laquer,shellac or poly? - Woodworking Talk

~WoodChuck~ · 02-28-2009, 09:22 AM

I am no finishing expert my no means but whenever i finish a piece all i do is use a oil based poly to it. It seems like there are better options out there but my lack of information on these products always leans my toward poly. I see things out there that look like a glass finish and are really smooth but my stuff doesn't always look like that. I dont have a spray gun yet but am looking into buying one. So what is the difference between the different finishes, what are there applications, and how are they applied.

mwhafner · 02-28-2009, 01:07 PM

I think the intended use of the piece dictates the finish, to a degree. I like the look of shellac, as it adds a little more depth to the finish, but is not as durable.

Lacquer is easy to work with, and dries very quickly. It is also more durable than shellac.

I don't use poly unless the intended use of the piece calls for it.

johnnie52 · 02-28-2009, 02:57 PM

First of all, you do not need a spray gun and all that goes with it (compressor, dryer, gauges, etc.) to have a really great looking finish. Its nice to have, but can be expensive for just a few pieces. Get yourself a good natural hair brush.

Make sure that you have done your sanding of the raw wood before applying any finish. Depending on what wood I'm using, I start with 100 grit and work through to 220 grit. Then I either apply a sanding sealer, or simply mist the piece with water to cause any fibers to rise and sand again.

Poly is my preferred finish. I brush on oil based and use a roller with one of those sponge type heads with water based. Always sand between coats to give the fresh layer something to adhere to.

I've just finished a project using shellac. It was my first experience using this type of finish and I was surprised with the results. Shellac is not very resistant to scratches, spills, or abuse. So I would not recommend it for table tops that are going to see heavy use. However, it comes in several different colors and can be touched up very easily. If all you want is a clear coat.... they got that too. It dries fast and several coats can be applied in a few hours. It doesn't require a lot of between coat sanding because the new coat actually melts into the old coat.

I've never tried to use lacquer on wood, only on car bodies. I have heard both good and bad about it. I know that on metal panels if its good its very good, but if you screw up its awful! The trick is to spray light coats and sand throughly between coats. It drys quickly and is actually the only one of the three that should be sprayed rather than brushed.

Regardless of the finish you choose, you're going to have to rub out the last coat to get that glass smooth finish. I do this using 600 grit wet/dry paper. Wet the paper using soapy water and sand with the grain. Use your fingers to "feel" the surface as you work and stop when you get to what you want. Don't get carried away or you can cause the finish to be blotchy. Finishing up with a couple of coats of good quality paste wax is optional.

Go wash your car, then wax one fender with paste wax. You'll soon be waxing everything that will stand still long enough.

CivilEngineer13 · 02-28-2009, 06:46 PM

If you want the have-all, end-all to finishing. Read Bob Flexner's book: Understanding Wood Finishing. Trust me, you won't regret it!

Joe Kobylski · 02-28-2009, 08:29 PM

I disagree about the compressor and spray guns ,aman old guy and have always done things by hand, but with arther kicking in I bought a graco and pot. when doing my work by hand I always sanded with a 320 grit paper for my first coat, then I thined the first coat by 25% with mineral spirits this will give it more drying time and allow the bubbles to break down and less sanding between coats also lets it flow more evenly.before putting on second coat would sand very lightly with 400 paper and wipe with mineral spirits to remove any residue.then put on second coat without thinning. then wet sand with 600 paper and buff. another clue is never use high gloss poly unless you are really good as its harder to work with , semi gloss and then satin is even easier. I us e almost the same proceedure with my new spray outfit except have found practically don't need any sanding between coats and have a much glossier appearance and jobs that used to take 4 hours to hand poly am done in about 30 min.

GeorgeC · 03-01-2009, 08:33 AM

The only thing I have ever used on wood (or a car body) is lacquer. I find it durable, very forgiving to work with provides a very nice finish.

I have never done anything but spray. Of course I purchased my first air compressor 40 years ago. I cannot imagine a shop without a compressor. The fact that I was into automobile work long before wood working may have something to do with that preference.

You do not have to purchase a large or expensive compressor to accomplish most tasks. Two years ago when I was refurbishing a rental condo I bought a 1.25 hp Craftsman, 3 gallon compressor. (As a Craftsman Club member I think I paid $89 for it.) Now days I find myself using that more than my 30 gal 5hp compressor. Of course it will not work with tools that require high air volume such as impact tools and sanders. It does very well with the small paint gun I use to spray lacquer.

George

mwhafner · 03-01-2009, 10:10 AM

If you are looking at spray systems, check out this - http://www.rockler.com/product.cfm?page=10469
While it is not a Turbinaire, it does a great job with lacquers, or a fraction of the cost. They will occasionally run it on sale for $89.

The woodsman · 03-01-2009, 10:48 PM

If you want to go with a spray gun,go with a gravity feed as you don't need a lot of air and you have a lot less over spray an fumes floatin around.

mwhafner · 03-02-2009, 12:55 AM

I have a couple of gravity feed guns, and would take the self-contained unit linked above over them. I have almost no overspray, and the air unit provides plenty of air.

If you are looking to use an just a spray gun on a existing compressor, then go for a gravity feed gun. They do work better in most circumstances than siphon feed guns.

scribbles · 03-02-2009, 01:51 AM

Shellac = medium drying, very easy to apply, will cover anything, warm color, high gloss, Very weak gets eaten by alcohol, water / weather will age. Recoat time 1.5-2hours

Waterborne Polly = medium drying, no fumes, medium strength. Very susceptible to contamination= fisheye, or alligator. Recoat time 1.5-2 hours

Oil based Polly = slow drying, mild fumes, great flow out, Not very susceptible to contamination, good for exterior application, most uv stable, may washout color. Recoat time 5-9 hours.

Lacquer = Fast drying, strong fumes, good flow out, low contamination, good for Interior projects, can be tinted, not good for exterior, medium hardness after 30 days, recoat time 15-30min.

Conversion Varnish = dries like lacquer, hardness of Polly. Very susceptible to contamination.

Pick a sprayer, only way to topcoat.

Tony B · 03-02-2009, 03:06 AM

10 to 15 minutes between coats. That means you can actually completely finish a table or a dresser in an hour with 4 coats.

Lacquer looks like glass, Poly looks like plastic.

A good quality furniture lacquer is probably the most durable finish.

scribbles · 03-02-2009, 11:50 AM

The only time I do not to use lacquer is outside, or if a customer had reactions, or allergy's to the chemical.