Replies

1. 
   Rich14 | Apr 04, 2005 03:51am | #1

   Eric,

   It's hard to keep a wet edge with shellac by brushing and that's your problem. The alcohol is evaporating too quickly. Is your shop too warm?

   There are several solutions. The first is simply your technique. Brush in one direction only with a full brush. Don't mess around trying to go over the first lap. Then brush the next course immediately, overapping the drying coat with the new by an inch. You have to work rapidly, but not in a hurry. That advice sounds contradictory, but it's not. Practice a lot on scraps prepared (sanded, stained, etc,) just like the final will be. After a while, you'll find that the lap marks don't happen any more.

   Second. Apply shellac by spraying. I always spray. Once you learn how to spray, you will not want to brush at all. If you don't have spray equipment, shellac comes pre-mixed in spray cans. It's really expensive to use if you have a lot to do. But if the job is small, the convenience factor really makes the extra cost insignificant.

   Third, retard the evaporation of the alcohol. A little turpentine can act as a retarder. Isopropyl alcohol evaporates slower than ethyl or methyl alcohol. You can add some isopropyl alcohol to your shellac mix. You'll have to experiment a little, but the various alcohol ratios in shellac solvents are not at all critical. Just make sure you don't introduce any water into the mix.

   Off the shelf lacquer thinners can also work as retarders, but this is iffy. Lacquer preparations contain "solvents" and "vehicles" that are designed to evaporate at different rates. The slowest alcohols in the mix make sure that the lacquer stays fluid long enough to self-level. Thinners meant for brushing lacquers have the slowest-evaporating solvents.

   Rich

   Don't ever learn anything new. Rather than give you satisfaction that you know more than you did, it will only confirm you know less than you thought by opening horizons to things of which you had never dreamt and which you now must explore.

2. 
   AlbionWood | Apr 04, 2005 05:38am | #2

   Yes, I do have that problem. I've just worked on improving my brush technique, trying to work small enough areas to keep a wet edge, and trying to make the edges of successive strokes match up exactly. It's not easy.

   The other way to combat this is, only brush on the first coat; sand it level; then pad on successive coats. I find it eeasier to avoid lap marks when padding, probably because the coats are so thin.

   I just got a cheapo HVLP spray rig, but have to move my compressor before I can try it. Hoping that works!

   "Everything should be made as simple as possible, but no simpler."  A. Einstein

   http://www.albionworks.net

3. 
   BG | Apr 04, 2005 03:33pm | #3

   Eric,
   Within reason, I just find it's easier to fix shellac drips, etc. than worrying about the application process too much. After I've applied the shellac (or anywhere along the process) and rubbed out a bit, I make a rubber with the inards damp with alcohol...I dip the rubber in shellac and just lightly rub out any drip marks...takes very little time and all brush marks and drips are gone.

    

1. 
   Cirept | Apr 04, 2005 04:38pm | #4

   Thanks everyone, good suggestions.  I've done the padding method and with blonde -since it is transparent you can't see the areas of overlap, but with the dark I seem to get areas of streaking with the build up of the dark shellac.  Usually like two or three coats to get the right tone, and the more coats I apply the greater chance of having a build up of more shellac which show up as dark lines, frustrating, but I guess I'll have to wlook closer at my technique.