If you are an accomplished finisher, stop reading right here. There’s nothing for you below. I hear there are some funny new movies of monkeys ironing linen shorts at YouTube.
This week I’m applying many thin coats of varnish to a chest of drawers that I’ve been building during nights and weekends at my shop at home. The finish recipe is my favorite for black cherry: First apply a coat of boiled linseed oil, let the project sit in the sun and allow the oil to cure in a warm room for a week or so.
Then wipe on thin coats of a satin varnish that has been thinned with low-odor paint thinner (also called mineral spirits). I like three parts varnish to one part paint thinner. Sand between each coat with a broken-in #180-grit sanding sponge. After about six coats, the result is a warm and durable finish. It takes time for each coat of finish to dry, but that gives me time to write, sharpen and tune up the machines for my next project.
This weekend I stumbled into two small details that make this finish easier. The first detail concerns the sanding sponge. When sanding each coat, the process creates a fine powder all over the project. With varnish, I have found it best to remove this powder before applying the following coat (it’s not as necessary as when you use shellac or lacquer because those finishes dissolve and bond to the coats below).
I like to use a tack rag to remove this dust, but I am tackless this weekend. So I started thinking about tacky things in my shop. I half-pondered even making my own tack rag. Then I looked at my 3M sanding sponge.
Hmmm. One side is abrasive. The other is a sponge. Duh, I wonder if the sponge side would pull up the powder? It does indeed, and quite well. And when the sponge becomes loaded you can wash it out and renew it. I can’t believe I’ve been using sanding sponges since “Silver Spoons” was on television and never thought of this.
Second detail: Gloves. Whenever I work with solvent, even paint thinner, I like to use gloves. It makes clean-up easier and I worry less about what danger is lurking on the solvent’s MSDS. Usually I use latex gloves from a big box store for mild solvents. I have always hated these gloves because they fall apart while I’m applying the finish and leave little bits of latex behind. I’m sure there are better-quality latex gloves out there, but not in my local stores.
A few weeks ago Managing Editor Megan Fitzpatrick gave me a bag of blue nitrile gloves, which are made using a synthetic polymer. These gloves were made by the same company that makes my latex gloves, so my expectations were low.
Boy was I wrong. The nitrile gloves are far more durable. I’ve applied four coats of finish using the same pair of gloves and they are still going strong without a single tear. Farewell latex.
— Christopher Schwarz
Chris,
After the linseed oil has cured for a week, do you wipe it down or anything before applying the satin varnish?
Peace,
Jason
Jason,
There’s nothing to do after the linseed oil has cured except apply the varnish. It doesn’t tend to raise any grain or harden any significant dust nibs.
Chris
Nitrile gloves are great for those with latex allergies. Yes, some people’s skin does react to latex exposure.
I love the "smurf gloves" and use them daily in my work as a diesel mechanic. I’ve tried black nitrile gloves, but found them less durable than the blue ones. I go through a box of them every three weeks or so. They also work well as temporary covers on certain things. Jars, cans etc.
I use (and reuse) the blue nitrile gloves too. You can remove them carefully and pop the fingers back out by blowing into the glove.
I used one last night as a temporary cover on a disgusting-science-project-of-a coffee cup that needed transporting to the kitchen for proper decontamination.
I thought everyone knew about nitrile gloves by now.
They’re not proof against everything though, so it’s probably best to check out a glove selection chart just to see what’s best for various shop chemicals.
Sounds like a neat idea for removing sanding dust between coats. My favorite method involves wiping the surface with a rag from a clean old cotton T shirt that is just slightly damp with water. The water in the rag is strongly attractive to the particles yet will be completely evaporated from the prepared surface within a minute after wiping.
I am sold on the micro fiber tack clothes. I use them for
everything around the house.
Steve
Chris, what is that 45-degree thin, pale line on the edge of your top? It’s just to the right of 3M pad in your first photo and between the second and third fingers from the right on your discarded latex glove. Is this your glue line? If so, why the 45-degree cut? Do you always glue your tops this way?
I discovered the blue nitrile gloves in my local farm/fleet store in the "veterinary supplies" section. Amazing what you can find if you’re willing to look in the wrong place!
Nitrile gloves are the one and only thing I buy at Harbor Freight. When you catch them on sale you can pick up a box of 100 for about $7.
Hi Chris,
latex is not durable under the influence of oily substances like mineral spirits or even linseed oil. That explains why your gloves have expired while working. Latex is fine for alcohol (Shellack) or even acetone.
Regards
Marcus