Sanding Sealer & BLO Questions

[Vaughn McMillan]

I'm a rank amateur in most things, especially wood finishing. I'm working on a trinket box, with sides and top of padauk. I've sanded to 220 grit, and tonight I put a coat of BLO on it. After closer examination, I see quite a few open pores in the padauk that I'd like to fill, so I can get a smooth, glossy finish. I know very little about sanding sealers, but from what I've read here it seems that might be what I'm looking for to fill the pores. So...the questions:

Will a sanding sealer fill the pores?
Can I apply a sealer over BLO?
Did I shoot myself in the foot by applying a coat of BLO already? (In other words, did I already BLO it?)

If the answers to the above questions are NO, NO and YES, what would you Creekers suggest to get a smooth glossy finish? (The box is natural-color padauk and maple.)

Any suggestions are welcome -

- Vaughn

[Jim Becker]

Unless you are using lacquer, "sanding sealers" are just another way to get money out of you and will, in fact, weaken your finish. The searates in them (that make sanding easy and also act as a filler) are very soft, which means you end up with a soft finish under your "hard" top coat. (Lacquer sanding sealers are different as they become "one" with the top coats and don't have the negative properties of "regular" sanding sealers)

You have several options for filling the grain. You could apply more BLO and wet-sand it to create a slurry that will fill the grain as long as it's not "really deep". You could seal with a coat of super-blond shellac or a water-bourne finish and then use a paste grain filler, such as Behlen's--good for open grain woods such as oak, ash and mahogany. (Never put it on bare wood!) You could just build your finish and sand it back carefully until you have both filled pores and a very smooth surface. The super blond shellac could be great for that as it builds nicely and when padded, will gleam. It's a wonderful finish for so many things.

[Vaughn McMillan]

Thanks for the info, Jim. Your answers begat more questions. When you refer to wet-sanding, is the "wet" from BLO or from water after the BLO has cured? What grit of wet-or-dry sandpaper do you recommend? The shellac route is also interesting. I know it's typically mixed from flakes (with denatured alcohol, IIRC) but are the pre-mixed products worthwhile? Also, you refer to shellac having been "padded". I'm not familiar with that term in this context. Lastly, are any of the finishing products (particulary shellacs and lacquers) at the borgs (HD and Lowes) worth buying? Or should I wait until I can make a trip to someplace like Rockler?

Thanks again Jim -

- Vaughn

[Don Baer]

Vaughn,
I'm not Jim but when I wet sand with the BLO I just put on a liberal amount of BLO on the piece and use something like 220 grit paper while its wet then sand away. Let the BLO and sand dust fill in the wood.

I'll wait for Jim to answer about the shellac.

[Martin Lutz]

I have used BLO and Pumice to create a slurry and wet sand the slurry with a soft cloth. the pumice fills the small holes, polishes , and seems to work very well. I have only used it once so I am by no means an expert but it worked. I would try it on scrap first.

[Don Baer]

Vaughn,
Here is a post where I asked a similar question.

http://www.sawmillcreek.org/showthread.php?t=21052

[Steve Schoene]

Zinner, who makes almost all of the mixed shellac products sold in the US does make a product called Seal Coat that is dewaxed shellac. Haven't seen it at the Borgs, but do see it at some good paint stores. That works fine, and can be overcoated by any finishing material including waterborne. For a trinket box shellac would make a good top coat just by itself, and wouldn't need a separate topcoat. Padding on shellac just means using a cloth "pad" to apply the shellac. You can make several passes applying thin coats of shellac, let it dry for a few hours, and sand it lightly. Then apply a couple of more coats. Wait a little longer, sand lightly again and put on anouther couple of coats. It won't take too long on padauk for you to see the surface fill. Then,you can rub down the shellac to whatever sheen you desire.

The secret to padding on shellac is to move quickly and apply light coats--not flooding it just wetting. Don't go back--any skip will be taken care of on the next pass. And if the pad starts to seem "sticky" --STOP. It is beginning to lift lower coats.

[Don Baer]

Lowes carries Zinseer Shellac.

[Jim Becker]

Lowes carries Zinseer Shellac.

So does the 'Depot. I've used it when I ran out of flakes. It's fairly light in color and as Steve mentions, it's a de-waxed product that can be used under polyurethanes as well as water bourne products. (alkyd and phenolic varnishes can also go over "regular", wax bearing shellac)

And as Don and Martin mentioned, just use the BLO and paper (I use 220 wet and dry) to do the slurry...pumice is optional, but can be a big time-saver with very open pores. The really nice thing about this grain filling method is that you are using the wood, itself, to do the job...a nice natural look.

[Vaughn McMillan]

Thanks everyone for all the info and recommendations. I stopped by Lowes on the way home and grabbed a can of Zinsser Amber Shellac and some denatured alcohol (since the shellac can recommended cutting the 3# mix down to 2# before using as a wipe-on finish). I decided on amber because I'd like see the maple parts of this box be a little darker, and I figured it couldn't hurt the way the padauk looks either.

Since this box is a combination learning experience/experiment, I'm torn between wet sanding with BLO just to see what it looks like, or building up enough shellac to fill the pores. Seems the shellac route might be quicker since it dries faster, but I'm probably going to end up doing some of both, just to learn.

Thanks again, all -

- Vaughn

[Jim Becker]

Just remember that the Zinsser Amber Shellac is NOT de-waxed, so if you decide to top-coat, it should not be with any form of polyurethane varnish or a water-bourne product. That said, it's a nice product and getting some practice with it is a good idea. Use a good brush (dedicated to shellac is best) to apply or use a soft lint-free toweling to wipe it on. Shellac is not like varnish...it does not build in layers. Multiple coats "become one" as the alcohol flashes off. Steve Mickley has some useful comments on shellac at this link: http://johnjacobmickley.net/Shop%20P...ng%20Frame.htm

[Alan Turner]

Vaughn,
Another way to do it is the rather traditional french polish method. That is, put on a liberal amount of BLO, and then sprinkle some pumice or rottenstone on the surface, and wipe it off cross grain, which will fill the small pores of the padauk. Let it dry at least a day or better yet 2 days. Then top coat with shellac. One coat, padded, medium heavy, dry, then sand back the nibs. At this time the surface should have no pores. Then, use a rubber for the shellac, and simply french polish it, using mineral oil as a lubricant, keeping the pad moving at all times. This way you can build up a heavier coat pretty quickly, which will give you the dopth of sheen I think you are looking for.

[Steve Schoene]

Just a note about shellac brushes. Good varnish brushes--badger, well flagged china bristle, are not good shellac brushes, the bristles are too large and the brushes have "reservoirs" that put on too much shellac at the beginning of a stroke. The best I've found have Taklon Gold "bristles". The fiber is very much like good sable--as if one could afford that--and leaves a smooth finish that doesn't need to flow out like varnish. A 1 1/2" is about as large as you want to go. The best have been Windsor Newton but other similar brushes are around that are probably nearly as good but for less money. What you are looking for is a flat water color (colour) wash brush. You are more likely to find a good one at an art supply store than a paint store.

[Vaughn McMillan]

The SMC gang's collective knowledge continues to amaze me. Thanks for the additional suggestions. The link to Steve Mickley's site was a good read, Jim. It also saved me from asking Alan to define "rubber". It's also good to know shellac is partial to certain brushes. I would have just grabbed one of my bulk throw-away brushes without Steve's input.

Tonight I did a wet-sanded coat of BLO on the box. I started with 400 grit, saw I wasn't making any appreciable slurry, then switched to 220 grit. After slathering padauk red linseed oil juice around for a few minutes, I let it sit for 15 minutes or so then wiped it down lightly with a cotton t-shirt rag. It doesn't seem to have made much headway with the pores, but I'll see how it looks after sitting overnight. Should I expect to need more wet-sanded coats of BLO before I see the pores full? I didn't want to leave the slurry on too thick for too long, since I've learned the hard way what happens when you leave BLO on too thick overnight.

I'm planning to use the shellac as the final finish (no top coat other than the shellac, so the fact that it's not de-waxed shouldn't be an issue). I'm looking forward to playing with it and getting a feel for how it's applied. Now of course, I should be practicing on pieces of scrap, but since the box itself is made of leftover shorts, I guess I am practicing on scraps. It's just that the scraps are cut and glued into a box-shaped form.

Thanks again -

- Vaughn

[John Gregory]

You could seal with a coat of super-blond shellac or a water-bourne finish and then use a paste grain filler, such as Behlen's--good for open grain woods such as oak, ash and mahogany. (Never put it on bare wood!)

Jim,
what would you put on the wood prior to the Behlen's on red oak? The reason I ask is that we use a lot of red oak and I am disappointed when some of the deep grain takes the stain so dark. I am hoping the use of Behlen's will help me even out the color on red oak projects as well as fill the pores. I was thinking of applying Behlen's prior to staining.

Thanks
John