My stair tread project is on its way.
I put 3 coats of poly on and will sand after 24 hours to continue to put more coats on. (its a minimum of 4 coat project, and does not ask for sanding until a coat has been dry for 24 hours and i ran out of time today)
I plan to lightly sand with 220. It is water based poly. Should i just blow it off with a compressor or use a tack cloth? does it need to be spotless to add more coats
Ive seen some products say you dont even need to sand the powder because it will blend back in with the next coat but I dont just plan on leaving the dust and i dont remember which product i read that on
what will a tack cloth do? can it damage anything? do i need it?
these are reclaimed fir stair treads with knots and wont be a super smooth finished look.
I plan on doing 7 or 8 coats of poly for a thick hard finish. (why?)
1- i had to buy a gallon and will have no other use for it so i might as well use it
2- these are stairs treads and i dont want to redo it down the road. the top may fade but i can take the tread out, sand it, and recoat if needed
3- this is varathane high traffic floor finish and not a commercial floor product so i dont trust that the minimum 4 coats will be enough ((and i dont trust that my coat will be enough, enough, or too much)
4- i will be using 4 to 5 coats of gloss then switching to satin for the final 2 coats
Replies
A 'tack cloth' in the traditional sense is a cloth (usually cheesecloth) impregnated with a solvent based substance or mixture of solvent based substances such as turpentine, mineral spirits, etc. If you are using a water based finish, such as the poly you mention, you would not need to 'tack' the surface between coats with a traditional tack cloth. A clean cloth dampened with water would be sufficient to wipe away any residual dust. Using a tack cloth would likely leave behind some oil based residue that may not be compatible with your subsequent coats of water based poly and present some problems with the finish.
I've been woodworking for over 35 years, and never used a tack cloth.
7 or 8 coats is a lot. I'd use maybe 4.
thanks john. The product is a minimum of 4 and after talking to them and searching around I thought a few more wouldnt hurt. Mostly because this is stair traffic, for having to buy the whole gallon, and at the risk that i may not be using enough per coat to meet their minimum. i really just dont want to do it again.
I also wanted to do the 4 coats in gloss and then finish in satin, which i could also rub out the gloss to a satin I see, but some say different. I also cant use steel wool on this product so rubbing it out prbably isnt an option
thanks cmascolo, the first 4 coats can be applied within 24 hours as long as dry to touch, and after 24 hours needs sanding. i will take the advice for further coats to wait 24 hours between each one. I have 3 done. Probably 10 or 2 more gloss and then 1 or 2 satin
After sanding blow the dust out with pressure air if available and the then vacuum. Tack cloth adds solvent material to the wood that might interfere with your finish
Shellac is one of the products that will blend the layers of finish together.
I have found that a Swiffer Dry Dust cloth does an amazing job removing dust providing you have properly sanded the board and layed down a couple of top coats. Wiping the bare wood hangs up the cloth leaving fiber behind. Blow of the dust for the first couple of coats.
Spraying the wood with compressed air followed by a clean rag or old t shirt is my standard approach. If that leaves too much dust behind, it doesn't hurt to dampen the rag and go over it again. Tack cloths can leave behind adhesives and solvents that may interfere with the finish. Polyurethane isn't usually a problem but you may run into issues using tack cloths on other finishes.