Sanding or planning?

[Osvaldo Cristo]

I learn something new today: planned wood is more water resistant than sanded one.

https://youtu.be/7PCOZkByBDg?t=15m27s

I would like know your experience also. Thank you in advance for your feedback.

All the best,

[Warren Mickley]

I have done this experiment also. A drop of water on planed wood will sit on the surface much longer. Probably the quality of the planing plays a role.

I once put a tablespoon (15ml) of water on a surface that had been planed and shellaced. The next morning there was a small drop left; none had penetrated. I think the quality of the application played a factor because others report shellac not to be water resistant. Maybe the quality of the surface underlying the shellac is a factor.

I suspect that white pine, Pinus strobus, that has been planed and painted will take the weather better than that which was machined and sanded.

[Brian Holcombe]

I feel the same, planed surfaces have been more durable against water for me. Outdoors they seem to retain color longer than sanded wood. I take that as an indicator of how quickly the surface is affected by the weather.

[Tom M King]

I did a small experiment on the Cypress shingle roof I installed a couple of years ago. On one bottom row, above one of the porches, I hand planed a few shingles, and left some roughsawn, side by side. I marked the ones that were planed. I forgot to check the first season when I went up there to clean the gutters, but did check this past late Fall. I didn't put water on them, but did feel the surfaces. The hand planed surfaces were no longer slick, but still show a difference in texture to the sawn surfaces.

I'll try to remember to take some water up with me next year, but am not expecting to see any difference in water absorption. Heart Cypress shingles don't rot, unless a layer of tar paper is put under each row, but they do weather away very slowly.

Shingles that I've found that were over 100 years old, that started out at almost an inch thick at the lower edge, have weathered away to only about 1/2" thick on the lower edges. A straight edge laid on the top of the whole shingle shows the amount of weathering. That's fooled a lot of people into thinking that they were thin to start with, and probably why you see so many thin reproduction shingles on old houses. In any case, I don't think the surface texture would have had any noticeable difference in the total life.

One roof I found that was made in 1850 had a mix of sawn, and split Cypress shingles. End of life for that roof was 1982 (because of remodeling), and neither type was showing any difference in edge thickness after that time.

[Al Launier]

Interesting thread. Hadn't any thought to this, but it does make a lot of sense when considering the microscopic surface produced by each method.

[Dave Parkis]

My woodworking club brought Garrett Hack in to speak a few years ago. As part of his presentation, he planed a panel and then sanded half of it. After that, he took a cup of water and poured it onto the panel. The part he sanded absorbed the water, but the water just beaded up on the planed half. One thing to co side is that some folks claim that planed surfaces don't accept stain as readily.

[Jim Koepke]

One thing to co side is that some folks claim that planed surfaces don't accept stain as readily.

Could that be a factor of the surface tension of the stain?

My work is mostly planed with little or no sanding. It seems to take most of my oil based stains quite well.

jtk

[Brian Holcombe]

I’ve stained things that have been planed. It stains evenly.

[Mel Fulks]

I don't know a lot about finishes, but aniline stains go on differently smoothed surfaces pretty evenly. The oil stains are darker on sanded wood than planed wood. I think everyone who has worked in commercial shops has seen many do overs
with oil stains. Some of the state and municipal buyers will accept anything.