Finish application. Polyurethane, Varnishes.

[William Frederick]

Which is the best way to apply finsihes? Brush or Spray?

 

I applied the stain and am working on applying my clear coat. I have been using a brush with water based polyurethane, thin coats and sanding and steel wool in between coats. This seems fine but notice some brush marks. Thought that spraying might be better but did not know if there is other problems associated with that.

 

Any input would be helpful.

 

Thanks Bill

[Robert J Guidry Sr]

This is my prefrence only, I am sure others will disagree with me, but I would and do spray all my work. I hate brushing because no matter how hard I try, I always see brush strokes. I have sprayed a number of finishes including but not limited to oil base and water base poly, water and oil based paints, etc. Poly sprays well without much overspray because the viscosity is thin and you can cut down the pressure to reduce the overspray. Paints are a little harder because they are thicker and require much thinning to reduce the viscosity and usually require an extra coat to cover. I use a conventional spray gun to do this. Have not used HVLP spray guns, because when I looked into them the feed back on most sites was bad on the cheaper systems and I cannot spring the money for the more expensive units.

[Jeffrey Pike]

Instead of steel wool, take a spray bottle filled with water and spray the project then use a 400 grit wet/dry sand paper U R going to get a white type of slurry then spray the project down again and wipe off with a clean paper towel and repeat I do this 3 times. I also use a hvlp spray gun, the key to a good finish is keep the gun about 12 inches away and a good sweeping motion and thin coats and get a good hvlp spray gun if U can't get a good spay gun then I would try a better brush. I use a china brisle brush that works well ora try a sponge brush they worak ok too

[Jim Carroll]

Spraying is the way to go but has a steep learning curve.

I prefer a gravity fed spray gun with a regulator on the gun, do not rely on the regulator on the compressor.Also get a good filter on the compresor to keep the water out. 2mm nozzle will do most jobs.

Make sure to filter the paint or what ever you are spraying to avoid cloging or impurities getting through the gun.

[Kim C]

I have always been told never to use steel wool when using anything water based. As microscopic "fibers" will rust in the finish if missed when wiping up. I have just always avoided steel wool altogether. Wet or dry sandpaper has been my choice. I also use oil based everything most of the time. Not sure why I have stuck with that for so long but I like it. Not made the jump to spraying yet because I really enjoy the hands on of brushing or rubbing on stain/finish. But have considered it so I am watching replies to this thread for info as well!

[Don Husslein]

I totally agree with Kim C ... NEVER use steel wool with anything water based. If you don't really want to spray, have you tried one of those sponge brushes? Another option, try using wipe-on poly - it's a bit thinner. I've also used Jeffery Pike's method of using 400 grit. I've even gone so far as to use 800 grit with excellent results. I really should get a sprayer - but need so many other things first.

[Jerry Lee]

I agree with Robert,but I like the HVLP gravity feed guns.You can pickup up one that will work fine on small projects for about $40 bucks at Lowes.Be sure and install a water separator in the line before the Gun.You can adjust pressure as needed.I personally hate Brushing because I used alot of sanding sealer before I apply my finish coat which is usally Laquer and if you brush it you will surely have runs.As far as the steel wool I would leave it alone on water based products(Rust). You might try the aerosol cans of poly they work great .Thanks

Don Husslein said:

I totally agree with Kim C ... NEVER use steel wool with anything water based. If you don't really want to spray, have you tried one of those sponge brushes? Another option, try using wipe-on poly - it's a bit thinner. I've also used Jeffery Pike's method of using 400 grit. I've even gone so far as to use 800 grit with excellent results. I really should get a sprayer - but need so many other things first.

[William Frederick]

I want to thank everyone for their input. It is much apprecatited!

I did decide to get a spray gun. Bought a gravity fed gun from Lowes ($38). My first attempt was not too bad. But did require some good sanding. I would also agree there is a learning curve. (I guess that is why I started on a small end table so I could learn some of these things before I try a coffee table or something bigger.)

I will put the extra regulator in between the compressor and the gun. I think that this is a good idea and will help stabilize the air pressure some. I noticed everytime I set it at the compressor it seemed to be high then fall and basically up and down. I will also try to turn down the air pressure to 20 - 25 psi. I am sure I had it a little high (35-40 PSI and foggy).

I never thought about the steel wool and water based products causing problems, but this makes sense. I will go to Lowes and get some 400 and some 600 grit sandpaper. I have some 220 and some 800. This will let me work it down in proper steps without using the steel wool. This seems alot like finishing paint on a car. You would wet sand and buff it out. Has anyone tried using the scotchbrite pads? Just a thought. I know they come in different grits and we use them in metal work.

I like the waterbased poly because of cleanup. I do not need any chemicals, just soap and water.

I will keep at it until I get the look I want or my hands get sore from sanding. I will post pictures of the finished project soon.

Thanks again

Bill

[Jeffrey Pike]

The other thing is water based poly is not a harder finish than regular oil base poly just throwing out their

[T Corey]

Hi Bill: I also use a HVLP gun. I have several. I have two that are around $250.00 a piece. The one I use 99% of the time is a Porter Cable. It was about $60.00 and it works just as good as the higher priced guns. I have painted cars, boats, tractors, used water based poly on all the interior doors and trim in the houses we work on and all my woodworking projects with the Porter Cable. I just make sure its clean when I'm done and it has never failed to perform, plus if I ever have a problem with it I'll just replace it since it's a cheaper gun. When I spray poly I spray It straight and put on 2,3 or4 coats with some light sanding between and they come out really nice. Just takes some practice to get the right pressures and patterns. Sometimes I have problems with water from the compressor, even with the water separators, so I always drain the water from it several times while i'm spraying just to make sure. I put the poly on as heavy as I can without runs and I go across the grain on the first pass and with the grain on the second pass. So if I was putting on 3 coats it would actually be 6. Works for me. I know everyone has there own ways. Just my two cents. Good Luck! T

[Hugh Clare]

My grandfather was a painter/furniture refinisher. I didn't have sufficient interest to learn much from him when he was alive, but I do remember him chastising me for "dry brushing". It has become clear to me in recent years that even with poly, a dry brush is your enemy. Whatever the finish material, there has to be enough of it there to flow together. I have Grandpa's spray equipment, and have even considered an HVLP sprayer. I just think there's a richness to a brushed finish that can't be achieved with a spray. I've tried water-based poly and am not impressed. I think it's important to wet-sand between coats, as well.

[David Parker]

I prefer spraying, you can get a cheap digital regulator at Harbor Freight for 15.00 that mounts to the gun. They also sell a pretty good filter setup that mounts near the compressor, about 28.00 on sale. Its the one with a large round single body with a drain port on the bottom. Don't buy the cheap one with two drain cups, they don't seal, very frustrating. I also buy cheap filters that fit right onto the digital regulator. Most woodworking stores sell grey 3M pads, they work great for in between coats. Then I take a tack cloth to clean up everything and lay down another coat. For automotive finishes, I use wet papers all the way up to 3000 grit.

David

Hope I don't get in trouble posting links.............. Just trying to help.....................

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