Dimensioning with Scrub Plane - a bit from each side?

[Ryan Michel]

Background:
Recently I took a piece of ~4/4 down to 1/2" and started with one side as the "face side" (flat/hollow, no wind) and chunked away at the other side close to my scribe line.

What I found was that the "face side" was no longer flat and developed a twist.

I know that with machine planers, one must take a bit off each side all the way down to final thickness, I am now guessing the same is true for hand planes (i.e. the board doesnt care how it's being dimensioned).

My Question:
When removing a lot of material is the process to use the scrub to chunk away off each side gradually down to an approx thickness and then work on a face side followed by a scribe line and final dimension?

I have searched through a lot of books (have a local library with a TON of hand tool books) and none that I have found address this issue. I have also searched the net with no luck.

Thanks for the help.

Ryan

[Frank Drew]

Ryan

You answered your own question -- the wood doesn't care how it's being dimensioned and will move if it wants to. It's always safer to remove roughly the same amount of stock from both sides of a board, and if I'm being extra careful (or extra paranoid!) I won't even do all the dimensioning on one day.

[Mark Stutz]

Precisely! Whether by hand or machine, I never bring anything to final thickness on the first go. If it moves too much after the first rough thickness, I even get concerned that it may move further after the next , and sometimes will look for different stock, depending on how much extra thickness I have.

Mark

[Pam Niedermayer]

Seems very wasteful to me, that's 1/2" of wood trashed. Wonder what would have happened if you'd sawed or rived it to 5/8" before planing it to finish thickness.

Pam

[Robert Rozaieski]

I agree with Pam. I would recommend resawing if you need to go from 4/4 to 2/4. Not only does it waste less wood, it's easier and faster than trying to hog away 1/2" of wood with a plane.

[James Mittlefehldt]

Having used a scrub plane I can say with confidence that in my humble opinion Robert and Pam are right, resaw to 5/8 and them plane it to final thickness, taking that much off with a scrub plane sounds like way too much work.

To be specific I have a sandvik rip saw that I would use for that operation, and have done in the past.

[Tim Leo]

A 4/4 board is 1-inch thick before it is surfaced. The 4/4 boards I buy at the lumberyard that are surfaced on 2 sides are only 3/4-inch thick. Bringing that down to 1/2 inch thick means removing about 1/4-inch...not enough to resaw...unless you can use the veneer.

[Frank Drew]

Pam, Robert,

Since resawing removes wood from only one side it can subject the resulting board to exactly the forces that could caused Ryan's original board to warp. And I'd certainly be shocked if after resawing the scant 3/8" offcut didn't move one way or another, and then what have you saved?

James,

Do you mean you use a Sandvik hand saw for resawing, or a Sandvik ripping blade on a band saw?

[Robert Rozaieski]

A 4/4 board is 1-inch thick before it is surfaced. The 4/4 boards I buy at the lumberyard that are surfaced on 2 sides are only 3/4-inch thick. Bringing that down to 1/2 inch thick means removing about 1/4-inch...not enough to resaw...unless you can use the veneer.
I beg to differ, I did just that for the back boards of a recent cabinet back. The resawn 3/4" pine from the BORG finished off at about 7/16" for the thick piece and a hair less than 3/16" for the thin piece. If you can saw a straight line there is very little cleanup with a hand plane required and very little waste is created.

http://farm3.static.flickr.com/2250/2400943668_c8fc919395.jpg?v=0

http://farm3.static.flickr.com/2131/2400943676_07de17f467.jpg?v=0

[Robert Rozaieski]

Pam, Robert,

Since resawing removes wood from only one side it can subject the resulting board to exactly the forces that could caused Ryan's original board to warp. And I'd certainly be shocked if after resawing the scant 3/8" offcut didn't move one way or another, and then what have you saved?
If it's going to move, then it's going to move whether you plane or resaw. In these cases, your best bet is just to use a different board. I think the point is that it's simply faster, easier and wastes less material to resaw if your board is stable enough and doesn't have a lot of built up internal stress. I think Ryan's board had too much internal stress as it sounds like it moved immediately and not say when he came back the next day.

In order to resaw or plane a board down in thickness with minimal movement, the board should be stored in the shop environment long enough to equilibrate to the shop conditions. This could take a week or it could take several years depending on the dimensions of the board, the species and whether it has been kiln dried or air dried. Once the board is stable and equilibrated to the shop conditions, there should be very minimal movement whether you remove lumber from one side or both sides, unless there is a lot of stress built up in the board. If there a lot of stresses in the board, then no amount of equilibration or equal removal of material from each side is going to prevent the board from moving once you start planing or sawing. Sometimes you just have to take a mulligan and start over with another board. The warped board can probably be cut up for use elsewhere.

I should also mention that if your shop is in a garage, basement or anywhere where the humidity is drastically changing from one day to another, then the board may never equilibrate. In these cases, it's best to bring the board to thickness and complete the joinery all in the same day before the piece has a chance to move. If you can't use the thicknessed board(s) the same day, sticker them between two flat cauls with weight on top to help keep the boards flat until you can use them. But again, if there is a lot of stress in the board, this won't make any difference.

[Frank Drew]

Robert,

I certainly don't object to the idea of limiting waste, but in my experience all those "saved" pieces just add up to clutter, and I'm a guy who never willingly threw a nice piece of wood away, no matter how small (so I had lots of clutter). Unless you have a ready use for all your 3/16" thick offcuts from resawing they end up in a corner with all the other small odds and ends that would make nice drawerfronts, or whatever, but usually just gather dust and get in the way.

The point about reaction wood is that you don't know it is until it does, and over a number of years in the business I found that it was cheap insurance to approach final dimension of critical pieces in stages (including removing stock from both sides) to lessen the risk of losing the entire board.

I always brought the material for a job into the shop way ahead of time to allow the wood to reach an equilibrium with an indoor environment, but still, things happen, and I found that safe was better than sorry.

By the way, I applaud your hand resawing skill.

[Robert Rozaieski]

I agree, bringing it to final dimensions in stages is the best way to account for unpredictable stresses, whether you resaw or plane. As you say, one cannot know the extent of the internal stresses until you start dimensioning.

I admit I am cheap and have a problem throwing cutoffs out if there is the remote chance I might have a use for it in the future :D. I also agree that I get a lot of pieces that end up collecting dust, and these eventually end up in the fireplace (the hardwood ones anyway) when I decide it's time to clean out the scrap bin. A lot of the thin scrap comes in handy though. I use a lot of it to make wedges for through wedged M&T since it's already to thickness. They also make nice drawer bottoms if they are not too thin or small. And the thin pieces can also be salvaged for inlay/marquetry, etc. Or veneer as you mentioned.

A real neat way to use up thin offcuts from resawing is to make letters like the ones you pay $2 apiece or more for in the craft store. If you prime and paint them you can use a mix of woods. The kids like the plaques with their initials or name for their bedroom walls. You can even let them get involved by doing the painting. :)

[James Mittlefehldt]

Pam, Robert,

Since resawing removes wood from only one side it can subject the resulting board to exactly the forces that could caused Ryan's original board to warp. And I'd certainly be shocked if after resawing the scant 3/8" offcut didn't move one way or another, and then what have you saved?

James,

Do you mean you use a Sandvik hand saw for resawing, or a Sandvik ripping blade on a band saw?

Sandvik hard point saw filed rip, what's a bandsaw? I do it the way that Robert shows.

As to the original post when someone says that they are working with 4/4 stock my assumption is and was in this case that he has one inch thick rough lumber. Had he been working with S4S stock than he would I would assume state it was 3/4.

[Ryan Michel]

Thanks all for the discussion. I should have mentioned that the board is 4/4 S2S, so it is about 3/4 inch thick.

I recall Rob Cosman saying in one of his teachings that resawing a small board would yield 2 unstable pieces so one should work to final thickenss with a plane (this may be badly taken out of context - I think it was in the drawer making DVD).

I will be approaching final thickness from each side on this next go with the same board, I'll update the thread if I see a big difference.

Ryan

[lowell holmes]

Showoff! :-)