Varnish over oil varnish finish

[Rob Moore]

I am refinishing a very nice cherry desk that my brother gave to me a while back. It had what looked and felt like an oil finish but the top was looking a bit worn so I decided to sand it down and apply a few coats of Watco Danish oil to retain that in-the-wood feel. After thinking about it some more (and rereading posts here and Flexner's "Understanding Wood Finishing") I decided that since this desk will now go into my 10 yr old son's room it might benefit from a more protective finish. I have Waterlox orig sealer/finish and also a can of Waterlox orig satin finish. I've waited a week for the Watco to cure and have begun applying Waterlox. I gather from some posts here that Watco doesn't have all that much varnish in it, and I wasn't sure how best to apply the first coats of the Waterlox sealer/finish but ended up doing the "bus boy wipe the table approach" that folks here have advocated. I applied two coats over a few hours and now am wondering how best to apply the next coats, and also which of the Waterlox products to use. Some questions:

1) If my goal is to have a satin finish, should I just go right to the Waterlox satin finish or should I apply another coat or two (or more) of the sealer/finish, which I gather is a thinned version of the "full strength" Waterlox finish? The satin finish can says to use the sealer/finish first for a few coats, but maybe that's with bare wood and I already have the Watco there.
2) Can the Waterlox satin finish be wiped on or is it too thick without thinning?
3) At this point, how long do I need to wait between coats of finish and does it matter which product I use (sealer/finish vs satin finish)?
4) When is the best time to gently sand to get a nice smooth finish? In between coats of finish or when I'm done and the finish has cured after a week or (or both)? I don't need to rub out the finish since it will already be satin, I just want to make it smooth.

Thanks in advance.
-Rob

[Dan Hahr]

You ca build up the finish with the sealer and then end with a coat or two of satin. Sometimes it takes a few to get an even finish.

Dan

[Rob Moore]

Thanks Dan. I built up the finish by wiping on a number of coats of the Waterlox sealer/finish, then brushed on a coat of the satin Waterlox, thinned slightly (about 10%) with mineral spirits. Not sure whether it was my brushing technique or the fact that it was 90 degrees in my garage, but I see lots of small bubbles and brush marks (maybe add more mineral spirits next time?). I wet sanded the next day with 400 grit wet/dry paper, and the surface is now smooth.

My plan is to wipe on a final coat of thinned satin. Will those "flattened" bubbles and brush marks telegraph through after I wipe on that last coat?

[Kent A Bathurst]

You need to wait 24 hrs then scuff sand the brushed-on finish. I use 320 - 400, either 3M 216U [preferred] or Norton 3X sandpaper.

Now you can use a wipe-on coat of the W'lox. Thin the W'lox 50/50, then wipe it on with a Blue Scotts Paper Towel -- lint free, no embossing.

For future reference, you kinda did it all backwards, from my perspective. One coat wipe-on sealer, then brush to build film. One brush coat = 3 wipe on coats.

Wait 24 hr between brush coats, sand as above. Then, top it off as above with the wipe-on. The point, of course, is that the wipe on is thinned much more, and it allows the bubbles to exit, you get fewer bubbles to begin with via wiping, and it flashes off to tack much faster, giving dust critters a smaller attack window............

[Rob Moore]

For future reference, you kinda did it all backwards, from my perspective. One coat wipe-on sealer, then brush to build film. One brush coat = 3 wipe on coats.

Wait 24 hr between brush coats, sand as above. Then, top it off as above with the wipe-on. The point, of course, is that the wipe on is thinned much more, and it allows the bubbles to exit, you get fewer bubbles to begin with via wiping, and it flashes off to tack much faster, giving dust critters a smaller attack window............

Thanks Kent. I realize one can build up the finish faster by brushing but my good brush had dried varnish on it from another project and I hadn't yet read posts here about how to get it back into shape. It's been hot here so I've been able to use Scott Holmes' approach of wiping 3-4 coats of the Waterlox sealer/finish in a day, and do that for a few days.

I did wait a day after brushing the satin Waterlox, then wet sanded it flat, and today I ended up wiping on a coat of thinned satin finish, though probably could have thinned it more than I did. I still see a lot of lines from wiping. In Flexner's book, in the chapter on "Finishing the finish" he talks about rubbing it out to "hide" the bubbles and brush marks. I was wondering if I should call it quits now (I have enough finish on), wait 1-2 weeks for it to cure, and rub with 0000 steel wool (I want a fairly flat-satin finish), or apply another coat of thinned varnish and hope that I don't see as much of the wiping marks. I think the finish is drying so quickly because it is so hot. But if the rubbing out will make these disappear, I'm fine stopping now.

[Kent A Bathurst]

Thanks Kent. I realize one can build up the finish faster by brushing but my good brush had dried varnish on it from another project and I hadn't yet read posts here about how to get it back into shape. It's been hot here so I've been able to use Scott Holmes' approach of wiping 3-4 coats of the Waterlox sealer/finish in a day, and do that for a few days.

I did wait a day after brushing the satin Waterlox, then wet sanded it flat, and today I ended up wiping on a coat of thinned satin finish, though probably could have thinned it more than I did. I still see a lot of lines from wiping. In Flexner's book, in the chapter on "Finishing the finish" he talks about rubbing it out to "hide" the bubbles and brush marks. I was wondering if I should call it quits now (I have enough finish on), wait 1-2 weeks for it to cure, and rub with 0000 steel wool (I want a fairly flat-satin finish), or apply another coat of thinned varnish and hope that I don't see as much of the wiping marks. I think the finish is drying so quickly because it is so hot. But if the rubbing out will make these disappear, I'm fine stopping now.

OK - I gotcha. Yeah - that's the same - you threw me when you said "sealer/finish". I always think of it as just "wipe-on" version.

The 50/50 does matter -- if it is too thick, it won't "flow" to hide the wipe lines. And - if you read enough of Obi-wan Holmes' posts, you will find the bit about wiping "like a kid wipes a table at Denny's." If the desk top is, say, 24" x 60", it should take you all of 3 minutes to apply the wipe-on coat. Maybe 2 minutes.

YOu aren't trying to wipe like you brush. I've never had a problem seeing wiping marks...the hotter the weather, the more you need to thin it, so it will be down, and - briefly - have time to level itself, before it has cooked off. I don't think an additional thinner coat will hide the wiping marks from previous coats.

As far as final finishing with 0000 steel wool - - many materials can be used. Typically, the rules for rubbing out are to wait at least 4 weeks, which is how long it takes to reach a full cure.

Me? I would sand it until the wiping marks are gone, and then hit it with one coat of thinned varnish. You can always go the 000 route, and use this as a fallback if you don't like the results.

Oh - your brush with the dried varnish on it? Fire up the bugle, and play Taps for it, is my advice.

[Rob Moore]

I have read lots of posts on varnish techniques in the finishing forum and did in fact use the "kid wiping a table at Denny's" approach. And it worked well with the thinned sealer/finish wiping varnish but I suspect I didn't thin the full strength varnish enough when I wiped it. I think I'll sand gently and wipe on another coat, this time making sure I carefully measure how much I thin the full strength varnish, and shoot for 50:50. Then I'll wait several weeks and rub out.

For the final rubbing out, was wondering about using wax--is it typical to wax the top of a desk?

As to tossing my brush--I was actually able to restore it using Scott's advice of paint stripper--it came out pretty well. And this time I watched his excellent video and cleaned it properly after using it.

[Kent A Bathurst]

I have read lots of posts on varnish techniques in the finishing forum and did in fact use the "kid wiping a table at Denny's" approach. And it worked well with the thinned sealer/finish wiping varnish but I suspect I didn't thin the full strength varnish enough when I wiped it. I think I'll sand gently and wipe on another coat, this time making sure I carefully measure how much I thin the full strength varnish, and shoot for 50:50. Then I'll wait several weeks and rub out.

For the final rubbing out, was wondering about using wax--is it typical to wax the top of a desk?

As to tossing my brush--I was actually able to restore it using Scott's advice of paint stripper--it came out pretty well. And this time I watched his excellent video and cleaned it properly after using it.

YOu don't need a beaker graduated in ml for the 50/50 - just be in the area. If it is shot, maybe even over-thin it a bit from there....you can always put down a 2d coat after an hour w/o sanding..........

Good news on the brush.........lesson learned, eh?

Remember - you can rinse the brush in ms, then suspend it in ms - don't let the bristle touch the bottom of the cup/jar. It will keep just fine for up to a week. YOu don't need to wash it after every lap in the finishing process.......save time and ms.

Wax is up to you. Doesn't add any protection to speak of, but makes it "glow", and feels very smooth and slippery........... IF you do, get the Antiquax, is my advice.