Clear Grain Filler for a Writing Desktop
Finishers discuss the attributes of a good clear grain filler. February 13, 2006
Question
I am looking for a good clear grain filler for woods like oak, ash, and jatoba that would be appropriate for wood surfaces that will occasionally be used for writing. It must be lacquer, CV, or postcat poly compatible. Does anyone have any suggestions?
Forum Responses
(Finishing Forum)
From contributor A:
How about lacquer filling the grain?
From contributor B:
Don’t bother filling oak. One sealer coat and a final coat about 4 mills is good. Oak looks like a paper or laminate completely filled and the dark grain gets milky with fillers. Ash is the same way but looks best with two sealer coats well sanded, depending on the sheen you are trying to achieve. Again, Ash looks fake when completely filled. Denser woods look like plastic when completely filled. However, if you are using a solid pigment that works well on ash, Sherwin Williams has a good grain filler for that.
From contributor C:
The best user-friendly product is a material by ML Campbell called AC Sealer. It is a post catalyzed product that reduces with lacquer thinner. It has an 8 hour pot life. It suffers from minimal shrink back, meaning that in maybe two months time what was a 100% grain-filled and smooth surface may start showing a little bit of texture. Two coats are all it takes in many cases. You lay it down, wait 20 or 30 minutes, sand way back to almost the flat of the wood and apply again, and sand way back again. It is meant to be a filler, not a coating contributing to your film thickness build. That's why you sand it way back.
If you need full filling and no shrink back then you should go with one of the polyester fillers offered by Ilva Polimeri (camger.com), ICA (icaamerica.com) or Chemcraft (chemcraft.com). Your pot life is real short but you are laying down a product that is nearly 100% solids by volume and weight. Lay it on, build it thick and grind it smooth, ready to receive your topcoats.
No matter what coating you use, if the surface will be used for writing then expect severe wear and tear. If you can get a real famous person to do all that writing on that surface then maybe 125 years or more from now the surface will be a real collectable gem and all that wear and tear will be part of history. No coating is bulletproof. No wood is bulletproof. High pressure laminate like formica is what you want if printing issues are going to haunt you or your customer.
From the original questioner:
We've tried lacquer, particularly the sanding sealer (CAB and precats) and none of them perform reasonably. They shrink up quickly and produce washboard writing surfaces again. We don't make it a habit of using such woods for surfaces but sometimes you get the customer wanting an island or something that matches their oak cabinets. And for sure, wood will get beat up. We make sure that all customers know that wood looks fantastic, but granite it isn't. I'll be contacting the local Campbell place for the AC sealer.
From contributor D:
Hood Finishing Products in New Jersey has a fast dry lacquer based clear grain filler that works great. You just need to take your time and not rush it, allow shrink back times and allow a bit more dry time than instructions state. Apply it in thin coats for optimum clarity but be careful as the product can get cloudy. I like to topcoat with Sherwin Williams CAB acrylic dull rubbed effect with some OK412 flatting agent added to adjust sheen. DRE is a good sheen and is pretty durable with 4-5 finish coats allowing adequate dry times and sanding between applications.
