Finish question?

[Mike Shoemaker]

I made up a box for a friend. Aromatic Cedar. It was small, 17X5X3. I coated it in poly. When I was done it had these "blotchy" areas. I thought I sanded pretty well. It was like the poly was showing every little defect. And a couple of areas looked like there was nothing on it? I just stripped it and gave it to him natural. Any suggestions?

[Russ Filtz]

No idea, never worked with it. Maybe the "aromatic" portion did you in (oils?), causing the poly to pool around the oils? Maybe just try an oil finish like tung or BLO?

[Jim Grill]

Hi Mike,

I have never worked with that type of cedar either. You might try a light coat of shellac first. A one pound cut with a rag followed by a light rubbing with a fine non-woven abrasive pad. Just be careful not to rub through it.

Shellac is great for sealing or for using as a base between dissimilar top coats. You can even apply an oil stain over a light coat of shellac, which is a great technique for soft or open grained woods that tend to blotch when stained.

[Howard Acheson]

I made up a box for a friend. Aromatic Cedar. It was small, 17X5X3. I coated it in poly. When I was done it had these "blotchy" areas. I thought I sanded pretty well. It was like the poly was showing every little defect. And a couple of areas looked like there was nothing on it? I just stripped it and gave it to him natural. Any suggestions?

How many coats did you apply? More than one?

What was your sanding schedule? What grits?

[Mike Shoemaker]

I sanded with 120, then put one coat on.

[John Mihich]

I always sand at least to 150 sometimes as high as 220 when applying a finish w/o a stain. You need at least 2 coats of poly, probably 3-4. The first coat will be uneven. Lightly sand between coats with 220 - 300 grit. Then apply another coat. Two might work but three is probably best. For most poly projects I use a wipe on. For that it may take 5-6 coats.

[Howard Acheson]

Mike, sanding to 120 is not enough. You should continue with 150 and then finish with 180 grit. If you are using a sanding machine, after sanding to 180 grit with the machine, hand sand with the same grit with the paper on a sanding block. Sand in the direction of the grain to remove all the last vestiges of the prior sanding marks.

As for finishing, one coat is never enough. The first coat is almost totally absorbed but it is also absorbed unevenly. That's just a function of wood. Some areas are more absorbent than others. After the first coat has fully dried, sand it with 320 paper on your sanding pad. Dust it off and apply another coat. With most finishes, three coats are best.

[Mike Shoemaker]

Thanks Howard, this is my first attempt at putting a fifnish on anything.

[Richard M. Wolfe]

Mike, I'm a little late in posting but will throw in my two cents. I've made a number (probably around fifty) cedar chests. You picked one of the toughest woods to finish. With the grain changes and knots it can be a bear.

The last one I made is in the shop and ready to go....finally. I put five coats on it. The knots soak up finish like a sponge and you just have to keep putting stuff on. I sand to about 150 and then put on the first coat. I use oil based floor sealer as it's cheap and tough...any kind of varnish will work. Try to get it on pretty heavy but beware of runs. The next day I lightly sand and scuff with #0000 steel wool and put on a second coat. There will be areas that are sealed pretty well so it takes a while to dry on them. I wait at least two weeks before doing anything else. Check it and if there are still dull flat areas another coat is called for. After letting the base coats fully cure I sand and steel wool lightly and go on with a good quality thin wiping varnish. Hopefully I'm finished by then.

A word of caution if you work more cedar. I don't put finish inside the box as it will defeat one of the pluses of cedar - it's odor. Also leaving one surface open will let the oils escape. I never tried sealing aromatic cedar all around but it might cause problems like the next sentence - which I have done. Don't put any finish where surfaces will come in contact, like where the lid closes on the body. The oils will bleed out and turn the finish into a gooey mess. (Don't know what would happen with water based as I've never tried it). Spraying with lacquer would probably speed up the process, but I don't have a place where I can safely (for the wood and me) spray.

By the way, I don't know of anything you can finish with a single coat.

Hope this helps.

[Mike Shoemaker]

Thanks for the info. This was the first time I tried to finnish anything. The advice about sanding and mulitible coats is important stuff. I'm looking at getting some books.