1

I'm finishing a small side table using this water-based wipe-on poly, and wasn't sure how to go about "rubbing out" the end product. I was planning on following this video. Basically, sand with a fine grit sandpaper, go over it with #0000 steel wool, and then go over it again with the steel wool, but with soapy water as a lubricant.

Since the finish I'm using is water based, is using steel wool in this process okay? I know that steel wool isn't supposed to be used before the finish or in between coats, but I wasn't sure about using it after the finish is applied. If it's not ok, what are some alternatives? I've seen synthetic steel wool, but the ones available at the local big box stores seem to be of not very good quality.

  • I was about to say there is no waterbased wipe-on poly, but they went ahead and made one! If you're planning on rubbing out at the end though I don't know why you don't just use the normal stuff because it'll build faster. Wipe-on varnish is intended to help minimise or prevent having to do post-finish work. – Graphus supports Monica Jun 24 '18 at 13:22
1

Since the finish I'm using is water based, is using steel wool in this process okay?

It's not ideal but you can use it if needed.

But I would recommend not using it lubricated with soapy water as the potential for rusting is very high — I've put pads down I was using to clean glass and just a few minutes later have come back to them to find the pad sitting in a small puddle of rusty water.

If it's not ok, what are some alternatives?

An incomplete list includes:

  • finer abrasive papers/films or sponge-backed abrasives
  • bronze wool
  • stainless steel wool
  • powdered pumice and/or rottenstone powder
  • non-woven nylon abrasives AKA synthetic steel wool
  • automotive scratch removers, rubbing compounds and polishes

This shouldn't be read as a list of alternatives only as various combinations can be used in sequence, e.g. abrasive papers up to a high grit number, then rottenstone lubricated with a light oil, finally using a fine automotive polish or swirl remover.

I've seen synthetic steel wool, but the ones available at the local big box stores seem to be of not very good quality.

It is wise to avoid this if the quality is suspect, because the abrasive grains tend not to be graded well in cheap stuff. This can lead to scratches just like you get if an abrasive paper is contaminated by a speck of grit from a coarser grade.

Note: do be sure to wait sufficient time before starting to ensure best results. While the short drying time of waterbased finishes seems to indicate a very fast cure time it's still generally necessary to wait at least 48 hours, sometimes as much as a week, for the finish to harden completely.

0

Once the finish has cured it cannot be "reactivated" by water. You can safely wet sand your work after a few hours. (I'd probably wait overnight, though. Any tackiness or "rolls" when sanding mean it's not fully cured).

Finishes like poly do not just "dry", they also "cure" after the solvent has evaporated. That means that there is a reaction in the film that bonds it into a solid layer that cannot be removed with more of the same solvent.

The only exception to this is shellac (and some lacquers). It can be reactivated even years later with more alcohol. This is why the layers "burn in" to each other, preventing witness marks that you'll if you happen to sand through the top layer of poly.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.