0

I want to bring out the grain of a wooden board as a relief with two-tone paint job, in the manner of the test piece below. (I'd roll the top color onto the real piece rather than brush it.) The board is about 45x35 cm, well-dried softwood from some furniture.

This was done with a rotating steel brush which worked ok, with patience, except that it leaves brush grooves. Sanding those down manually is pretty tiring for the fingers and only practical down to a certain width of grain stripe.

I could sand out the soft stripes with a multitool instead, but without a flex shaft the tool is a bit fat, using the sandpaper rolls inefficiently and destroying them too quickly by uneven wear.

Are there other ways to differentially and evenly remove the grain's two densities wood, perhaps even non-mechanically? Or hints on smoothing the valleys after wirebrushing?

6
  • Hi, welcome to Woodworking. How much of this do you need to do? There are established ways of preferentially removing the softer earlywood from softwoods like pine or fir, and one of them is what you've already tried, slow as it is — this is generally not a fast process, and a realistic expectation should be that it will take hours plural. The amount of work needed to smooth the surface down afterwards is very variable, since everyone's standards are different. But if done by sanding, for anything other than a smallish area it's definitely not something you'd want to do manually!
    – Graphus
    Sep 12, 2023 at 13:48
  • Now colouring the wood the way you want to is not straightforward and will present its own set of difficulties; it's actually rather difficult to do when you need two colours. But you can cross that bridge separately after you've investigated whether the surface prep is within reach.
    – Graphus
    Sep 12, 2023 at 13:51
  • Thanks @Graphus. The board is about 45x35 cm, well-dried softwood from some furniture. The coloring needn't be perfect; what hurdles do you foresee beside some smudging and running?
    – ariola
    Sep 12, 2023 at 16:32
  • @Graphus Exactly, I'm asking after nonmanually, if available!
    – ariola
    Sep 12, 2023 at 16:34
  • Would surface-preparation be an appropriate tag?
    – ariola
    Sep 12, 2023 at 16:35

2 Answers 2

1

Are there other ways to differentially and evenly remove the grain's two densities wood, perhaps even non-mechanically?

One thing about sanding softwoods is that you actually have to take care not to accidentally create an uneven texture (sometimes referred to as a 'corduroy surface') because of how much softer the pale earlywood is compared to the dark latewood. This is why sanding with unbacked paper (just the fingers behind the paper, especially a single layer of paper) is not the way to do it. But this results in a texture that's much more subtle than I think you want/need.

For a pronounced texture, one of the classic ways to do this on a larger scale is by sandblasting. I wanted to recommend this, but it is unfortunately probably out of reach as a technique for you since even at the rudimentary level (where you'd make your own blasting gun following online guides) it requires a decent compressor, likely out of budget for a single project.

It is also done by wire brushing but in a way that isn't replicable at home — IIRC they use belt-fed machines with wide wire brushes, and the wire seems like it's much finer than that in a typical wire wheel available to chuck up in a drill.

For one more potential method, see bottom.

Or hints on smoothing the valleys after wirebrushing?

The valleys are obviously the difficult part, since it's so hard to get anything in there to smooth out the wire-brushed texture. Although sanding without a block naturally does do this to an extent I think it's likely that no amount of conventional sanding is going to do it, given how much lower the earlywood will be once it's already been worn away by wire-brushing.

Perhaps the only way to do this is efficiently is by using one type of abrasive nylon brush, various types shown below:

Nylon abrasive wheels

Given these are available in a range of grits, it opens up the possibility of doing the entire process using two or more such wheels.

1
  • Cool, I'll try the nylon brush.
    – ariola
    Sep 14, 2023 at 8:12
0

Are there other ways to differentially and evenly remove the grain's two densities wood,

Sandblasting is a common method.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.