Rotating Logs for Quarter-Sawing
Thoughts on rigging a swing-blade mill to spin logs after every few cuts, in order to produce a high yield of quarter-sawn lumber. October 3, 2009
We have an L. mill and it is a very cool and simple machine. I'd like to rig something to make it cut all VG material by taking a deep cut, then spinning the log after 2-3 boards. The log would be mounted on a central axel stub on each end and pivot on jack stands, like a rolling pin. Itís easy enough to weld up an 8" disk on a 6" long axel and lag it to the endgrain using a battery drill. Maybe a light hand winch to spin the thing fractional turns. You'd probably just do good, short logs, say 10' and pretty good diameter, of say 24" minimum. I think you'd get all quarter sawn (VG) material with a rig like this. Has anybody ever done something like this, or has it just been a waste of time thinking about it for the last two years?
(Sawing and Drying Forum)
From contributor S:
I say go for it. An overhead, end dogging scragg mill set near here uses a hydraulic cylinder to put end pressure on the log; a hydraulic motor is set up to spin the log 1/4 turn. Your idea sounds a little more labor intensive, just make your welds strong and use metal plate thatís heavy enough. I'm a little skeptical that lag bolts in end grain will hold a 24" log by the ends, but if you want to risk it, maybe it will work.
From contributor C:
Maybe a mod to the saw head would be easier?
From contributor T:
I think you'll have better luck using a heavy piece of flat bar in place of the round plate. It would allow for better clearance. You could weld a centering pin to it that would insert into a hole drilled in the center of the log. Then drill one hole each near the two ends to receive your bolts. If built heavy enough it would hold and spin it ok. But I think clearance and accidents will still rule. Can you guarantee that you won't hit it?
From contributor V:
It depends on your definition of VG. Swing mills do an outstanding job of cutting VG as configured from the factory depending on the wood. I can cut a douglas fir 80%-85% what passes as VG without moving the log. The ability to cut horizontal or vertical is really neat. I always start by opening the top of the log to get a flat reference plan. To get just a bit more VG why not think about propping up one side of the mill say 7", cut to the center of the log, take out the blocking, cut through the center portion, and then for exit block the other side of the mill up.
If you've got a nice round log and are using notched "dogs" you could just roll the log in the notches to get the same effect. Just my two cents and cuts down on the extra "equipment" to haul around.
To get just a little more VG one other trick I've used for the bottom half of the log is to cut down 8" horizontal to establish a flat side and then turn the log 90 degrees so it rest on that flat. I use metal gogs on steel rails (may have notch any uncut edge to clear the rails). Flatten the now top and cut horizontal to the dogs. Itís lots of extra work to get a little extra VG anyway you do it.
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