advice on how to eliminated raised grain on basswood.

[Wolf]

I carve characters in southern basswood. If the carving is done with knife and chisels then finished with acrylics, stain, and then polyurethane it looks great. Often a carving requires sanding, usually done in a sequence running from 150 to 400 grit, but when painted the moisture raises the grain to the detriment of the carving. I’ve tried successive sandings after sprays with water and alcohol which helps, but does not produce an acceptable quality finish.


My wife, who does the painting, is committed to using acrylics. So id really appreciate any suggestions on eliminating raised grain problems.

Wolf,

[Tom Ellis]

Wolf, I seal a lot of my caricatures with Watco Danish oil finish before painting, and find that helps a lot with the painting. The carving even looks better after just putting on the oil.
Tom

[Wolf]

Thanks,

I've never thought of using oil on a carving after sanding, but since I've some Danish oil in the shop I'll give it a try in the morning.

[Donald K. Mertz]

Consider this about sanding: it is commonly thought that sanding smooths out the wood surface while in fact it roughs it up all the more. Sanding paper is a "cutting" tool. Let's say 150 is 150 cutting teeth scratching the wood surface. 400 grit is 400 cutting teeth scratching the surface. Even though water and/or alcohol is used to raise the scratched grain, yet more sanding continues to scratch the surface. One has to sand a long time with very fine abrasive to produce the finest of scratches to make it feel and appear to be smooth. On the other hand, slicing with the cutting teeth on the cutting edge of a knife or chisel will separate the fibers and the side of the knife or the bevel of the chisel will burnish (polish) behind the cutting action of the teeth on the cutting edge leaving a slick surface. Rubbing the surface of the wood with a crumpled up brown paper bag "burnishes" the surface (wood fibers in paper bag rubbing against carved wood surface) brown paper bag does not sand, it burnishes. An oil medium creates a softer finish melting the wood fibers to each other and filling in the micro-scoptic gaps or scratches in the wood. I prefer to us only oil, but some painters use oil first with acrylic on top of the oil with reasonable success. I never sand my carved pieces as I prefer to have the slicing cut of the tool and the burnishing of the tool to create a slick surface and besides, sanding is a lot of work and I am lazy. Stay Sharp and Be Carveful, Don

[TreeWizard]

As well as oil you could try a sanding sealer. I've tried both Boiled Linseed oil and sanding sealer and find both work well.

[Tom Ellis]

I'm with Don on this one Wolf. If you use a good sharp knife, there should be no need for sanding, and personally I like to see the knife marks on the carving when I am done. I still use the oil though.
Tom

[Irish]

A good knife does reduce the amount of small fuzz bunnies and rough areas in a carving but often I find that basswood in particular does need just a little more help with sanding.

If you are sanding up to 320 grit your eye really can not see all those little scratches that Donald refered to but it can see that the surface appears much smoother.

I think what you running into is not from the sanding as much as from the water based acrylics hitting the raw, unsealed wood. Where you have cut against the grain, opening the grain ends, the moisture from the paint lifts and separates the individual grain lines in that area. So the end grain 'rises' above the rest of the carving.

Sanding sealer is an excellent suggestion as it does 'seal' those end grain areas. Oil as Danish or BLO also fills and seals the grain ends.

But before I use sanding seal or oil and after I have sanded I scrub the whositis out the carving with a 6" - 8" crunched up brown paper bag. The bag has enough grit to act as a sand paper removing those last little fibers.

When you are done with the brown paper bag sanding you can see that the surface of the wood has become shiny ... it's a very soft sheen but it looks almost as if you had applied a thin coat of oil. The paper sanding actually seals the wood by burnishing it. The pressure that you use to scrub with is enough to force many of the grain ends closed. Once closed they don't (can't?) react to the water in the paint.

Your wife might want to also try using a gesso coat before painting. Mix white, black and a touch of burnt umber acrylic paint to create a pale coffee grey tone. Thin this with water about 2 parts color to 1 part water or even half and half. Then paint on two coats letting each dry throughly. Then do one more light sanding.

This very thin mix will let the grain soak up both water and color deep into the grain ends. The coffee grey color is used so that your more pure colors as cadmium red and ultramarine blue do not look streaky when applied.

Susan

[Wolf]

I want to thank you all for your responses to my question about raised grain. Sanding or burnishing with a paper bag works really well, even after the polyurethane has been applied to the carving. Interestingly enough, the paper bag also works to help finish turnings on the lathe. As for oil, I use it on relief carvings and on larger carvings of the type my daughters call “Artsy” and still have to try oil and acrylics on one of the character carvings. Also, using Gesso and sanding sealer works, but my wife, an excellent painter, paints by controlling the intensity of the wash partly by it’s absorption in the wood – So now we have some ideas to work on and develop with our style.

Thanks