Low-sheen finishes

Are streaks and scratches impossible to avoid with hand-rubbed finishes? June 24, 2001

In an email group, some professional refinishers were discussing using the 9 pound (#4000) and 30 pound (#600) Stuhr dual pad pnuematic rubbing machines to achieve low sheen rubs with no streaks. While they shared many tips, no one had a great solution. I emailed a bigwig at one of the major furniture factories. His solution was to do off-the-gun finishes in dust-free drying environments (try that onsite or in your garage in the summer!).

Are streaks a necessary evil when we do hand-rubbed finishes? Will the scratch patterns always appear to haze a surface in the wrong lighting situations?

Forum Responses
It's sad to say, but off the gun in a dust-free environment seems like the only way to get flat or semi-flat sheens that don't suck. Theoretically, something that was quasi-non-directional might work. Straight-line sanders like the Stuhr, it would seem, can't possibly work, as you're always going to see the scratch pattern. A specific grit of Mirka Abralon on a random orbit sander, followed by paste wax to fill the scratch pattern, might get close. I live in the desert and if it's a calm day, I can shoot a fast-dry pre-cat and within a minute it's dust free dried. My SATAJet NR95s spray well enough that the finish goes down perfectly (except if I have the misfortune of running into the occasional suicidal bug). Normally, my climate lets me slide by. Most people don't have this situation going for them.

The look that is needed can't be achieved from a low sheen topcoat. Depending on what you do, it's all in the grit sequence and the machine you're using. The 30# Stuhr rub machine gives you the nice flat cut look. After that, it's done by hand-rubbing the finish.

I also did most of the sheens off the gun. But when I needed to rub, I used a short nap, high quality wool carpet on my machine. Hardly ever got streaks. Also used a little flax soap or woolwax in the water.

Bob Niemeyer, forum technical advisor

My problem with a rub-out finish, unless you rub it out to a high gloss with a few glazing compounds, is that you are effecting the long-term durability in the process. Most finishes have a wax surfactant that acts as a protection against abrasion. The abrasion process of rub-out will remove this and give your customer a less durable finish than the one you applied. In my pre-spray booth years, I did some very acceptable flats and satins off the gun. Now, in California, we have a very long spray season with respect to temperature, humidity and bugs. You may try increasing your thinner mix to accelerate dry time, in the range of 70% to 50%. Wet your garage floor down, redirect your fan, buy a new downdraft booth and UV dry booth. The physics involved in abrading a surface versus a finish with a microscopic flating agent is against you.

Please give details on what you do with the carpet. You attach it to the pads and load it up with rubbing compound?

Check out this thread: Buffing out a lacquer finish

A friend of mine asked me to try rubbing a coating with a gray scotchbrite wrapped around a thirty pound brick and to see if I don't get a streaky sheen. His point was that the Stuhr 1000s and 4000s with steel wool are part of the secret to a satin or dull rubbed streak-free finish.

I'm still hand-rubbing the old fashioned way, by hand.