On Thursday, January 2, 2014 8:30:31 AM UTC-6, HerHusband wrote:


5. Let the first coat of poly dry overnight, then sand lightly with 220

grit. Don't get crazy and sand through to the stain, you're just trying

to knock off all the little dust nibs that settle in the finish. The

clear finish will usually look dull and white after sanding. Then use the

shop vac brush to clean up any dust on the surface.

At this point you should advise those that are seeking advice to read the directions on their specific brand of poly for its application. Generic instructions won't serve well for all brands of poly. Some have recoat times of 12 hours, some 8, and some are as little as 2 to 4.

Failure to follow the specific instructions of the manufacturer can lead to lack of adhesion, witness lines and a list of other problems.


6. Apply a second coat of poly. Let it dry overnight, then lightly sand

with 220 grit again. Shop vac the dust again.

See above for recoat times.


7. Apply a third coat of poly. Let it dry overnight before handling.

See above for application timing.


I normally use oil based polyurethanes. However, they have a strong odor

and dry slowly (more dust gets trapped in the finish). Sometimes the oil

based poly tends to act as a solvent and picks up some of the stain.

Also, projects that I have finished with oil based poly can have a strong

smell for a couple weeks. This is more noticeable with projects that are

closed up like drawers and cabinets.



I am currently trying the water based Min-Wax brand polyurethane, over

the General Finish gel stain. So far I've been rather impressed. It

brushes on nicely, has virtually no odor, and dries quickly. I didn't

notice any of the stain being pulled up like the oil based poly does, and

there's practically no dust nibs in the finish since it dries so fast.

Otherwise, I'm using the same three coat method I normally use.

Read those instructions! I do a fair amount of finishing professionally through my contracting company and I have never found it wise to work outside the parameters and instructive directions given by the manufacturer.

For example:

With Minwax oil poly, Minwax specifically says a 2 hr recoat:
http://goo.gl/fV6Rzu

For Minwax waterborne poly, Minwax states 2 hr recoat as well:
http://goo.gl/SRrhGS

These are a world apart from the oil based GF finishes you reference. And when discussing waterborne finishes, overnight is simply too long. Take a look at the Varathane site which also says 2 hrs. to recoat:

http://www.rustoleumibg.com/images/t...lyurethane.pdf

Sherwin Williams waterborne poly is a ONE hr recoat:
http://www.sherwin-williams.com/docu.../035777464212/

You get the idea. Many other manufacturers have their own times for recoats and their application. One should completely familiarize themselves with the product they are using before they apply it to their prized wood working project. Giving advice in an off handed way can ruin projects for the folks that read these messages and follow their instructions...

Robert