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I got some rough stock I ripped to about 1/2" x 2" . After jointing and planing I'd want to get to 1/4". I jointed one surface and got it nice and flat. I ran it through the planer and it came out bowed. I don't have much experience with jointing or planing yet. Is that common? Also I just changed the knives on the planer. Could I have screwed something up? It's a DW735. I also noticed the extension tables are exactly planar with the bed. They were only about 2 ft long so I figured that couldn't have affected it much.
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I reject your reality and substitute my own. -
did you plane all the material off of one side?Opportunity is missed by most people because it is dressed in overalls and looks like work. - Thomas Edison -
I jointed one surface flat and put jointed surface down on the planer. When I say surface I'm referring to the 2" portion and side as the 1/4".I reject your reality and substitute my own.Comment
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did you remove relatively equal amounts of material form the jointed side and the planed side during the processes. I haven't experienced it myself but I have always been told that if you remove more material from one side it will tend to bow.
on the other hand, wood has internal stresses, anytime you cut it you are releasing those stresses. it might just be part of the wood's structure. at least it is thin and you can bend it into place for assembly.Opportunity is missed by most people because it is dressed in overalls and looks like work. - Thomas EdisonComment
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I probably planed more material than I jointed.I reject your reality and substitute my own.Comment
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Thats probably the reason. The best technique (at least the one I use) is first to mark one face with pencil or chalk lines and joint until it is flat. Reference that jointed face on the bed of the planer and after making similar marks on the opposing face run it through the planer until it is flat. Then alternate faces through the planer until you get the thickness you desire.
If you are simply truing a board it usually wont be a problem but If you take off a lot more from one face than the other you will have a moisture imbalance and it could warp. I have had this happen.
Whenever you mill stock its advisable to mill it slightly oversize and then leave it to adjust to the shop conditions. Then check it again before use and mill it down to final dimension.Jon
Phoenix AZ - It's a dry heat
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We all make mistakes and I should know I've made enough of them
techzibits.comComment
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are you sure the planed board was flat and not bowed coming off the jointer?
Usually a planer is just a thickness planer and if the board is not flat to begin with it won't make it flat, just uniform thickness.
Maybe your jointer needs adjustment.
Loring in Katy, TX USA
If your only tool is a hammer, you tend to treat all problems as if they were nails.
BT3 FAQ - https://www.sawdustzone.org/forum/di...sked-questionsComment
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Well...at 1/4", I'm thinking it's a toss up. I've had a lot of problems going that think without it bowing out of shape due to the loss of the internal stresses that had the thing staying flat at 1/2".
Just my personal experience.Keith Z. Leonard
Go Steelers!Comment
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You didn't mention species.. if you took it straight from the joiner to the planer.. the moisture content and if it was flat sawn or quarter-sawn as I have no doubt you flattened one side before you planed it. All those will come into play IMO.
I re-saw often and it is not unusual for some species to come off the BS bowed if they have a lot of mositure exposed and they are re-sawn thin. You open up the stock to fresh wood where moisture has been trapped and if there is internal stress as the guys mentioned.. the stress release will show it's ugly head immediately.
I have seen some stock re-sawn from a flat 1/2" to 1/4" or under that was flat when planed or re-sawn.. but hours latter it would bow as it reacts to moisture release. Internal stress will show early.. fresh exposure to moisture or lack of... can take hours or a day depending on humidity and temperatures.
So.. I think what you have is normal and directly due to one of the above mentioned reasons it could bow. I ran 200 linear feet of Spanish cedar at 8% moisture content.. 11" wide for a friend that uses it for humidors for re-sell as he doesn't have a BS. This was sliced and diced from just over 1" into 1/8" veneers. No bow two weeks latter as Spanish Cedar is very stable.
I re-sawed some QSWO and no cup to speak of at 3/16". But.. flat sawn red oak.. white oak.. pine.. maple are more likely to bow when flat sawn. Just the way it is IMO and you learn to deal with it. I may suggest turning the bow side up and let it acclimate a day or so. The bow may come out.. it may partially come out.. or you may have to just deal with it.
Good luck...Last edited by Guest; 03-01-2009, 10:52 AM.Comment
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Loring in Katy, TX USA
If your only tool is a hammer, you tend to treat all problems as if they were nails.
BT3 FAQ - https://www.sawdustzone.org/forum/di...sked-questionsComment
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That is what is causing your problems. It needs to be air dried. It is the difference in moisture that is causing it. When it gets stored outside, untarped, the moisture gets into the board pretty deep. Then it only dries on the outside and the inside retains a lot of moisture."A fine beer may be judged with just one sip, but it is better to be thoroughly sure"Comment
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I have it in a dry location now but the person I got it from left it in the open. I'm not sure how long he had it that way. What am I looking at time wise to get it reasonably dry. If I have time today I may pick up of those moisture meters from Rockler. What % should I shoot for?I reject your reality and substitute my own.Comment
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6-10% is about right for most wood working. If you got one of the 20$ ones, they only read down to 10%, so if you don't get a reading, then you are probably ok. If it reads above 10%, I'd like it dry some more.Keith Z. Leonard
Go Steelers!Comment
you didn't mention that either.
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