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Ravens53
Spraying water based Polyurethane

I just finished a sunroom with Birch tongue and groove paneling.
I want to spray a clear water base poly as it does not yellow as much as oil base.
I am using a HPLV air gun.
Does this need to be thinned and if it does what shall i cut it with? :confused:

JLMCDANIEL
Re: Spraying water based Polyurethane

You thin it with water if needed. Some polys need to be thined others don't. Wipe on poly is usually thin enough.
Jack

Re: Spraying water based Polyurethane

Thanks all!!! this weekend I am going to give it a try.:eek: I'll have pictures;)

canuk
Re: Spraying water based Polyurethane

You might need to check the viscousity of the material to be sprayed. Usually sprayers will have a spec as to the viscousity value.
Check this link : http://ronjoseph.com/Q&A/B1503_zahn_cup.htm

A. Spruce
Re: Spraying water based Polyurethane

When applying poly by brush, it is thinned so that it is absorbed deeper into the wood for a stronger bond and longer lasting finish. While you may not need to thin the material for spraying purposes, I'd be inclined to do it for penetrative purposes. The polys I've used are usually thinned 25-50% for the first coat or two, then applied at full strength.

Side note: STAY AWAY FROM MINWAX POLYS!!!!!! They do nothing but bubble and foam, and I'd suspect that spray application won't help matters any. Both McKloskies and General Finishes make an excellent poly.

JLMCDANIEL
Re: Spraying water based Polyurethane

If you are going to use a water based product you should raise the grain before you sand.
One reason to thin the WB poly is that it is so fast drying. Thinning helps prevent the droplets from forming a skin on their surface so they end up as a surface coat. I'm sure you've all seen furniture that you can run your thumb nail across and scrap off the finish.
Jack

Re: Spraying water based Polyurethane

I am using water base poly as I have been told it does not yellow as much as a oil base poly.
There is a viscosity stick with the sprayer.

I am going to use a pratice piece first.

I thought I would run it past some people that have personally done this before. As I never believe all that you read they always make it more simple than it really is. I have a lot of time in this project and do not want it ruined by a poor finish.
It is a 14 X 14 sunroom with a raised ceiling all tounge grove variegated birch various width boards. I'll post pictures when I am done. I hope it does well:eek:

canuk
Re: Spraying water based Polyurethane

Harry ... good luck ... I'm sure you'll do a good job.;)

Re: Spraying water based Polyurethane

Just a update on my first time using a HPLV spray gun. I bought Varathane water based Satin Polyurethane. I tested the poly for the proper viscosity loaded up the gun with the thin aplication needle. I have so far used two gallons in two coats and it looks like I will need 2 more but the resualts are what I had hoped for. Here is the picture of the room before I sprayed. I had to make some corner blocks as I had three pieces of crown molding that came together at one spot.
I hope to be done by wednesday and in few weeks when I am done I shall have pictures

canuk
Re: Spraying water based Polyurethane

What?!?!? .... You're not done yet ?????:D

Nice job .... not bad for a sparky.:D:p:D

Re: Spraying water based Polyurethane

[QUOTE=canuk]What?!?!? .... You're not done yet ?????:D

Nice job .... not bad for a sparky.:D:p:D[/QUOTE

To funny.....I have been on the road all week long in Illinois and Wisconsin. I got home friday night at 8 pm. I was up at 8am and worked till 11 I had a graduation... Gees work sunday doing exspence reports and paper work. The sprayed a second coat today at noon. I want some rest...... Yea not bad for a old sparkey lol
I guess I deserve to get my B*lls busted cause I give you a hard time to lol

What did you do up Nort this weekend? To funny:)

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