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For a little while, I've been buying longer Southern Yellow Pine boards at 'ye olde orange home center' that contains pith.

The idea is that I'll rip out the pith and some surrounding material and then leave a couple inches of more stable quasi quarter-sawn or rift-sawn boards. Considering the cost of the boards, seems like a pretty sweet deal if I can hack it.

I was able to do it a few times successfully. The boards I'd rip from the original 2x10 ended up being pretty stable, barely moving even after weeks after sitting out.

The problem though, is it's REALLY hard to rip. The tension in the wood causes it to bind almost immediately. Terrifying on the table saw, especially on longer boards.

I tried cross-cutting 8' boards with my smaller battery-powered circular saw, but sometimes that saw would bind.

I tried the bandsaw just now, put a ton of effort into setup and supporting an 8' board. The blade started to bind up and I smelled a little burning, so I cut the power.

Here's a picture of my latest attempt:enter image description here https://imgur.com/wEEDAOz

In this example, I started the cut initially on the table saw, didn't go well, then tried the bandsaw and the wood almost immediately closed up. Took some doing to free the blade.

I also left these boards in my lumber rack for weeks, maybe almost 2 months. I feel like it should be reasonably acclimated to the shop environment.

I've checked my power tools for square (table saw, bandsaw) and it's pretty spot on far as I can tell.

Am I missing something obvious? I realize wood tension is a thing, but I feel like it shouldn't be this hard. Is it me? Is it the wood?

Any help would be appreciated.

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  • Several thoughts using the bandsaw. 1) Make certain that you are keeping the board flush with the fence. 2) Try using a larger blade 1/2" or 3/4" with fewer teeth 3-5 per inch is more than enough. 3) Tru using a wedge on the board at the beginning of the cut to help keep the cut gap open.
    – Ashlar ♦
    Commented Jun 10, 2023 at 0:04
  • How many teeth on your tablesaw blade? Is it thin kerf? Are you comfortable stopping the tablesaw when it starts to bind and then removing the board and cutting again? Are you comfortable banging a shim in (with the motor off) and then continuing the cut? –
    – Aloysius Defenestrate
    Commented Jun 10, 2023 at 4:06
  • Consider making a first pass on the bandsaw freehand. Suppose you want to cut two 4-3/4" pieces from the 10"-wide board. Draw a line down the middle of the board, move the bandsaw fence out of the way cut the board freehand to the line. After the tension in the board has been released you may have to plane an edge of each board or run them through the tablesaw attached to a board with a known straight edge that is held against the fence. Then cut the opposed edge on the tablesaw in the usual way.
    – Cary Swoveland
    Commented Jun 10, 2023 at 23:22
  • BTW your efforts to acclimate the wood shouldn't go unacknowledged. Yes, almost two months should be sufficient to have reasonably confidence that the wood is acclimated or close to it. And kudos for waiting that long! (So many people don't acclimate at all, or think just a few days will do it.) One other thing that I feel someone should have asked about previously, you are sawing down these x10s/x12s because you need 8' lengths at the narrower widths, correct? If that isn't the case then crosscutting to rough length first is absolutely the right call; do this using a hand saw if necessary.
    – Graphus
    Commented Jun 12, 2023 at 7:17

3 Answers 3

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Wax your riving knife well with paste wax, see if it makes a big enough difference. If you don't have any paste wax just scribble thoroughly with the butt of a candle, same as is done on hand saws to reduce friction and prevent binding.

It's normal with this sort of thing to suggest checking the riving knife is parallel to the blade (as well as to recommend using a short fence, see Is a shorter rip fence safer?), but obviously the wood closing up and binding so severely on your bandsaw blade tells you the wood itself is mostly, or entirely, at fault.

That is in fact normal behaviour — not an everyday thing, but it's common enough that it should be expected a certain proportion of the time, although it's perhaps not usually this pronounced. The wood is likely 'case hardened', see Can it be predicted when a board will bind? for a little more on that.

Note the suggestion to use wedges to force the saw kerf to remain open, which is a tip that comes down to us from before the days of power tools, so we know this problem is by no means a recent phenomenon!

See also: Stress management on Wood magazine's site.

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  • I had been meaning to come back and update my answer and put in 'cleaning and wax' the riving knife, but a bit late for that.
    – bowlturner ♦
    Commented Jun 13, 2023 at 17:13
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Sounds unusual. I have no experience with SYP, but I find it to be a pretty easy go ripping 2x green lumber when compared to hardwood with a lot of internal tension.

Have you tried doing a 1/2 depth rip cut to relieve some of the stress? I’ve had good luck with that method in hardwoods that may have been questionably dried?

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  • Haven't tried that, but sounds like a good idea. Should I rip 1/2 inch on each side then finish the cut?
    – Ryan
    Commented Jun 9, 2023 at 20:29
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    When I dealt with some really case hardened walnut (6/4) I used that approach. I ripped it 1/2 the way thru (or thereabouts) flipped it ripped the other side. On the second rip, once it was about 1' through the cut I stuck something in the kerf to help keep it open. I have an MJ splitter on that saw, not a riving knife, so might be entirely unnecessary. This seems very labour intensive though!
    – John Carter
    Commented Jun 10, 2023 at 0:07
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    Perhaps another approach could be: rip half way through with the table saw and then complete the second half with the band saw? I would assume the wider table saw kerf would prevent it from pinching the bandsaw blade, and would be a safer operation if the wood is really case hardened.
    – John Carter
    Commented Jun 10, 2023 at 0:09
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Does your table saw have a riving knife?

Something like this?

enter image description here
From Amazon.com

These are supposed to help keep a board from pinching the blade when they are cut.

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    Yeah, it has a riving knife. When I say that the wood is binding, it's grabbing onto the riving knife, not the blade. There are no burn marks on the wood. Grabbing the riving knife makes it hard to move the wood through the saw though. It takes more force than I'm comfortable with.
    – Ryan
    Commented Jun 9, 2023 at 19:24
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    check that the riving knife is perfectly parallel with your blade. Having it off slightly can cause binding.
    – gnicko
    Commented Jun 9, 2023 at 20:01
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    O_o Answers should not have any questions in them that actually require an answer. Clarification questions are what the Comments are for!
    – Graphus
    Commented Jun 10, 2023 at 7:18

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