Adding a finish before you assemble a project not only saves you a lot of aggravation but also helps you achieve better-looking results.
The hardest part of finishing a project with lots of joints is getting consistent coverage on every surface, including all the nooks and crannies. And it can be a real headache to get into those places to sand the finish between coats.
Sometimes it makes more sense to apply the finish to the parts individually, before putting them all together. That’s the idea behind prefinishing your workpieces. Before assembly, you can easily access all sides of every part and apply an even coat of stain or any finishing product. And if you need to buff them down between coats (as so many finishes require), that’s easy as well.
HANG ‘EM HIGH.
But prefinishing presents a new challenge — what to do with the pieces when they’re wet. For large panels or tabletops, you can apply the finish to one side, let it dry, and then flip it over to do the other. But how do you deal with lots of smaller parts?
Over the years, I’ve come to rely on a simple but very effective way of hanging wetfinished parts on a line in my shop. It’s a lot like drying clothes on a clothesline. It might not look like an elegant solution, but it’s very effective. And best of all, it’s inexpensive and works well, even in a small shop.
PREPARING THE PIECES.
Since most finishes will interfere with a good glue bond, it’s important to keep surfaces that will be glued (like mortises and tenons) clean. So, the first step is to mask off the areas you don’t want finished.
I often fill mortises with small bits of foam backer rod cut to size. You can tape off tenons using painter’s tape. (It’s easy to remove when the finish is dry). The box on the opposite page will show you how to mask parts effectively.
But as you get used to this method, you’ll find you don’t always need to mask these surfaces. That’s because you have so much better control when applying the finish to a single, flat part.
 |
| Simple and inexpensive hooks can be used to hang parts while they dry. |
ADD THE HOOKS.
The next step is to attach a small hook to each part. The trick here is to locate the hook in a spot where the hole that is left behind won’t be seen. For example, a hole in the end of tenon will be out of sight, buried in the mortise. Chair or table legs can have a hook in the bottom where the hole will never be noticed. If you think about it, virtually every individual piece has a surface that won’t be seen when assembled.
Now all you need to do is drill a small hole and add an appropriately sized hook that can handle the weight of the part. In most cases, a hook like those shown in the margin photo at the bottom of the opposite page will work fine.
A WORKSHOP CLOTHESLINE.
Next, you’ll need to install a line in your shop to hang the pieces on. In a garage shop, an easy option is to use the overhead rails from your garage door. There’s usually plenty of room for a couple of lines strung between the ends of the track. But you can also string a line between two walls easily enough.
For the line itself, I’ve used both nylon cord and thin picture-hanging wire with no problems. The important thing to keep in mind is that you don’t want the pieces sliding into each other as the line sags under the weight.
When using a cord, it’s a simple matter to tie a slipknot every four to six inches. For a wire line, you can just wrap a little tape around the wire every few inches to stop the hooks from sliding.
 |
| Adding a few simple slip knots to a nylon line keeps the hanging parts from bumping into each other while the finish dries. |
STRATEGY.
After you’ve attached the hooks and masked the parts, you can brush, wipe, or spray on the finish of your choice. And you’ll have plenty of time to check for runs, sags, and other imperfections.
All you need to do now is hang the pieces up to dry. I like to finish all the pieces by size, starting with the larger pieces first. This way, I can distribute the weight on the line to prevent it from sagging too much. Hang heavier parts near each end (where there’s more support) and lighter parts in the middle of the line.
 |
 |
| The first joint has a buildup of stain in the corner. | The second joint was prefinished and has a more even coat. |
Another benefit of this technique is that you can easily inspect each piece for finishing flaws while it’s drying. And when it’s time to sand between coats, you’ll really appreciate how easy it is to work with smaller, individual pieces. Once you get used to the process, you’ll be prefinishing almost all of your projects.
Masking for Trouble-Free Assembly
One thing you’ll want to avoid when prefinishing is contaminating joints with stain or finish, potentially weakening the glue bond. An easy way to do this is to mask these areas on each piece.
 |
 |
For tenons, it’s simply a matter of using a strip of painter’s tape to mask the part. You don’t need to worry about the shoulders, since they provide very little strength when glued.
To mask a mortise, I like to use strips of foam backer rod. It’s easy to cut to size, and it keeps the finish out.
