How Would You Saw These?

[jeepcj779]

I cut a SYP down a couple weeks ago. I finally got it moved where I want it and I'm going to start on it tomorrow. It was a field edge tree, so the branches started pretty low down. I was able to get two good 12' logs, one OK 12' log, and two 10' "pieces of tree". I plan to use them for B+B siding:

 


 I ask how you would saw these because I'm not sure how to handle the off center pith in the butt log when making boards for siding.
  I also have these "tree pieces". Would you even bother with them?:


 

[moodnacreek]

I saw stuff like that all the time but I will not buy it with the knots sticking out like that. I would spend almost as much running the chainsaw as the sawmill.

[Den-Den]

My drying stack foundations are cement blocks with short 4" x 6" timber cross-ways.

Those "pieces of tree" would be used to make 4" x 6" x 4 ft if they were near the mill.  If they had to be transported, I would likely leave them behind.

[WDH]

I would saw the big butt log with the off center pith such that the rings were balanced in each board.  Essentially, you saw the log to form a cant that has the pith as centered in it as best as you can get it.  You basically saw around the log to form the square cant trying to form a cant that has the pith centered.  You probably cannot get it centered on both ends the same, but you just have to do the best that you can do.  In doing this, when you saw the final cant with the "centered" pith, you want to saw that cant where the "hump" of the log is either the face down on the bed or the top of the cant.  In the big SYP mills that my Company operated, we described logs with sweep as having "horns".  You saw the final cant with the "horns" up or the "horns" down. 

[jeepcj779]

  moodnacreek, I am fortunate enough to be both seller and buyer of these here logs...any chainsawing will be done by me, either before or after the sale. 
  Den-Den, I may just make said 4x6's from those horn logs.
WDH, I will center the pith as you recommend. There will be a fair amount of waste. What should I do with it?
  I thought @Southside would have commented by now. He was admiring my logs last week...he is probably still working.

[Magicman]

Follow WDH and you will do fine.  Another way to describe the setup is to lay the log on the sawmill with the off center heart closest to either 3 or 9 o'clock.  Establish your targeted cant and notice that the pith will be centered within that targeted cant.  Saw down to that targeted cant on your 1st and 3rd face opening.  Turning 90° after each face opening your final saw through will be from either the hump or horn face.  The cathedral pattern will be centered within your boards and they will tend to bow but not crook.

I do not see why there would be any waste.  ??

[jeepcj779]

If I center the pith in both directions, which is what I thought WDH said to do, then a good part of the bottom of the butt would be "wedged" off the centered pith.

[Southside]

he is probably still working.

Yup - just sitting down to supper now.  Like WDH said, sometimes you do what you can.  Think ahead to what it is you are trying to produce, and what defects are easier to live with.  In this case, B+B, it's far easier to live with bow than crook.  Since the pith will be off set, or even run out on one end, plan for the stress to pull the boards to the face since you can nail them flat later.  If you build in side sweep or crook then it will be a lot harder to keep your siding straight on the building.  

If the stress is strong enough you will see the lumber moving on the cant as the sawhead travels down the mill.  Keep in mind you may also see the cant move from the same stress being released and may have to adjust the plan accordingly.  

As far as waste goes - good, clean, grain, turn it into stickers.  You are going to need a mountain of them anyway.  

From your tree pieces I often recover a fair bit of "random length, random width" material that I sell at a discount.  Go after the post or dunnage that you need and turn the rest into a bargain for someone.  It all sells eventually, chicken coops, garage sheeting, who knows, but folks come and get it by the stack.  

[Magicman]

The only difference between this illustration and your question is that when the 3rd face (4th picture) is opened the targeted cant is not split.  I still fail to see the waste that you question.  I regularly saw off centered pith SYP logs on every job.  Well not only SYP logs, but every species.  I sawed some off centered pith Oak logs today and will saw some off centered pith SYP logs tomorrow.  How do I know about tomorrow?  Because there are very few perfect logs and every whack of logs contains some with off centered piths.

LINK

[jeepcj779]

  Magicman, I guess the waste comes from not being off centered the same at both ends. The larger butt end has the most offset, so if I center the pith at both ends, there will be a larger amount of wedge to remove on the butt end, and some on the other end to get the pith centered. I picture it like cant is going diagonally through the log.
  I remember seeing the post from the link you provided. That is likely how I will saw it, except 1x12 instead of 2x6.

[Magicman]

You are being overly concerned about the pith being off centered on the top end.  Remember that you are sawing lumber for siding.  

[jeepcj779]

My 500 bdft or so of experience so far is not enough for me to know better. I'll remember its barn siding and try to be less concerned tomorrow when I'm sawing it up.

[customsawyer]

Keep in mind that what caused that off center pith is that the tree was growing on the edge of a field. It will have stress in it. The reason it only had limbs on one side is because the other side self pruned as it was growing. This tree spent its life growing away from the other trees towards the sunlight. That lumber is going to move and the cant will react.

[Magicman]

Avoid saying "always" and "never". Sawing a log depends upon the cut list and the setup/sawing can be much different.

WDH's cut list is generally sawing premium grade lumber for the higher end market.  His setup can be much different to realize that particular yield so yes he may very well be particular to center the pith on both ends of the log.

Your cut list is sawing B&B siding and you want the highest yield from the log while still producing a suitable product.


 
Your cut list is what I addressed with the above picture.  Center the pith top to bottom by turning the log as shown.  Measure the distance from the pith to the sawmill bed rail.  Now use your toe board, etc. and raise the log's top end so that the center of the log (not pith) is that distance from a sawmill bed rail.  Do not be concerned where the pith is on the top end.

I used this log's butt end as an illustration, but my target was outlined on the log's top end.  A log will only yield what the smaller top end will saw.

[alan gage]

I sawed up a bunch of board and batten siding for my house and shop from little spruce logs. I tried to do like others here have suggested both in terms of how to saw the log and to realize it's only siding and not be super concerned with it.

Nice thing with board and batten is that if you have boards with sweep it's not so important because the batten will cover the gaps between boards. And if you end up with a wandering pith ruining several boards you just rip them into narrower battens.

Alan

[jeepcj779]

I didn't get pictures of the really off-center log, but here is the one I did today:
One:



Two:
 


Three:
 


Four:


 
Wide:
 

 
Heavy:


 

Once it was squared up, the cant was a little more than 10x20 inches, 12.5 feet long. Those 20+ inch wide boards were a pain to edge. Two-man lift, only one man available. Thanks for all the advice.

[Southside]

Nothing wrong with that at all.  You getting batten from edging the 20" pieces?

[jeepcj779]

Anywhere I could not get a full board, I made battens or stickers. Everything else went to the scrap pile. I also made a few mistakes in case I needed some extra scrap.

[WDH]

Well done.  Rings nicely balanced!

[btulloh]

I also made a few mistakes in case I needed some extra scrap.

:D  

Always a good idea.  Scrap can be hard to come by around a sawmill and you certainly don't want to run out.

[alan gage]

:D  

Always a good idea.  Scrap can be hard to come by around a sawmill and you certainly don't want to run out.

Haha. Sometimes I shake my head at the stuff I cut into pieces for the wood stove. Yeah, it might come in handy someday but it hasn't found a use in the last 6 months and I'm tired of it being in my way in the shop. And it's not like there isn't plenty more where that came from.
Alan

[WDH]

Had a customer today find some 4/4 pine cut-offs about 10" wide and 18" long in the edger strips scrap pile, about 3 or 4 cut-offs.  He asked me why they were there as they were good wood.  I told him that at some point you have to draw a line.  With probably 50,000 bf of lumber, those scraps are nothing but time-wasted-trouble to fool with  . 

I told him he could have them and any others he could find and he was happy.