WM claim "Special two-plane clamping system simplifies sawing of stressed logs"

[RIMwood]

I pulled this quote from the Woodmizer web site "Special two-plane clamping system simplifies sawing of stressed logs".

I'm new to the forum, not sure why I have not joined years ago, so much incredible information!
I have a 2002 LT40 manual mill, and I have been thinking of converting my manual to a hydraulic mill. There are great posts on doing the conversion. I really like  pineywoods conversion for the log turner and clamp, such a clever and simple design. Then I saw the WM claim on sawing stressed logs and now I'm thinking the 2 plan clamp might be worth the effort, not sure my skill level is up to it, you have to cut the frame to install it like WoodenHead and others have done.

I have a lot of Ash blow down from hurricane Sandy in 2012 that I have not yet milled. It milled fine back then, but now, not so much. I guess the logs are developing stress from drying over the years. Seems like the ability to apply downward pressure to a cant and hold it while on the mill might actually help to get a straighter cut.

So, my question is to WM sawyers with 2 plane clamps, does the 2 plane clamp actually help sawing stressed logs?

[pineywoods]

Rimwood, I did some serious looking at adding the factory hydraulic parts to my manual lt40. There are a couple of guys on here who have done that, but be aware there are some not-so obvious gottcha's. Even if you are good enough a welder to successfully modify the frame, the parts don't just bolt on, welding is required in other places. Real easy to mess up a good mill. That frame is constructed using a heavy steel jig to hold everything in place during welding. Next, the electrical system is nowhere near robust enough to support hydraulics. The pump motor will pull upwards of 200 amps. As to the 2 plane clamp, I admire the design, but it does have limitations. It's not designed to apply a lot of downward pressure, mostly sideways against the backstops. In the hands of an experienced sawyer, it can be used for a lot of other useful tricks besides just clamping...

[terrifictimbersllc]

I don't actually know what they mean by that.  But guessing that it means that the clamp can hold the cant tightly to the bed. To prevent the center from lifting.  It won't prevent the ends from doing so.  I'd say generally when I'm down to 4-5" on the cant then I clamp tight and go for it.  The larger the cant or the more the stress, it can pop loose and then you could lose a board if you're sawing that way.

[RIMwood]

Thanks for your input pineywoods. I can probably handle the welding but like you said "Real easy to mess up a good mill", which is why I really like your design. Not worried about the electrical system, plane on hooking up to my tractor hydraulics or maybe a log splitter I'm not using.

[RIMwood]

 terrifictimbersllc, I'm not sure what they meant either, good point about the ends, although it seems they bow up in the middle most of the time. I'll try clamping it and see how that works. Not use to these stressed logs, most of what I have cut in the past lays nice and flat on the mill. Do you run across this problem a lot?

[terrifictimbersllc]

Generally the cant will bow up in the middle as one is taking boards off the top,  as one goes towards the pith.  Cant now has a concave face pointing down (lifted up in the center).  On flipping it, the ends are up now, as boards are taken off, the ends go down to the bed. Right after it is flipped, if the cant can be held to the bed in the middle by very firm clamping, it can be finished off into mostly uniform thickness boards.

[barbender]

You would have to have spiked backstops, and some kind of spike on the clamp to bite into the cant to hold it down. I think Cook's mills have something along those lines. I usually just keep flipping the cant as I'm sawing, no big deal when you have hydraulics. Maybe that's what WM meant by that statement? You can flip a cant quick with that 2 plane. If you're having to flip the cant after every 3rd cut on a manual mill it would be a pain.

[Magicman]

I find that it is much better to flip the cant and prevent the bowing than to deal with a cant that has bowed.

[terrifictimbersllc]

Ease of flipping is a better example of how the clamp helps in sawing stressed lumber than the one I gave.  Nevrertheless the clamp on my LT40 has ridges in the side to give some bite, and what it clamps against directly opposite the clamp, also has a ridge.  The two together can indeed hold a the cant tight to the bed, within reason.  For example if I have 4 1" boards left to go, to finish off, I am usually going to clamp the cant tight to make the last 3 cuts rather than consider flipping it again. 

[Chuck White]

Not to sidetrack this topic, but I have a question!

My friend bought a new LT35HD last year and while giving him a hand with it one day, I noticed that when he was edging some flitches, that the 2-plane clamp can't clamp a one inch board!  It will only close to about 1½ inches!

Is that normal?

If so, wonder what the idea was behind it!   

[terrifictimbersllc]

Do you mean the clamp doesn't go in far enough to clamp a 1" board standing vertically?  For example if you were wanting to edge a 1" board.  Or are you talking about a 1" board lying flat on the bed?

My mill needs three 1" boards standing on edge to clamp tight, unless I swivel the head by hand or use another board lying on the bed.  It's because the cylinder when closed leaves the clamp open about 2-3/4".

[Dave Shepard]

That's normal on my LT40. I just toss a 3x4 piece of dunnage on the deck.

[scully]

On stressed logs there is not much that can be done bye clamping in my opinion . At least not on a LT40 hd . I've trieed to suck down cants for the last 2 or 3 cuts and seldom have success . If a log moves on me allot I sometimes re-flatten the face before the next board cut . I don't feel that the clamp offers a big advantage other than hold .

[Peter Drouin]

I can pull in down if I have to.
 

  

 
Fangs, 

[Magicman]

Yes, I quite often grab a board to use as a supporting spacer when I have less than three 1" flitches, but my "stick" is always there when needed.
 

 
My present White Oak stick replaced the broken Cherry stick several years ago.  It's painted stripes distinguishes it as a tool.  It sees service both in the horizontal and vertical position.

[4x4American]

Fast forward to 40 seconds in to this video, we need these cant hold down clamps in america.  The bi plane clamp is great but it does little to eliminate stress you have to saw in a manner to level the stress out.  Then go to 2:25 and see the powered rollers, another thing we need in America!

[paul case]

I cant edge 1 1'' board on my 94 model lt 40 or on the 2013 lt 40 super.

I think the clamp on the '13 is awesome  but it may not straighten a bowed cant.

We  have been sawing some 10''x10'' timbers and sawing 3'' thick side lumber. We can place the 3'' flitches on the loader arms and with the 2 plane clamp Scott can move over and stand those heavy boogers up and edge them without touching them by hand most of the time. That thing is awesome!

PC

[WV Sawmiller]

Chuck,

   Even 2" is a bit thin to clamp tightly on my LT35. I mentioned this at a seminar to Marty Parsons who was there and he showed me the trick of putting a 1" flitch on the mill to be edged then laying a finished 1X4 or 1X6 down as a spacer. Before I had stood my spacers up beside the flitch to exceed a 2" width but the ends before and after the clamp still tended to shake badly at times. Laying it down flat like that put more pressure on the whole length of the flitch to make it more stable to edge and I assume that is what Lynn is doing with his Magic stick he shows above.

[drobertson]

as far as handling stress in logs, well, some just don't and won't behave, they are bad boys,, I had to take a cut off the bark side, then 90° clamp and another cut off the bark side,, then flip to the third side, bark only working towards maybe a 4" face, a little more maybe,, watching how it's laying on the bed of course, then the fourth, thin slab cut again.  Some logs that I knew may be bad, I flipped a few times, just to let the know I had the horns you see, ( my Festus) poor at that impression, but all kidding aside, logs are or can be really good and really bad, and bout everything in between.  The clamp will help on many logs, if you know what to do and what to look for.  It does take time,,and a few long bows,,   Just saying.  Bad logs with off centered piths, well I'm sure I can have a chorus of support on sawing these horn toads,, it's a match and a pile of the best of whatever you can make of them

[Magicman]

Exactly Howard.  It is about 1"X2½" X 5'.  The length is so that it will nest in the back of the truck with the cant hooks, and the dimensions work out perfectly for edging.

In 15 years of sawing, that is probably my 4th stick.  Broke my Stick  I see in this 2013 topic where I said that my present stick is Red Oak.  Maybe so, but at over 4 years old, it is a good one.