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White oak crossgrain and better cutting.1/3
I have a good sized stack of white oak 600bf lumber and when I planed it, I really struggled with planer tear out. I am running an older foley-belsaw 5hp planer on 220v at its lower feed rate. I replaced the knives, but the tearout continued. When we followed with some walnut for a test, the quartersawn walnut planed perfectly. Now, the white oak trees or bur oaks? around here have lots of lower branches that spider off the tree and I'm guessing those spider branches are the source of the crossgraining, but the white oak was cut by a different sawyer that did not quarter much (sadly). The good news is most all the lumber planed down to 0.875", so I have some room to pick a good side to clean up. Question is, do I have to run these all through a sander instead of planing? On the same subject, but a little different, should a sawyer be lining up the pith in white oak and cutting the pith into something like a 4x4? Most of the pith wood really was impossible to finish nicely and even though air dried slowly under a cover still cracked up. Is some of this on the sawyer? I paid a sawyer and was a little frustrated that he didn't quartersaw more and level the logs to cut out the pith. Is it just me or is it a little criminal to flatsaw white oak? Some of the boards were 14" wide, and I ended up throwing the whole board out because it simply would not have made much. It is long past the time I would talk to the sawyer, but he was in a hurry to get in and out in a day and I got a lot of not very nice lumber as a result. How do you avoid a bad contract sawyer? His rate was 75/hr. and I never asked him to hurry at all. How can you avoid this with a sawyer and how should large white oak logs be sawn in general and any advice for the cranky/grainy flatsawn lumber I have? (and I realize some of flatsawn lumber is rift and quartered, etc) This is meant to be educational and for me to verify my suspicion/attitude that this wood was not cut very well.
Tearout is caused by several factors, oftentimes two factors tHat individually not an issue but together they are a problem...2+2 = 8.
Low MC (under 6.5% MC), knife angle is too slender, rake angle is too large (determined by the head), knives not all in the same cutting circle, too much land (too much jointing), knives not sharp, feed too fast and removal rate (depth of cut) too large, too much swirly grain, wood not held firmly.
MC was 13%, knife changes yielded no difference, graining was very swirly... I think it is just one of those times when the wood didn't cooperate. The feed rate slower might have reduced the tearout, but I was going as slow as the machine would go..
Let me talk to the sawyer part....
Lumber should be sawn for how it's going to be used. If your sawyer didn't ask you what you plan to do with the lumber, or what you want out of the logs he's sawing, you should have told him. If he told you something else, or that he couldn't do it, then that's the time to call someone else.
White oak makes great trailer decking, fence rails, barn flooring, and other outdoor use lumber. In those situations it is often flat sawn. And while white oak makes excellent quarter-sawn lumber too, it takes a lot of effort and skill to quarter saw, and not all sawyers are up to it. And not all customers are willing to pay for it. Quartering also reduces the overall yield of a log so you end up with less usable lumber.
If you didn't communicate with the sawyer what you wanted, then there is no reason to blame him. Quarter sawing takes at least half again as much time as flat sawing, and has no advantage for many applications. The sawyer was probably just trying to give you the best value for your money. Another thing that might help is ripping the wider boards before planing, then edge gluing them back together. This is a common practice that helps relieve stress, as well as giving better yield if the boards are cupped. I agree about the spiral head idea.
So, defending the sawyer.
Is it a good practice to run heartwood in multiple boards, or a better practice to dog the log and cut to remove the pith?
When I asked the sawyer about dogging the logs to get the pith in one board, he said he'd have to work an extra day and he was only going to be there for one day. Probably should have fired him right then eh?
Is it a good practice to cut 14" wide boards? I threw all boards of that log but 3 away as they were too cupped and rounded and facebowed to do anything with. Then my yield from the 3 boards was literally about 6 bf.
My original question was somewhat about whether quartersawing would have resulted in less crossgraining and tearout.
The spiralhead was probably the best answer.
Slope of grain was precisely what I was wondering about; didn't know the reference. Thanks! Where can I find out more about it? Every board I have would have it, save the walnut cut by another sawyer.
Slope of grain is more for strength in construction grades (conifers), not appearance grades (mostly hardwoods and some soft wood).
SOG (slope of grain) does apply to the top grades of hardwoods in that end spilts cannot deviate more than 1:12. This applies to FAS, FAS 1-Face, and Select grades.
Indirectly, it applies to all grades in that SOG can cause warp and warp is a serious defect.
When one planes "against the grain" then chipped grain is more likely, but if planing one piece of lumber with the grain, the other side will be against the grain unless the lumber is turned end for end...not possible in medium and larger operation. So, we use chip breakers in -layers that are adjust precisely so that chipped grain can be avoided.
As stated earlier, the MC and drying temperature are likely the biggest factors affecting the development of chipped grain.
The MC of the 3 year air dried Minnesota in November batch was 12-14%. We had nearly zero checking, except near pith.
It would have been really hard to run each board with an sog reference, but I suppose I could have blackmarked each end for grain direction off center. I marked defects on the face with a crayon and check mark the board if none. It would be a lot of looking, flipping, spinning, and I like to run end to end...
At this point, I'm crediting swirly grain, planer speed (running slowest but still plenty fast), knive angles, knife type, and slope of grain a bit, kind of in that order. I hogged very lightly to the point my offbearer was getting a little mad at me. That caused the most frustration because a 0.030 hog still was tearing.
Thanks to everyone for responding. I learned plenty and am grateful.