Ask the Experts: Issue 9Comments (0)
This article is from Issue 9 of Woodcraft Magazine.
Getting Rid of Dust Nibs
Q: No matter how hard I try, I can’t get the air clean enough to totally avoid dust nibs in my finish when it dries. Do you know of an easy method to remove these nibs short of sanding them off with sandpaper, and then having to go through all the work of rubbing the surface with various grits of abrasive compound to achieve an even sheen?
Bob Flexner responds:
It may surprise you to learn that a brown paper bag (the type found at a supermarket) can do wonders for solving your problem. Simply tear off a part of the bag, or fold it to create a flat surface, and rub the paper over the dry and hardened finish. As long as the nibs aren’t really large, the paper will effectively cut them off so they can no longer be felt.
Not feeling the nibs is the key. When clients, friends or relatives admire your work, they almost always touch it. If it feels smooth, they are pleased. (They may even tell you how much they love the feel of wood!) They almost never inspect the surface in a reflected light trying to find the tiny dust-nib flaws, which may still be visible.
The “brown paper bag” trick works well on any finish, but obviously the finish must be allowed to harden well or you may create visible scratches. If you’re not sure a finish is hard enough yet, rub a non-critical surface such as a leg before rubbing the top of a table. Alternatively, apply the finish to scrap wood simultaneously with your project and rub first on the scrap.
Unfortunately, this trick is good only for tiny dust nibs. It won’t remove brush marks, orange peel or runs.
— Bob Flexner is the author of “Understanding Wood Finishing,” now in its second, fully revised edition.
Avoiding Chisel Damage During Sharpening
Q: Every time I sharpen my chisels, they go blue along the cutting edge. I know this isn’t good. What’s happening, and how much of a problem is it?
John English responds:
Some woodworkers still grind a primary bevel on a chisel using a standard metalworker’s bench grinder. That’s a problem because the machine rotates the grinding wheel so darn fast. When high velocity is combined with the coarse-grit wheels that come with most grinders, a whole lot of heat is created.
Back at the factory where your chisels were made, engineers hardened or “tempered” the steel they used by subjecting it to extreme temperatures. This allowed them to control the balance between hardness and brittleness.
When your chisel tips turn blue, you are heating up the edge along the bevel to a point where you are actually drawing out the temper, or hardness, of the steel. This leaves it too soft to keep an edge, and that’s a problem. If you want to stay with your bench grinder, you’ll have to invest in a much finer wheel, hold the tool against the abrasives for only a second or two at a time, and keep dipping the tip into a basin of water to keep it cool. A far better solution is to go with a slow, wet grinder designed to sharpen chisels, plane blades, etc.
Those chisels you’ve been sharpening will have to have all of the blued steel and perhaps another 1/8" or so beyond that removed, before you get to steel that will take and hold an edge properly. Depending on how aggressive you’ve been, you may even have to go further. In a few cases, especially when the steel is quite thin, the entire chisel may be ruined. The only way to know is to sharpen it properly and see how it holds up in use.
— John English is a contributing editor to Woodcraft Magazine.
Sealing Hand-Woven Seats
Q: I am replacing the fabric caning on two oak chairs. How do I seal or finish the fabric after it is in place?
Kerry Pierce responds:
I seat my chairs with two different kinds of material: Shaker tape (the fabric I think you’re talking about) and rattan splint. Each material requires some consideration in order to preserve an appealing look for as long as possible.
In the case of rattan splint, the process is pretty simple. I just apply to the woven seat whatever finish I’ve put on the chair’s wood frame, in most cases Waterlox. This tung oil dries to a durable finish and is easily washed with a detergent/water mix. Tung oil also helps the splint retain flexibility, an important consideration when you’re working with a seating material that can become brittle if untreated.
Preserving Shaker tape is more problematic. I Scotchgard Shaker-tape seats after they’re woven, and I do think that offers some useful protection from the kinds of spills dining chairs are apt to experience. However, nothing I know offers any permanent protection from the worst enemy of Shaker tape: fading.
Many years ago, I sold a pair of rockers with Shaker tape seats and backs to a local furniture store. The owner of the store placed the chairs in a window display that received the full afternoon sun, and I was dismayed to see, when driving past just a few months later, that the lovely violet color of the tape had faded to a most unattractive blotchy pink.
I have two suggestions for people who want to preserve the color of their Shaker-tape chair seats. First, choose subdued colors: white, cream or tan, for example. These seem less likely to appreciably fade. Next, protect the chairs from strong light.
It is possible to keep this material looking fresh for quite some time. In our living room, we have a chair seated with a checkerboard of blue and white, and it looks almost as good today as it did four years ago when I seated it. This is a result of two things: I applied Scotchgard to the seat after I finished weaving it, and we placed the chair in an area with relatively subdued light.
You might also try something I have done several times: weave the seat from splint, then prime it, and apply a couple of coats of latex enamel in a color of your choice. You’ll be amazed at how well the paint will hold up.
— Kerry Pierce is a regular contributor to Woodcraft Magazine.
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