could have tried the following:
1. Thinned lacquer more
2. Reduced the flow of material
3. Increased the Fan spread without touching anything else.

I actually increased the material flow and reduced the fan spread, the exact opposite !!!

Well, still got the two side units to spray so more practice I suppose.

I sprayed a couple of drawers and found I got a LOT of blowback when spraying into the corners, I am glad I left the back off of the centre unit.

Equipment:
Porta Cable HVLP gun
Carbatec Belt driven Compressor
Lacquer thinnned 25%
75psi at compressor, 20psi at gun

Gazza, I'm wondering if you had enough air through the gun? My orange peel was caused by too little air for the fluid, so I was not getting good atomisation, but rather a "droplet" effect. Also, my guru kept a full fan cone going. Even on edges. So for him it was lots of air, a fair amount of fluid. And confident fast spraying.

If you're not happy with the finish, just lightly sand with 320 and hit it again. That's the nice part about lacquer. It's not a huge drama to do a light sand and another coat.

Richard

Gazza,


One thing I have noticed when spraying lacquers is that the finish can change over the first week or so.

I have had orange peel type finishes flatten out over 3-7 days. Just becuase it feels dry doesnt means its really dry.

Someone told me once if you can smell the lacquer it hasnt fully cured becuase its still off-gasing and setting up, not sure how true that is though.

Joe