polyurethene: sanding, nibs & thinnnnning

[John Moorhead]

Folks -

Ok, okay..... she had her pick of a dozen stains, dyes & shellacs for a solid oak Shaker Cradle.... and the choice is Natural Tone Satin Polyurethene... So, that's that...

I am prefinishing the red oak before I cut and assemble, in a bid to get a smoother finish. A Couple of questions have crept up on me:

1) Even though I am brushing the finish on the boards in a fairly warm room, the finish is rather thick. I would * really* like to thin it with paint thinner ~ 5% by volume to improve levelling. Would this be good practice? What kind of trouble can I get into?

2) Nibs - I got 'em! I expect that I'll wet sand with thinner and a sanding block for better flatness than I might get with steel wool. What grit should I use?

3) I have started with 2 coats and will let it dry in a warm location for 2-3 days before I sand - any tips for the final applications of poly? I should expect to do some finish sanding, no?

4) I'd like to tape off the areas that will be glued - is blue painter's tape up to the task if I am careful about finishing near the tape line?

TIA for your remarks...

John Moorhead

[J T]

Mon, Dec 13, 2004, 6:52am (EST+5) [e-mail] (John=A0Moorhead) asks: 1) Even though I am brushing the finish on the boards in a fairly warm room, the finish is rather thick. I would * really* like to thin it with paint thinner ~ 5% by volume to improve levelling. Would this be good practice? What kind of trouble can I get into?

Ah, I've got this part covered. If you're right handed, hold your left hand up in front of you, and vice versa. Cup your hand, with your fingers point up, and stand the can on your fingers, front of the can facing you. Stare at it for 5-10 seconds. Then, slowly, use your other hand, and turn the can so the front of the can is now facing away from you. Now, slowly read the back of the can. It should tell you what to thin with. Additionally, there should be a 1-800 number that you can use to call the manufacturer, and ask them questions.

JOAT We cannot direct the wind, but we can adjust the sails.

- unknown

[John Moorhead]

JT -

Well, yes... Of course I read the directions... I was asking for personal experience of those on the board in addition to the MFR's instructions that may well have been vetted by a bunch of Lawyers rather than experienced woodworkers.... My bad!

I'll bet you're also the only guy that drives 55.0 in a 55 zone too.... Ah yes, as Mark Twain said, virtue is its' own punishment.

Thanks SO much for the advice!

John

[J T]

Mon, Dec 13, 2004, 8:35pm (EST+5) [e-mail] (John=A0Moorhead) now says: JT - Well, yes... Of course I read the directions... I was asking for personal experience of those on the board in addition to the MFR's instructions that may well have been vetted by a bunch of Lawyers rather than experienced woodworkers.... My bad! I'll bet you're also the only guy that drives 55.0 in a 55 zone too.... Ah yes, as Mark Twain said, virtue is its' own punishment. Thanks SO much for the advice!

Ah, new input. Well, you didn't say you read the instructions, and so many people don't. But, that being the case, if it was me, first thing I'd do would be call and ask what the manufacturer's people have to say. Then I'd probably just go aheat, thin it, then try it out on some scrap. Different manufacturers, probably slight different results, that way you've got first hand experience. By the way, kerosene works, but takes longer to dry.

Depends. If i've got some guy right on my bumper, sometimes I do. Other times, usually depends on the traffic flow. But, as I'm usually not in any great rush to get anywhere, 55 is usually good for me. On a real nice day, and no traffic behind me, might just do 45.

You're welcome.

JOAT We cannot direct the wind, but we can adjust the sails.

- unknown

[Mike Myers]

I normaly sand with 220 grit, dampen the wood and let it dry. Sand again lightly with 220 or higher just enough to remove the nibs. I have been thining Minwax Polys about 25% and applying as a wipe on. Usually takes 3 to 5 coats. Sometimes I add BLO to the first and second coat. Lightly sand or steelwool between coats as needed. I also prefinish parts before assembling when they are hard to get at.

Mike

[sandman]

A woodster in Rochest NY suggested once that I should try this:

30% thinned MinWax Poly. He called it a 'piss coat'. Soaks in realllly deep. Thinned with Varsol. Remove the fur (his words) after 3 days with 220. Do it again. Next two coats thinned just enough to level the brush marks. sand in between with 320. Then when all is dried and hardened, 0000 steelwool loaded with Trewax, Carnuba. Clean and buff.

Looks as good as Clarke's Catalyzed laquer from an HVLP in an electrostatic downdraft booth.

Nay...BETTER!

I tried this on cherry (is there another wood?) and maple.

*I* like the results, but it's so personal.

Rob.

"Dynamite With A Laserbeam"