I just purchased my first band sawmill. I have run 3 other mills in the past, but at that time I lived out west and we sawed mainly softwoods. I purchased a manual mill with 19" v-belt pulley wheels, and a 20 hp Kholer made by Boardwalk. The mill is set up to run 1 1/4" x 161" blades. I am ordering blades from Wood-Mizer because I like their re-sharp program.
My question is what hook angle and blade thickness work best for sawing crotch wood, and how much does sawing crotch wood shorten the time your blades stay sharp? Also, what do you use for blade lube with hardwoods? We used either diesel with bar oil, or pinesol cleaner and water for softwoods.
First off, welcome aboard :)
I'm also running 1-1/4" blades, but I don't know what the hook angle or anything is :-\ I run Lennox woodmaster C blades. Straight water for lube here, maybe a little soap if I'm cutting really pitchy logs.
I find the blades have to be pretty sharp for cutting crotches, but mainly because it's usually a pretty wide cut that is being made. The biggest thing I've found with cutting crotches is that the cut goes much better if you cut "up" the log (from the ground up, if the tree were standing).
Quote from: ohsoloco on April 10, 2006, 10:30:33 PM
I've found with cutting crotches is that the cut goes much better if you cut "up" the log (from the ground up, if the tree were standing).
Hmmmm ........... never noticed that. What reaction does it have comming from the other direction? Entering the cut at the top (no crotch) has always given me a straighter cut rather than entering the butt first.
I have cut them from top to bottom , will try out the bottom to top .
As for your blade angles , when orfering your blades from WoodMizer ask them , they will sugest the best blade for what you will be sawing .
Nice sharp ones and change as soon as you notice a bit of deviance
iain
I'd go with the thickest and widest blade your mill can pull and not bogg down. Wood-Mizer makes a blade with a 4 degree hook angle for forzen wood. That may work the best.
We're using 1-1/4x.055 with 9 degree hook angle as a first choice to saw our walnut. We saw a lot of big logs with big knots and such.
In any real hard sawing, make sure your main drive belt is not slipping.
Woodbowl, a few years ago when I was milling some walnut crotches I started from the crotch end, and noticed that my blade wandered quite a bit (ie rising and falling). Ever since then I mill them the other way, and haven't noticed the problem as much. Perhaps it has to do with the fact that the crotch end is usually so much wider than the other end...I can't really say, but it works for me.
I agree with you as far as entering the log from the top if there isn't a crotch, that's how I mill almost all of my logs. Although, my blade likes to dive in the last foot of a log that has a lot of butt swell.
Sharp and as Bibby mentioned not a lot of hook angle...bout all the crotch wood I cut is between 24 and 29" wide. Also tension the band to the max.
If ya get little wave or something not to worry...there gonna twist and warp as they dry anyhow. Cut em extra thick to allow for processing when dry.
Take time to enjoy the wonders of walnut as you saw...your gonna see some of the prettiest greens, blues, purples, browns, and blacks known to man. A lot of the colors will disappear in a short time. :)