How to deal with twist? (longish)

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Hello All,
First off, note my moniker :^)
Second, please no replies of "buy a jointer." :^)
OK, specific scenario: yellow poplar, 4s4, 1x8. I've cut it to length (30") and am ready to rip my widths (3"). Laying it on the TS, there is noticeable twist - I'd say 1/8" to 3/16" across two diagonal corners (push down one corner, the far opposite rises off the table 1/8-3/16")
So, how big a safety issue is this to go ahead and rip? Blade guard/splitter/pawls all in-place. I went ahead and did it and got enough resistance as the board began passing the splitter that I actually shut the saw down and manually pulled the board back out; could see that the wood was closing up after the kerf, though it didn't seem that it would have been enough to cause the resistance I got; regardless, flipped it end-for-end and completed the cut w/o incident. The 2nd rip from the ~4-1/2" cutoff went cleanly.
That's the safety question. I DO realize that piece I was cutting for is now not "perfectly" flat nor with "perfectly" square edge/face corners. Eh, it might not matter in my specific case, THIS time, for THIS project. BUT. How much twist do you tolerate before you either work to correct it, or select different stock?
I fully admit that I'm completely susceptible to TAS - Tool Acquisition Syndrome. Yet, because my moniker is what it is, I'm far from having carte blanche from SWMBO :^) Jointer has to wait.
So, where do I go from here? I don't want this to devolve into a "how flat is flat" debate. I'm just looking for thoughts on how to work with what I have - TS (GI 50-185L), 3-1/4hp plunge router, CMS, various bench-top and hand-held sanders.
Thanks, Chris
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When ripping stock like that, keep steady pressure in one area to prevent the board from rocking back and fourth as it is passing through the blade. As far as tolerances for twisted wood, it really depends where the board is going in the project. If it's a cleat or something, I'll let a little warp go. Anywhere else and I prefer flat as possible. Crooked stuff doesn't fit together well, and If I'm gonna take the time to build something, I'm gonna do the best job possible. As a compromise on a jointer, I'd look into a good hand plane or two, like a Stanley #7 or similiar. These were used for flattening/jointing boards before power equipment, are still in use, and readily available at most flea markets, auctions, etc. --dave

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Dave Jackson wrote:

Thanks for mentioning this, Dave. I forgot to say that I did do this - before I ripped, I noted the corner of the board nearest to me (standing left of blade) was naturally "up." I made sure it stayed that way thru the cut.

All understood. ... and I guess it comes with experience as to what "flat as possible" is for the application. -Chris
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Well, OK, but that's the best tool for dealing with it. If your budget or your shop space won't accomodate a jointer, then get a good hand plane and practice using it.

Too much twist for comfortable table saw use IMHO...

Big. As you found out.

Good thing you did what you did. That was a kickback just waiting to happen.

None at all if I'm going to run it through the table saw.
If I'm going to rip it on the band saw and then joint it flat before planing it and taking it to the table saw, the acceptable amount of twist depends on how thick the rough board is, and how thick I need the finished stock to be. For example, if the rough board is 1" thick and I need 3/4" finished stock, then any twist much over 1/8" is unacceptable, regardless of width or length, because it doesn't leave enough extra for jointing and planing.

Hand plane(s) and a band saw. It's not safe to rip twisted stock on a table saw.
-- Regards, Doug Miller (alphageek-at-milmac-dot-com)
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First, get a new moniker; this one's holding you back.

Borrow?
I've had straight boards do this to me, too. There were internal stresses being relieved by removing the material in the kerf, so the opposing sides were free to move into that space. Like you, I shut down the saw in the middle of the cut. I took a small piece of slightly larger-than-kerf-thickness stock and wedged it in the gap. Then I could start up the saw again and finish the cut. Unlike you, my board wasn't doing this because of twist, so it wasn't rocking into the blade.
Maybe someone else with more experience can tell me this idea is okay, or really bad. It didn't "feel" so bad, and gut feeling counts in this business. I do my best to stand out of the line of fire; I was hit in the chest by a kickback once, a smallish board maybe six inches long by a screwy 3/4" thickness. It hurt way more than I would have expected, so I'm not anxious to ever have a repeat performance. Don't fear them, but maintain your respect for your tools.
The times I have used boards with twist I spent two or three times as much effort on the project as I would have with straight boards. Now I'm more willing to pay to have my wood milled at my source, and eventually will acquire the (power) tools to do it myself. I enjoy my hobby more this way. Last summer I built a firewood stand out of some twisted PT 2x4s. Thinks me, "I'll just pull these together with deck screws, no problem." Riiiight. In one spot the screw just tore into the wood. In another it started to split a chunk off. I eventually got it all together, but probably used $5 worth of screws and an extra hour of labour. Pretty hard to tell if it was worth it, monetarily, but I'm not proud of the result.
Sorry for rambling like this. Hope you get something out of it.
- Owen -
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Or rent?
There's a shop here that rents time at (last time I checked a couple of years ago) $25/hr to use everything except the *big* resaw bandsaw.
--
"The thing about saying the wrong words is that A, I don't notice it, and B,
sometimes orange water gibbon bucket and plastic." -- Mr. Burrows
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Owen Lawrence wrote:

Nah, it's more just to signal my level of experience in this forum. I won't let it hold me back.

Mmmm, might be a possibility.

Interesting solution on your part. But illustrates that it can happen even w/ a "flat" board. Grain, knots, compression/tension. All sorts of joyous variables.

As do I.

But how do you ensure that what is "flat" when milled will stay that way? You can't, I don't think. I can buy rough sawn lumber in town at a place that mills their own (alot of urban reclaimed trees). ... do you sticker rough sawn that you buy and bring back to your shop? I've had boards apparently twist after I get them home; I know, differences in RH/temp. Is there a way to minimize that based on how I store/stack 'til I'm ready to use? Or just buy them essentially right when I'm ready to start cutting, is probably the right answer.

No problem at all. I appreciate people taking the time to answer. -Chris
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You can't *guarantee* that milled stock will stay flat, but you can sure improve your chances a whole lot.
Start by selecting stock that's straight-grained, free of defects, and already reasonably close to straight. If it isn't straight in the pile in the lumber yard, it isn't going to be straight in your project either. Crazy grain is often prone to warping. Wood will definitely warp in the vicinity of knots and other defects; and sometimes defects are caused by internal stresses in the wood that will cause further movement after the wood is milled.
Quartersawn lumber is much less prone to movement than flatsawn lumber (and often presents *very* attractive figure besides).
Allow the wood some time to reach equilibrium moisture content (EMC) in your shop (or in your home, if the humidity in the shop differs considerably from that in your home) *before* you mill it. In the winter, this may be as little as a few days; in the summer, it may take several *weeks* before wood brought from a non-climate-controlled warehouse into an air-conditioned home reaches EMC. Stack it, stickered, while waiting for this to happen.
When you mill it, leave it about 1/8" over finished thickness and 1/4" to 1/2" over finished width. Stack it, stickered, again, and wait a week. Any pieces that have moved substantially in that time should be discarded, because they'll likely continue to do so. Slight movement (e.g. 1/32" bow in a 3-foot piece) should be jointed out, and the pieces milled to finished thickness and width.
Also, while jointing and planing, both in the initial and final phases, remove approximately equal amounts of wood from each side of the board. That helps to balance internal stresses, and minimizes the degree of movement.
-- Regards, Doug Miller (alphageek-at-milmac-dot-com)
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I've been buying most of my lumber kiln dried, rough cut. The guy I buy from used to be a wood grader for the government, and I trust his knowledge of wood implicitly. The first few times I brought my wood home, though, I stacked it heavily on the floor of my basement shop. Until I make a woodstand, I've taken to standing my boards vertically. There's just too much moisture sucking up right through the basement floor, and I've learned that if I leave my wood near it (not even on it), the boards are going to warp. Standing them on end has helped a lot.
- Owen -
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Chris,
How much twist is acceptable from a safety standpoint? Or how much twist is acceptable in your project?
You should keep in mind that a board could have internal stresses. You could have a board that sits completely flat on your TS before ripping it only to have 3 twisted boards by the time your done.
I've had good success using a planer to flatten a board (http://www.taunton.com/finewoodworking/pages/wvt095.asp ). I used this method to flatten a board in prep for resawing only to end up with two twisted book-matched panels when I was done. Ho hum.
If you don't have a thickness planer I would go for the hand-planes as people suggested.
-Miles
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TheNewGuy wrote:

snip

Chris:
PLEASE have a look at at least the first two pages of this kickback stuff. You dodged a bullet this time. Please don't press your luck. Bad habits start with a lucky first experience, and, when it comes to spinning carbide teeth, can lead to nicknames like Stubby, Squint or Oh That Poor Man. Wood is relatively cheap compared to a trip to the emergency room and the folllow up rehab cost.
http://home.comcast.net/~charliebcz/KickBack1.html
If it don't feel right before you do it take some time to think things through FIRST. Often there's a safer way to get it done. Ignoring that little voice in your head is a bad way to start when power tools are involved.
KNOWLEDGE IS POWER (but only if you use that knowledge).
charlie b
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> http://home.comcast.net/~charliebcz/KickBack1.html
great site - well worth reading Went through all of it. A great refresher if you know the stuff and even better reading if you don't know the stuff.
I had one small piece go flying -- once. But rule one is stand to the side. Since I routinely follow all these rules I was well to the side. Never could figure out how it happened. Went through everything after word. Assume vibration moved it a hair and gunk was on the blade. Now I clean blades before each project and check them before each use.
charlie b wrote:

--
Will
Occasional Techno-geek
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charlie b wrote:

Thanks Charlie. Read it, alot of good stuff I'm familiar with, and some new things to think about / check.
-Chris
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TheNewGuy wrote:

If you don't have a planer or a jointer, buy a jointer. If you have a planer, you can use some frigged up hack half ass method to simulate jointing with the planer.
The "buy a hand plane" suggestion is not nearly so simple as it sounds on the surface.
* buy a hand plane * learn how to tune it up * buy sharpening gear * learn how to sharpen
It was suggested you can find a #7 at a flea market or something, but it probably ain't that easy. Big planes, jointer planes, are hard to come by. When you can find one, they're usually significantly expensive. More power to you if you're the rare exception to this rule.
Then there's the fact that planing twist out of a board with hand planes is a skill that takes some time to acquire. I bought a mechanical jointer because I SUCK at this job. Making curlies is fun, but I found ruining perfectly good wood while acquiring a rather tricky skill was not very gratifying or encouraging.
I would further suggest that you not buy a benchtop jointer. Suck it up and buy a real one. I bought a Delta ShopMaster benchtop with aluminum tables, and it's only slightly better than nothing.

You can do a fake frigged up hack job of jointing with a router if you have a router table. I haven't tried it, but it's well-documented.
If I were you, I'd push SWMBO for the jointer anyway though. Once you can work with real wood (which is IME rarely flat enough, or twistless enough to go straight into a project) you can impress SWMBO with your new walnut dingleflootchie or cherry doily oiler or whatever. Being able to escape from BORG's crappy, overpriced lumber was a real epiphany for me as a woodworker.
I got there with hand planes initially, sort of, but the material acquisition curve for equipping yourself with hand planes is pretty steep, and then they're hard to use for this job. You will still need at least a plane or three if you don't have a mechanical planer, but you can get by with a lot less accuracy IME if one side is mechanically flat and both edges are mechanicall square. (Joint a face, joint an edge to that face, rip the other edge, then hand plane the remaining edge "close enough.")
Having said all that, my jointer really is a POS that's barely useful. I really need to replace it with a real one with cast iron tables and a sufficiently long bed to handle boards longer than 24". Such a beast would be more weight than my floor can take where I'd have to put it, and I can't afford one either. I may well wind up having to suck it up and master jointing by hand before it's all over in spite of everything I just said. I do NOT recommend one of these benchtop jointers as an answer to this question. They suck mightily.
--
Michael McIntyre ---- Silvan < snipped-for-privacy@users.sourceforge.net>
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Silvan wrote:

Yeah, I have neither, and I'm saving for a (non-benchtop!) jointer.

I believe that, but it also might be just what I need to do in the interim.

Edge jointing, yes, I'm aware, but haven't tried yet. I have some 2s2 pieces that I will be going this route (pun!) on.

I know that! Boy, the 2s2 figured sweetgum/liquidambar I got at the small mom&pop mill was a better deal than the boring 4s4 yellow poplar from the BORG.

I think you meant, "the remaining face," but I got it.
Thanks, Chris
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(Snip) - Big planes, jointer planes, are hard to come by.
Heck Silvan, I must be the rare exception. I was out at a few flea markets last weekend and between several of them, I could have bought a complete set of Stanley hand planes from a #2 all the way through a #8 with several half sizes and other scraper planes, scrub planes and spokeshaves, etc. I came across several #6 and #7 in pre WWII, good condition for around $50. One #7C was *exceptionally* nice for $75. (I might go back for that one.) Most of the other ones, #3-#5 good condition, for around $30. The most expensive one was the #2, at $150. I found plenty to choose from and ended up bringing home a nice 4 1/2 for $30. You are right in mentioning that it is not easy as pie to flatten a board in this manner though, little learning curve there. --dave

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Silvan wrote:

Yeah, I have neither, and I'm saving for a (non-benchtop!) jointer.

I believe that, but it also might be just what I need to do in the interim.

Edge jointing, yes, I'm aware, but haven't tried yet. I have some 2s2 pieces that I will be going this route (pun!) on.

I know that! Boy, the 2s2 figured sweetgum/liquidambar I got at the small mom&pop mill was a better deal than the boring 4s4 yellow poplar from the BORG.

I think you meant, "the remaining face," but I got it.
Thanks, Chris
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Chris, some pieces of advice: 1) don't change your name. You know what your skills are and are willing to recognize that. That is a rare trait on this NG.
2) I've done lots of pieces before I ever got a jointer and, while I wouldn't go back to being without a jointer and I have done better pieces since I've gotten one, I am not convinced that a jointer is THE essential piece of equipment for woodworking. (I would suggest a list but then that would derail this thread).
3) You can safely rip a twisted piece on a TS if you mount the piece to a sled and shim the piece so it can't move. I've done this with an 8 foot, 16 inch wide, 8/4 piece of curly cherry that had a 2 inch twist in it. Frankly this is a PITA but worth it for the right piece of wood. A piece of Yellow Poplar, IMO, is NOT the right piece of wood. Replace it with a flat piece and use the piece you have for jigs and crap.
4) many wood supply places will not only plane your pieces but usually have a jointer too and will flatten the board as a service. Unless you have a quick project that you wanted to get done long before this thread ever ends I think a trip to a good wood supply store is worth it because you will be able to get the wood you want and also learn about your choices for future projects. This is something that will quickly move you from *_The New Guy_* to yet another wood dork (YAWD).
TWS
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TWS wrote:

snip

The problem with this "shim it on a sled" methods is that the resulting ripped edge IS NOT square to the face of the board, which in turn wasn't flat to begin with. Now if you want to edge join this piece to another that DOES HAVE a straight edge that IS square to it's face, or the edge you created is supposed to butt up against another part - like the bottom of a table top ... well, you see the problem. It's hard to make rectangles from trapezoidal parts.

Well, maybe. The problem is that wood, unless encased in plastic, WILL gain or lose moisture and therefore will change dimensions with changes in temperature and humidity. So, even if you had the stock milled when you buy it, if you don't make the parts you need for your project and assemble it "soon", it can bow, twist, cup ... Once the parts are assembled, the joinery will usually keep things were they're supposed to stay. But if you wait several weeks or months to use the wood your supplier milled for you, some of the previously flat, straight edge boards may not be flat and/or straight come assembly time.
And THAT's why it's nice to have a way, be it Neander or Normite, to make flat faces parallel to each other and straight square to the face edges - when you need them.
charlie b
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wrote:

You are right that you have edges that are not square to the surface but you still don't have a flat surface to reference to anyway. The reason for ripping to narrower boards is so you can reduce the twist to a reasonable amount that you can then trim to flat surface without losing too much board thickness. After flattening you would obviously need to do the usual edge treatment to square the edge to the flat surface and then do your glue ups to reconstruct a wider board.

from smaller trapezoids than from one large twisty. For a good example, see <http://tomstudwell.com/Projects/BarTop/photoalbum.htm

to make your own flat boards but I'm not going to discourage a NewGuy by telling him he can't make his bookshelf until he invests several thousands of dollars in his own equipment. The fact is he can get flat and square boards from a reputable wood supplier and he should pursue that and get experience and joy making something before he goes out and gets tools he doesn't need right away.
TWS
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