Quarter Sawing with the WPF

[Qweaver]

I have an Oak log that will be over 40" on the small end. Can someone show me a drawing of how to quarter saw this with a 10" WPF.  I guess excluding the sapwood will be the real problem.  I've looked at the pattern on the Peterson web site but it does not give any directions.

[Nomad]

     As far as this goes, Lucas or Peterson doesn't matter.  I think that, without getting stupid about it, the easiest way is to saw the top third of the log vertically, the middle third horizontally, and the bottom third vertically again.  If you measure it out on the log you can make cuts to edge off the sapwood from each board before the board is actually cut from the log, if so desired.  (I've seen diagrams that explain it better than I just did, but can't find one right now. : )

[terrifictimbersllc]

The Peterson diagram titled "Quarter (Grade) Sawing) is how one can do it, it just doesn't show what to do with the upper left and upper right rift sawn material.  Are you wondering whether to take those out as vertical vs. horizontal boards?   Regardless the first cut is horizontal across the top, sawing off the top of the vertical QS boards to eliminate the bark and some of the sapwood if desired.

Depending on the thickness of the QS boards desired, I'd sure consider cutting out up to 10x10 cants and resawing it all on the bandsaw, if I were set up at home with a bandsaw and machine there!  One can process the corner cants into pure QS material on a bandsaw pretty easy too, if the rift sawn material isn't sought.

[Ianab]

What the diagram on the Peterson page doesn't show is that you edge the bark / sapwood off as you go.

So the first step is to flatten the top of the log until you are in to the good stuff. Now you have a "corner" section of this first "layer" that's going to be rift sawn. Just recover what you can from that area. Now the 12 O'Clock section of the log has been edged on the top, take your good Q-sawn boards from there. As you get across to the other side, there is another corner of rift sawn to deal with.

Now with that size log, you wont actually be 1/3 of the way though, so you need decide what you are going to do next.... You should be around the 10 O'C area now. I would suggest switching to horizontal boards, and taking some of those, doing a vertical adjust for each board. Once you are down ~6 more inches, then you have another row of narrower vertical boards in the 12 O'clock area, and horizontal again on the other side of the log.

Now switch to horizontal, and take 2 boards from either side of the pith. The centre of the log is low grade, knotty and unstable, probably firewood. As you open it up you will see where the knots and defects begin, and you can adjust your board width to suit. As you get past 1/2 way, reverse the procedure for the bottom section of the log. The last bit of sapwood is left laying on the log bunks.

But all the boards can be taken off the mill fully edged, even if that means another pass with the mill, it's only a 1 or 2" cut and you breeze though it in seconds.

Cut your 10" boards from the outside of the log, as that will be the best quality. If you get into lower grade material with a 5 or 7" board it's not so bad.

Another idea might be to actually start sketching some pattern on the end of the log, See what you can make fit for the best recovery.

Remember you don't actually HAVE to stick to any fixed pattern. You can adjust your cutting on the fly when you see what's inside the log. If you find knots, it may be better to switch to taking some flat sawn which is more use in the lower grade wood.

Hmm. hope that makes it clearer. It's not actually "hard" once you see it happening, but it's a different approach to how you would do it with a band mill.

Ian

[schmism]

 

Do the two ways shown ACTUALLY produce the same quarter sawn material?

[dgdrls]

Quarter (Grade) Sawing  From the Peterson web site.

Quarter sawn boards are cut from the log where the growth rings run parallel to the narrow sides of the board. This style of cutting is considered to be the most ideal cut, and is more attractive than flat sawn lumber. Some species of trees such as oak reveal beautiful ray flecks when quarter sawn, and these boards are prized among furniture craftsman. Quarter sawn boards are much easier to match the grain when boards are laminated together.

For many sawmills, producing quarter sawn boards takes longer to cut, produces less board footage (cubage) and creates more waste. The flexibility of a Peterson Portable Sawmill makes cutting quarter sawn lumber an easy task with minimal effect to production figures, speed of cut and waste. The unique design of the Peterson Portable Sawmill allows you to cut quarter sawn boards directly from the log with no additional log or board handling.

Quarter sawn lumber produces a beautiful grain,which is ideal for use in areas on display such as cabinets and doors etc. Quarter sawn boards behave in the opposite manner to flat sawn lumber. They have a lot less flex because the grain runs perpendicular to the face of the board. Quarter sawn boards are quite stable and very strong, and are therefore ideal for use in weight-bearing applications.

When cutting quarter sawn lumber from high tensioned logs the grain will cause the board to bow like a banana. As quarter sawn boards are very strong, bending these boards straight is almost impossible, and for this reason we recommend flat sawing high tension logs.

 

hope this helps.

DGD

[Qweaver]

I've drawn a scale view of how I think I should cut this log and I'm going to try it out on a 40" poplar that I have.  I'll see how it goes.

[scsmith42]

Quinton, below is a drawing showing how I typically QS with my Peterson.  There are two important things to do when you're setting up the log.  First, be sure that the center of the pith is the same distance from one rail on each end of the log.  This will ensure that your vertical cuts are parallel to the pith.  Second, level the pith relative to the tracks, so that your horizontal cuts are parallel to the pith.  I always level my log parallel to the tracks first, and then adjust it as needed from side to side in order to line the pith up in both planes.

These two steps make a big difference in the quality of the QS from end to end on the board.

For a 40" oak log, I'm usually going to leave at least a 4 x 4 if not a 6 x 6 in the middle, so that my QS boards don't have any juvenile wood in them.  You will also lose a 2 - 3 inches on each side of the log for bark and sapwood.  Thus, a 40" log will usually produce boards up to 14" wide (where you can double cut them). 

When you start milling down from the top, if you make your first layer of vertical cuts 4" deep, then your second layer will produce 10" deep QS boards - all technically QS (45 - 90 degree ring orientation).  About 1/2 of them will be rift, and the others closer to a pure QS.

Assuming that I'm milling a 40" log and want to max out my production of wide boards, after taking the 4" vertical cuts across the top of the log, I may do some 4" horizontal cuts along the left edge of the log, until I get to a depth of 10" down from the top. Then I'll swing my blade vertical and make 10" cuts across the top edge of the log.

This diagram "tries" to explain what I'm saying.  Note that I'll change up my milling pattern based upon the growth ring orientation in the log.

Scott



 

[sigidi]

I've drawn a scale view of how I think I should cut this log and I'm going to try it out on a 40" poplar that I have.  I'll see how it goes.

Mate, it seems you've had some pretty darn good advice - always hard putting actions into words, but the guys seem to have done pretty good...like you said, give it a bit of a go on your other log and I'm sure you'll have it all sorted before you get half way through, but at least you've kept your good log and made any mistakes on that poplar  ;)

Let us know how ya go mate

[Qweaver]

OK, I think I've got a handle on this.  Thanks for the input everyone.  I've quarter sawn some smaller logs in the past but this 4' dia. log is a whole new game.  I think it will make some great lumber.
Quinton

[dgdrls]

Qweaver,

any Chance you could post some pics as you go?
Would be nice to see the steps you take.

good luck with that log
DGDrls

[Qweaver]

I'll post a pic of my drawing and then see how close I can stick to the plan.   Best laid plans, etc., etc.

[sigidi]

good stuff mate  ;)  8)

[Qweaver]

I'm sawing a 32" poplar just the way that Scott drew it and it is working great.  There will be some rift but even that should look good.  I ran out of gas about 80% thru the log and will finish it in the AM.  It is more time consuming to saw this way but some of that is "thinking" time.
There is not much reason to quarter saw poplar but it is sure looking good.  I'll post a diagram of exactly how I did it when done.   I'm cutting mainly 8" boards because it fits well on this 32".  I can do the full 8" single pass cut on the poplar.  I don't know if I can do that on the red oak at 10".

[Ianab]

The horizontal ones will probably run easier if you do it in 2 passes. Vertical should be OK, just a bit slower.

Might be a good chance to try some double cutting as well? You only get one double cut per layer, but if you see a nice 16" wide Q Sawn board sitting there in the log, it would be a shame not to cut it out right?

Bit more brain work, and it does slow you down, but for those special boards it's worth the effort.

Ian

[sigidi]

Can't wait to see the fruits of your labor ;) ;)

[Qweaver]

Here is a diagram of how I sawed the 30" poplar.  Note that I cut boards all the way thru the center.  Not the best way I know but the only way I could easily do it and the boards still came out looking good.  Poplar is not the best wood for quarter sawing but it made excellent looking lumber.  It was a great log. Less that 2" taper in a 9' log and very few knots.  I got mainly 7.5 to 9" boards.  Some rift but mainly QS. I was offsetting the saw 1.25" each cut and the boards were slightly over  1".  I continued sawing the bottom in the same pattern.
I really liked the look of the finished boards.  The large oak that I have to saw will be over 40" on the small end and I will saw it the same way and try for 10" boards



 

[Qweaver]

I liked the look of the lumber so much that I may make this my normal way of sawing on the swinger.  It may have taken a little longer but worth the extra time especially for Oak and Sycamore.  And very little lost lumber over flat type sawing.

[Nomad]

     Qweaver, I'm gonna hang onto that diagram.  Next time I fire up that saw I may just try that. ;D

[Ianab]

Yeah, that's a good diagram.  Exactly what you do with the "corners" and the middle of the log can vary depending on what you need. Sawing 2x2 or 3x3 out of the corners can work as the rift sawn squares like that are good for table legs etc.

Remember you can combine the two methods as well. When you get nearer the pith you often get into knottier wood, and that's no good quarter sawn. The knots go right across the board and make it basically useless. But if the same wood is flat sawn, you still get a useful board, all be it with some knots in the face.

The 3 O'clock section of the log is also where you can try out some double cutting if you want some even wider q-sawn boards that the wood workers go nuts for. So look at the vertical step as you saw out the pith area. You will see when you get into clear wood again, and then decide what to do. If you have 16" of wood left, then set up a double cut and get some of those sweet boards. Takes a little more time, but if you can sell the wood for a premium (or just like boards like that  ;) )it worth the effort.

Ian