shaft OHC motor and a set of massive worm gears . What is the overall
reduction in your drive train , and do you think 6 horses is enough ?
More to the point , what is considered a good feet-per-minute speed for
the band ? This motor came from a pressure washer or maybe a log
splitter that had a pump failure and is governed at one speed . I bought
it for a tiller I have - and no longer need (got a rear tine now). So
now I'm considering going ahead and building a band mill that will
handle up to 12 foot logs up to a couple of feet in diameter. Build will
be similar to yours , with the power head assembly on jack screws .
I followed Suffolk's recommendation of a 1-1/4" wide, 3/4" pitch,
0.045" thick silicon steel Timberwolf blade running 5000 feet per
minute, lubricated with bar oil + kerosine from a spray bottle. The
blade stock was welded to fit my measurement.
The Lovejoy L099 coupler on the 6.5HP engine shaft has held up so far
although it gets quite warm. The rubber spider of an L095 didn't last
long. My motorcycle wheels are quite heavy and the engine has trouble
accelerating them at idle, so I slip the manual clutch. The drive
train geometry isn't right for a go-kart centrifugal clutch with a
chain sprocket, though that might have been better.
The Suffolk tech suggested that my blade guide arrangment might be
contributing to the blade rising or falling in the cut when it starts
to dull. The guides are supposed to lower the blade 1/8" to stiffen it
from twisting while allowing 0.005"-010" clearance underneath for
sawdust. Suffolk uses 6201 bearings in their guides.
6.5HP cuts 12" oak with a sharp blade at about 1" per second. It can
manage up to 20" with some difficulty which increases as the blade
dulls. Right now blade deflection limits how hard I can push and more
HP wouldn't really help. Since I'm cutting beams or 10" planks there's
only one full thickness cut per log. I'd say 5.5 - 6.5HP is adequate
for hobby use but not to make any money.
I sized the capacity for the max diameter of my trees at 6-8' above
the ground. If the saw frame won't clear the butt end of a log I slab
it with a chainsaw. Another consideration is the width of your planer.
Handling the half ton logs was very slow and difficult until I built a
gantry hoist crosswise above the center of the track. They are easy to
rotate when hanging from a rope sling running through a pulley.
Waxing the ends of green logs slows drying enough to greatly reduce
cracking. I brush on molten toilet ring wax, which is less brittle
when cold than canning paraffin.
thing - one more question (for now) . What did you use for the frame
that carries the wheels , 2" heavy wall square tube ? . I'll probably
use beeswax on the ends of logs though most of my stuff may be cut green
and seasoned as planks . My goal is to side my house with white oak
board/batten from trees cut on our land . There are some very nice 16"
plus diameter trees deep in the woods , and they grow close together so
Yes, that part is a straight ladder frame of 2" square tubing. The
wheel axles are hung below it to maximize the throat depth. The saw
track and upright frame and overhad gantry hoist tracks are 3" channel
that was cheap surplus pallet rack. The blade guards are wood to avoid
damaging the teeth when installing a blade.
C3 x 4.1 channel is more than stiff enough but perhaps overpriced if
bought new. Commercial band mill tracks are angle iron, which sheds
sawdust better than my flat-topped track. OTOH mine spans 8' between
leveling feet so it's simple to set and keep level. The log supports
are separate, only the saw weighs down the track. I don't have any
smooth level ground to support the one-piece track that commercial
saws use and mine looks like an elevated railroad trestle, the ties
being doubled 2x6's with 3/4"-10 adjusting screws at the ends.
My first bandsaw mill was built on a trailer that could be tilted with
the tongue jack to self-feed by gravity. Since it used a 1/2 HP
electric motor it didn't have the runaway problem of a vibrating gas
powered saw, but it took half an hour to cut a 10" x 8' plank. I set
this one as level as possible and then level the blade, the log
supports and the cants when squaring them. It's like leveling a lathe
or mill, you don't really have to but it gives you an easy measurement
I originally thought the vertical throat depth should be at least half
the 20" width capacity so I could cut a log on the diameter, but in
practice I first slab large logs square to inspect them for defects
and stabilize them on their supports, so for example I cut off 2" or
less slabs and planks to give a 12" square cant and then slice it into
two 6" x 12" beams or four 6" columns. 7"-8" would have been enough
Maximum log length is 4' less than the track length, 2' at each end,
because I may have to lift a log or sawn beam when the saw head is at
Building the frame required a 4x6 metalcutting bandsaw and a stick
welder. A lathe and mill were necessary for the moving parts,
especially to adapt those not intended to work together. I think you
could use cam followers to simplify the job. I machined the needle
bearing track wheels and column rollers from scratch. The needles are
I've cut some oak green and some that air-dried for many years. The
green planks gave less trouble from cracking but more from cupping
despite being stickered fairly closely and stacked under heavier
beams. I didn't quarter-saw any. 10" x 1-1/2" rough planks mostly had
to be planed to 1-1/8" to remove all cupping.
The dried oak wasn't significantly more difficult to cut and blade
life has been about the same.
After considerable experimentation I found how to fairly efficiently
cut rough slabbed planks to width and make stickers (or battens) as
small as 3/4" square, using simple wooden fixtures. The details depend
on what you build, I'm just telling you it can be done easily. I
drilled the tracks for the swing-up metal F clamps commercial bandsaw
mills use but I haven't needed to make and install the clamps yet.
I sloped the corrugated roofing cover panels upward toward the center
overlap with stickers of increasing width, turned on edge. They're
(mostly) all the same 1" thickness but their width is whatever
thickness the reject planks were when I cut to the beam outlines
traced onto the ends of the log.
I think I covered the major design considerations as well as I
remember them from 12 years ago. The construction details depended on
what I had on hand or could scrounge up, so it may not be a good model
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