Tulip Poplar, need the Pro's advice.

[homesteader1972]

Hello All,

On my last job, I cut a lot of Tulip Poplar into 2X framing material. It was sometimes difficult to cut it where I could keep the heart (green center) all to itself and not get some boards with some crook. Most of it turned out well, the customer was very pleased.

My next job will also have some Tulip Poplar for 2x4 and 2x6, and was wondering how you guys approach sawing poplar into 2X's. On small logs where they will come closer to squaring six inches its no problem. But on larger logs where there is a large heart it poses more trouble. What I did last time was cut 2X's from the sides until the desired cant width is reached,keeping the heart centered, but made for a lot of edging, but worked well enough.

Also, how thick does poplar need to be milled if used for siding so it will not cup.

Any input would be appreciated.

[Magicman]

I am reluctant to reply 'cause I ain't a "Pro", but here goes my take anyway. 

Poplar is not a "go to" species for framing lumber but it is sometimes all that is available to customers so you saw what's there.  I do not believe that you can completely avoid the warp/crook/bow reaction of some of the lumber that you saw regardless of how your orient the log or cant for sawing.  Note that you will also sometimes get some adverse reaction when sawing a perfect Pine log.  Always sawing through from the hump or horn side will minimize this loss.

The thickness of lumber has little to do with cupping.  I have sawed/installed ¾" & 1" with little or no difference.  How you orient the board does make a difference.  Lumber cups toward the bark side which is away from the pith side, therefore always install it so that the boards cup inward toward the studs.

[Magicman]

Never ever split the pith when sawing framing lumber from any species.


 
Sawing 2X4's


 
Sawing 2X6's.  If you can not get three cants then bring it down on each side to one cant and edge the side lumber into 4's or 6's.  Never split the pith and saw two cants.

[bkaimwood]

Well said MM, great advice...the only thing I could add would be, of coarse, to keep flipping the cant as stress is noted, to relieve it, but on many species, on many jobs, finding yourself flipping the cant every board or two ends up being counterproductive... You spend more time than the end product is worth...all depends on watcha sawin'?!! :)

[Kingmt]

I hate to hijack but what do you look for that indicates stress?

[slider]

Fairly simple.When you are making a cut and you see the board lifting from either end or the middle you have stress.

[customsawyer]

Placement of the pith is one of the first clues. The second would be how much end checking and how deep the end checking is. If the log has deep end checking then you can brace yourself.
When it comes time to cut the lumber you can keep flipping the cant or you can do as MM does and leave the other lumber on top of the cants. The other lumber will hold it down where it don't move as much.  ;)

[Kingmt]

To keep from hijacking this thread anymore can you point me to somewhere to read more about this? I understand leaving it in the middle but but the turning the cant still leaves me wondering. If the board moves in any way to you just flip & start cutting somewhere else or how do you come up with a plan?

When I ordered a sawmill I just thought you laid it on the mill & started cutting. I'm finding out there is way more to this then I ever expected.

[customsawyer]

First you need to understand that none of us know it all. One of the things I love about cutting would is that every day I get to learn.
If the pith of a log is off from center than there will be some stress. When you center the pith of a log try to center the pith of the whole length of the log not just on the end that you can see. If the end checking is wide and deep there is going to be stress on all sides of the log. The end checking is the log drying a little and trying to rip itself apart. As you are sawing watch how the board or slab you are cutting moves and it will let you know where your next cut needs to be to relieve the stress.

[Kingmt]

Seems like knowing it all would be so boring with nothing new to learn. I'm just a little overwhelmed in all of this ATM. As always in learning something new or even learning more about things your quite good at the more you learn the more you find out that you don't know.

What I'm not getting is which way to turn the board in relation to how the board moves.. In everything I've sawed so far I've not noticed anything move. Seems they just lay down of the cant behind the blade. Altho I didn't know to look for it.

[WDH]

Smaller yellow Poplar logs are notorious for stress. 

[Ron Wenrich]

Tulip poplar also gets spiral grain.  You'll be able to see it if you look at the bark pattern.  It will twist around the log instead of being straight.  Lots of stress in those logs and the lumber is more prone to twisting.  Other species also have this problem.

[customsawyer]

Look for end checking like this.


 

When you see it duck, as the board might meet you at the other end of the mill.

[Kingmt]

Am I right in guessing you'd probably cut with the crack so the board would be more likely to warp instead of bow?

[beenthere]

King
Bow is warp... and you may have meant crook.

[Kingmt]

I've always heard bow as on the narrow side of the board & warp on the wide side. I actually usually call it crown tho. I'm only going on about an 4 hours sleep since Monday morning tho so my brain isn't working quite right ATM. Crooked has always been used to describe any bent any way but usually retained for junk boards that goes every way. Lol

Around here if we say "That board is crooked!" It means it is only good for fire wood. If you've been to the local Lowes or Home Depot & looked at the framing lumber about 90% of it falls into that category.
Last time I went to the local lumber yard all I wanted was 20 framing grade 2x4x8' That I paid for in advance but after going to get them I had to go get my money back because they didn't have a board to use that was good for anything other then the fire pit.

Sorry enough side tracking & story telling.

[beenthere]

Hope this helps.

crook is a form of warp.. and not the same as "crooked".

Crook is edgewise deviation along the length, and bow is flatwise deviation along the length.

twist is also a form of warp.

Cup is deviation across the width of a board. 

Does help to try to keep them straight when discussing warp, as different sawing patterns can have their effect on the results.

[Magicman]

Jake, what are those strange marks on the right end of your toe board roller??   ???

[Kingmt]

Yelp. Need a guide on some of the letters & I'll be good. ;) I figured out CSM pretty easy.

[customsawyer]

Jake, what are those strange marks on the right end of your toe board roller??   ???

It is but it isn't what you think.  ;) That toe board roller is one that I welded on to the movable table that came on the mill. It sticks up a bit higher than the bed rails and I have removed my brake from the mill. I had told one of the hired men to fill the diesel fuel tank and he lowered the mill in the wrong place. It did sound bad if that tells you anything.  :D

Am I right in guessing you'd probably cut with the crack so the board would be more likely to warp instead of bow?

When sawing for grade I keep the cracks at a 45° angle of the blade. This allows me to edge off the cracks in the lumber and improve the grade. ;) When you get to where the crack is costing you lumber you turn the log and cut the next face.

[homesteader1972]

Hello All,

Thanks for all the great information, you guys are great! All the poplar so far is looking really great and the customer is very pleased.

Thanks again!

[TnAndy]

Smaller yellow Poplar logs are notorious for stress.

Amen said the choir !

I've gotten up on the cant and walked on it behind the saw head trying to keep them down on the bed   ;D