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Eric Baird
01-11-2016, 2:00 PM
Hey guys this is my first post and I’ve got a situation.
I am attempting to start a woodworking business including building ornamental redwood planters in geometric shapes and have streamlined my processes but the finishing has got me scratching my head.
I have gotten set up to spray and am running a small 8 gallon compressor with a cheap gravity fed gun that works pretty good in my opinion -will work better with practice of course. After researching the fastest way to apply a good finish without sanding between coats, I decided to start with spraying Deft brushing lacquer since spraying lacquer is either really hard to find in the Bay Area or really expensive. I found 1 source -Kelly Moore, and wasn’t willing to pay ~60$ a gallon to experiment. Even Deft is only available at some big box stores and not others although that is due to it’s parent company being a competitor. It should be noted that these are decorative indoor pieces that hold plants that don’t require soil so the moisture/ UV protection shouldn’t be a big deal.
Anyway I tried spraying redwood sanded to 150 grit with Deft thinned with acetone around 50/50. I’ve read the fast drying active solvent will kind of offset the slower ones added to make it brushable and it would dry faster. Plus I’ve also read multiple thinner coats give a better end finish. Later I read (lota research) thinned lacquer can be it’s own sealer. So this seemed a good idea to me.
The lacquer built up on the denser rings and totally soaked into the spongy soft wood between. It looks like shiny tiger stripes. Which is kinda cool looking, but not what I am after. I want to build a uniform gloss base and then do my topcoat in satin or semi-gloss. I applied many coats, probably 5 or 6, and the big contrast in sheen was still there.
Then yesterday I realized I may have just applied a sealcoat and that subsequent coats would build more evenly. So I lightly scuff sanded and sprayed straight unthinned Deft on thicker than the thinned coats. Only got one coat on before it started raining.. The stripes were still there when it dried, although the softwood areas were a little bit more shiny. Going to spray unthinned again today.
SO my questions are: Is this just going to take a bunch of thick coats and having to sand down the areas that have built up more? Is there a thicker finish I have overlooked that drys fast and can be applied in fewer coats and more evenly soak into different densities of grain? Since I plan to switch to water based acrylic lacquer (fumes/ being able to spray inside/ almost same working qualities) does this problem occur with most or all finish types?
It’s pretty frustrating cause I can’t make what I make look like what I want. Any help would be appreciated. I am going for quality and speed of finish.

Scott Holmes
01-11-2016, 3:00 PM
Lacquer is pretty low on solids you will need many coats. Have you thought about spraying a waterborne finish?

Eric Baird
01-11-2016, 5:17 PM
I just sprayed and sprayed unthinned thick coats and it is STILL not building evenly. NC lacquer is just not the best for soft wood I guess.
The soft areas ARE building a film just much more slowly than the dense rings. I believe since I will do a top coat of satin that the sheen contrast will be balanced in the end.
I do plan on switching to water based acrylic "lacquer" and have been reading good reviews about Target EM6000, although the cheapest option allowing burn-in and fast drying will probably be what I go with. Is a water borne lacquer inherently thicker than NC so it wouldn't soak in as much in my case? I assume the solvents in NC allow it to penetrate more deeply in spongy wood before in dries -especially a brushing NC with slower solvents.
Also would the EM7000 high build version be even better? Is the 6000 just lower solids so one could spray more thin coats?

Eric Baird
01-12-2016, 7:36 PM
Although I only got one opinion on this matter, I thought I would share my experience so as to help anyone who may have a similar issue and find this through a search.

I got a can of Deft satin and sprayed it over the coats of gloss and that really helped even out the balance of sheen (as well as hide my mistakes a little better). The contrast in shine was still just barely there and the rings that had built up finish were just that- built up more. I could have sanded them even but I am happy with the way it turned out.

Something I noticed is that the satin, even one coat over a gloss base, did mute the color of the redwood a bit but in this case the outcome was better than the situation with the glossy stripes.

The biggest factor though, that I hadn't really thought of before, is the sanding grit. I only sanded these to 150, because that is the grit on my homemade disc sander and from my research 150-220 is usually acceptable as a smooth enough base for a clear coat. I should have gone at least to 220 -especially for softwood. The rougher grit sanding had given an already spongy softwood more surface area to soak up more finish and scatter more light, not showing the gloss that the harder rings directly adjacent had. These planks had been planed before they were cut but had sat around outside and gone brown so I gave them a quick ride on the 20" disc sander before assembling. I know now the density of the wood species and what grit you sand to are related and can affect the appearance of the finish.

I am hoping when I switch to water based acrylic finish the higher amount of solids and lack of solvents will allow it to sit on and not in the wood as much, as I do work primarily with redwood.

Allan Speers
01-12-2016, 8:26 PM
Off the top of my head, and me not being an expert by any means-

I'd try starting with a few sealer coats of super-blonde shellac. Then do the nitro.

As for the nitro, I've personally had a BAD experience with Deft. - As in "never again!" It may be "pure nitro" but it isn't pure liquid. It contains a lot of tiny solids, which I guess are meant to build up the pores. However, once you have a flat surface, further coats look like dung. I found it basically impossible to get a glass-like finish. (working on guitars)

Michelle Rich
01-13-2016, 5:57 AM
I must be confused here..redwood is THE outdoor wood..the finishes you are trying do not appear to be for outdoors..they will go bad very quickly..what about an outdoor oil? easy, fast..once sold, people can refresh themselves..

Eric Baird
01-13-2016, 11:59 AM
I must be confused here..redwood is THE outdoor wood..the finishes you are trying do not appear to be for outdoors..they will go bad very quickly..what about an outdoor oil? easy, fast..once sold, people can refresh themselves..

After researching the fastest way to apply a good finish without sanding between coats, I decided to start with spraying Deft brushing lacquer ..... It should be noted that these are decorative indoor pieces that hold plants that don’t require soil so the moisture/ UV protection shouldn’t be a big deal.
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I'd try starting with a few sealer coats of super-blonde shellac. Then do the nitro.
I have read shellac is a good universal sealer and may work better than a few coats of thinned NC. I will look into that further next time.