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Discussion Starter #1
I've done several weeks worth of reading and I can't seem to find an answer to this question. I am refinishing the chestnut molding in my house. I stripped all the shellac, sanded to 180, and then applied my oil based stain. I am padding on a 2 lb cut of shellac for my finish of choice and I have found that scuff sanding between coats does nothing to the finish.

My question is, when do I stop applying the shellac? I'm not sure that I will stay with the gloss finish and may flatten it a bit after it hardens. Chestnut has very deep grain. Do I keep applying the shellac until the grain is filled and the shellac feels even? Visibly it looks even, but you can always see the and feel the ridges in the wood.
 

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There are two reasons to sand between coats. The first is to remove any dust nibs or other goobers that end up in the coating. The second is to provide adherence tooth for the next coat. This is important with some finishes that don't melt into the previous coat. Shellac does melt in, so you don't need to sand unless removing junk in the finish.

It takes many many coats to fill grain. Typically this is done with a grain filler before the top coats. It's not practical to try to fill with shellac. Since previous coats are activated by the alcohol, you can make a mess applying too much. Don't worry about the grain being filled, it's not necessary on trim work. Embrace the characteristics of chestnut, it's supposed to be a bit rustic.
 

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Discussion Starter #3
Thanks for the reply. If I decide to remove some of the gloss and go to a satin appearance, can I do it without wax? If I use wax, how often do I need to re-wax?
 

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You don't want or need to wax the trim in your house. I can't recall ever hearing anyone actually waxing the trim......As was stated, if you want a smooth finish then you need to fill the grain first. Finely ground pumice and linseed oil is a great old school way to fill the grain. You can also use shellac and pumice for that matter.
 

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A few things, I would have sanded it up to at least 320 before finishing. Laying finish out over wood that has only been sanded with 180 is why its so rough and your having problems sealing the grain, although I totally agree with the other guy, grain filling house trim seems like a waste of time. At this point with the shellac being a higher sheen than you want I would just scuff it and finish over it with a satin water base. Waxing is still going to leave the sheen higher than you want most likely and it's more work than is necessary.
 

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Flattening Shellac

When I do shellac I find that a sanding between every 2-3 coats helps promote a flat finish. Generally, when applying additional coats does not add any depth or gloss to the existing coats you have added enough coats.

As others have mentioned fillig the grain with shellac takes many coats (10-20!) which leads to other problems. If you think about it, using shellac to fill grain means that you have to sand down all of the area (except the gain) to be even with the filled depressions (grain).

In terms of order, sand, stain, shellac, sand, shellac, sand,..... finish

Unaltered shellac is a bit glossy for my tastes so I have tried a few approaches to flatten it out

1) 0000 steel wool. In my opinion it looks like a bunch of fine scratches and cloudy
2) Waxed - looks good but shows fingerprints and needs periodic rewaxing
3) Rubbed out - My favorite so far - gives a nice flat clear finish. I wet sanded (with mineral spirits) with 320 then 600 then applied paste automotive scratch remover (no kidding) and buffed with a towel. Folks that really know what they're doing use pumice and other professional techniques/materials.
4) Shellac Flat - never tried this but there is a product under this name that supposedly flattens the finish when added to a batch of Shellac.

Sand your shellac with 320 or at least 220. The other downside is that once you have many coats and apply more coats it takes a LONG TIME for the sum total of the coats to dry to a point where it can be dry sended without clogging the sandpaper. When sanding make sure not to sand through the shellac - I usually wait until I have 3-4 coats before sanding.

I found that using a good silicon carbide sandpaper helps for dry sanding but even cheap sandpaper will work when wet sanding.

One more tip - I recommend using a maximum of a 2lb cut shellac. The hardware store stuff comes out of the can as a 3lb cut which is pretty thick and harder to apply with a brush. While working with a more diluted cut (1 1/2 is my favorite) it is easier to control but takes more time to apply due to more coats. If you're using a higher cut dilute with denatured alcohol - you can find charts using google.

brian
 
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