Reacclimate after resawing?

[Eric DeSilva]

I've been experimenting with trying to resaw. Generally doing a pretty poor job, unless you think making two 1/4" thick boards from 4/4 stock is a good job. Part of the issue is the blade I was using--I've just taken advantage of the Laguna 3/4" blade offering, so I'll see if my 14" PM BS will do better with better teeth.

On to the real question. Are you supposed to let wood rest after resawing? If so, how long and why?

I always assumed that the internal tensions would be released as the thing is resawn. And I also assumed that acclimatized wood is homogeneous throughout, so it shouldn't have to reacclimatize after being resawn. I say that, but notice that the piece of bloodwood I resawed and then jointed/planed to square is now cupped. That particular piece of bloodwood was in my shop for close to two years, so I'm going to say it should have acclimatized...

[Stephen Edwards]

I've been experimenting with trying to resaw. Generally doing a pretty poor job, unless you think making two 1/4" thick boards from 4/4 stock is a good job. Part of the issue is the blade I was using--I've just taken advantage of the Laguna 3/4" blade offering, so I'll see if my 14" PM BS will do better with better teeth.

On to the real question. Are you supposed to let wood rest after resawing? If so, how long and why?

I always assumed that the internal tensions would be released as the thing is resawn. And I also assumed that acclimatized wood is homogeneous throughout, so it shouldn't have to reacclimatize after being resawn. I say that, but notice that the piece of bloodwood I resawed and then jointed/planed to square is now cupped. That particular piece of bloodwood was in my shop for close to two years, so I'm going to say it should have acclimatized...

In my limited experience of resawing, about 2 years now, I've had mixed results. As a rule of thumb, I now first saw the boards over sized and let them rest for a few days, or perhaps a week or more, even on boards that have been dry for 8-10 years.

Sometimes they don't move at all, other times there will be significant movement. I dunno why.

That's my experience and it has saved lots of frustration by doing it this way. Seems a waste of good lumber but I don't what else to do about it!

+1 for using a good resaw blade.

Good Luck!

[Joe Scharle]

Same take as Stephen; I've some walnut that was cut in 1942 and once in a while, I'll resaw a piece and it releases some new reaction.

[Van Huskey]

+1 to the prevous comments. I have had it happen, I resawed some cypress that had been cut well over 80 years and some of them went wonky on me. The were cut oversized so I just gave it a couple of weeks then milled it then a couple more days for the final surfacing, all was well after that. You would think after 80 freakin years it would have settled down, but noooo.

[Glen Butler]

While I do agree with the previous posters I also have to say that a thinner piece of would will be affected by slight moisture differences a lot more than a thicker piece of wood. Concrete can hold a lot of moisture. A thin film of condensation lies on practically everything, even if imperceptible to the human eye or touch. If you set these thinner pieces on something one side will be subject to higher moisture levels than the other side. Therefore cupping will occur in a smiley face orientation.

After you resaw make sure your boards are elevated at least two feet off any concrete and evenly supported using cinderblock and stickers. Your cupping problem just might go away.

[Howard Acheson]

Any boards I resaw, I stack and sticker for some period of time. The center of the board is hardly ever at the same EMC as the outer surfaces. When you resaw, you expose the center at a different EMC. This leads to the newly sawn boards wanting to warp as they acclimate. Stacking and stickering with a weight on top will keep them flat until they acclimate.

BTW, in almost all cases, a 1/2" resaw blade works best on 14" saws.

[Stephen Edwards]

BTW, in almost all cases, a 1/2" resaw blade works best on 14" saws.

I noticed a significant difference in cut quality and ease of cut when I switched from a 3/4" to a 1/2" Timberwolf POS 3 TPI blade on my G0555X. That change, along with using the "flutter method" for blade tension (I learned that tip here at SMC, too!) has most certainly made resawing more efficient for me.

[glenn bradley]

It sounds like you are preparing parts rather than rough resawing to sticker for later. When I prepare parts I do the following, others will have their favorite protocol:



Face joint board
Edge joint board
Plane board
Resaw with jointed edge down and one flat face against the fence using stacked featherboards, roller stands and all that for control
Set jointed faces on workbench and check for any excessive release
Re-face joint the previously jointed face only if required
Re-plane resawn face parallel with jointed face
Return to step 4 with the re-sawn, re-planed boards
Repeat till you're done

[Myk Rian]

Face joint board
Edge joint board
Plane board
Resaw with jointed edge down and one flat face against the fence using stacked featherboards, roller stands and all that for control
Set jointed faces on workbench and check for any excessive release
Re-face joint the previously jointed face only if required
Re-plane resawn face parallel with jointed face on
Return to step 4 with the re-sawn, re-planed boards
Repeat till you're done


Pretty much what works for me too.
I have some 100+ yr old pine that still wants to move.

[Steve Clardy]

Resawing 1 board in half, I usually clamp it back together for a few days. I usually reverse the 2 halves, depending on how/if they cupped.

[Cary Falk]

With my limited experience, I find that I usually need to sticker the boards in pile and clamp the whold stack down to prevent movement. I usully let it sit for a few days to a week. After that it usually behaves itself. I try to make sure when I do the final sizing I take off equal amounts from each side or I have to sticker it again.

[guy knight]

With my limited experience, I find that I usually need to sticker the boards in pile and clamp the whold stack down to prevent movement. I usully let it sit for a few days to a week. After that it usually behaves itself. I try to make sure when I do the final sizing I take off equal amounts from each side or I have to sticker it again.

this is what i also do with good results

[Jeff Nolan]

I think you pretty much have consensus on the acclimation question, however Stephen E. made a good point about blades. When I had a 14" bandsaw I really struggled with resawing until ran a 1/2" blade (I believe it was a Woodslicer but I am a big Lennox fan now). For resawing on a 14" I think the 1/2" is pretty well ideal insofar as blade width goes.

[Eric DeSilva]

Thanks for all the responses. I'll just start factoring rest into the equation and try to be more patient.

I've already ordered the 3/4" carbide blade and have heard others say good things about it. If I'm still messing things up, maybe I'll switch to 1/2".

[Kevin Guay]

I think that the issue is wood tension rather than moisture content (which is why it happens on old boards too). When you resaw a board, you cut fibers that are holding the wood together. This releases quite a bit of tension and can cause warping relatively quickly.

- Kevin
http://www.finewoodworkingindex.com