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View Full Version : Is a clear coat necessary after stain


StrategicReef
11/13/2007, 12:35 AM
I wanted to know after staining plywood is it required to use some kind of polyurethane all not? I have the oceanic stands that is built with plywood in a cherry stain finish I think they don't have a clear coat on them but they are holding up OK. Because I can stain things pretty nice but not sure if I can do a good job brushing varnish/lacquer/polyurethane.

iairj84
11/13/2007, 12:38 AM
They have spray on polyurethane that works really well and goes on evenly. It's a little more expensive that the brush on, but it works better IMO. If you can spray paint evenly then you can do this. You might use some really fine grit (500 or so) sandpaper between coats and do two or three for a great finish.... I don't think the Poly is totally necessary it just helps A LOT if you get water spills and what not... At least in my experience.

hllywd
11/13/2007, 09:08 AM
Personally I'd say it's necessary to put a seal coat or two on. The first coat will probably soak in some and not look as good as you'd like and will probably raise some wood fibers making the surface a little rough. Sand between coats to remove and raised fibers, tack all the dust off, and apply the final coat, or repeat the process for as many coats as you'd like.

If you can stain with good results you can put the polyurethane on too. I would reccomend a water based finish applied with a foam brush. Make sure you keep a wet edge as you progress and it's easy. Water based makes a very durable finish with low odor and easy cleanup.

iairj84's spray bomb idea would work too but I find it more difficult to make it look even over large areas. I have an HVLP spray system on the other hand that will lay a coat of production laquer on like a layer of glass. Maybe you know somebody or there's a local cabinet shop where you could have it done reasonably...



Tim:cool:

custommike
11/13/2007, 11:36 AM
especially with a salt water aquarium. you can guarantee that the water will mess up your finish without it being sealed. its easy and you will be much happier with the end result. stain is not really a finish, its just that a stain. leaving it unfinished will leave it open other chemicals staining it also. P.S. I worked in a custom wood shop where we finished all our stuff for several years.

Sk8r
11/13/2007, 11:56 AM
Be very, very careful when applying: ventilate, and use a chemical mask. THis combination killed a relative of mine.

hyperfocal
11/13/2007, 02:46 PM
Which combination, Sk8r? Urethane on top of stain?

rickh
11/14/2007, 03:18 PM
The wood absorbed the stain--it will do the same with water. Coat every surface with polyurethane--especially the inside of the stand. R

BeanAnimal
11/14/2007, 04:32 PM
Some "stains" contain urethanes, but for wet areas I would recomend a good quality top coat urethane.

Sk8r
11/14/2007, 04:36 PM
It was Olympic stain, combined with a Bear topcoat, I think---not sure of the second product, but it was a clear seal. The sensation was one of burning all over the skin---not the lungs; but it was the lungs that ultimately got it. The stuff pervaded the house and the respiratory damage occurred within 24 hours. Ultimately fatal. Nasty stuff. Just be sure to ventilate, even during the drying period.

BeanAnimal
11/14/2007, 04:45 PM
Sounds like he was alergic to some of the organics.

StrategicReef
11/14/2007, 04:48 PM
I was told most of the common respirators do not stop isocynanites in the polyurethane anyway?

BeanAnimal
11/14/2007, 04:54 PM
A common "paper" respirator will not. You need one that is chemical rated.

Most of what you smell with polyurethane coatings is the petroleum based organic materials and other modifiers. There really is not a lot of iso there.

Paint and basic polyurethane coatings do not bother me. However, I have pumped millions of pounds of raw plural component polyurethanes. 1:1 diisocyanate and polyol. I am now alergic to it (I suppose due to over exposure). Nasty stuff. If I get it on my skin it causes a rash...