I ran a 30" cordwood saw years back. Nasty beast. Used a sliding table
rather than moving the arbor. I'm guessing it ran in the 900 rpm range
(hard to know exactly since the drive mechanism was NON STANDARD!!) The
30" saw was used on huge piles of green birch running up to about 8",
would slice it like butter. Saw teeth were on the order of an inch high,
1-1/2" tooth to tooth. (As in .6 teeth per inch?)
Found these pics:
http://www.americanartifacts.com/smma/advert/ax24.htm
http://www.antiquetractors.com/content/yph4283.htm
http://www.americanartifacts.com/smma/dragsaw/ds23.gif
http://www.americanartifacts.com/smma/dragsaw/ds29.gif
http://www.americanartifacts.com/smma/dragsaw/ds26.gif
http://www.tractorshed.com/photoads/upload/35381.jpg
For your 18", 3hp would be a good start, 5hp would be better. You would
want double 'V' belts, notched belts would be better. I'd try for around
1800 rpm which means finding an 1800 rpm motor so you could get a 1:1
pulley setup.
I don't think you will like the 18" blade, too small once you deal with
the arbor, bearings, and pulley. Hard to get more that 6" to 7" of
actual cut diameter. Keep in mind that logs have curves and knots. You
really need some guards that both work to keep hands out and work with
logs that are not anywhere near as straight as cheap 2x4's
I'll second Grant's phobia about saws like this. BTDT, still have all my
fingers and hands. Not sure why I was so lucky.
Grant Erwin wrote:
Laurie Forbes wrote:
Am contemplating constructing a wood cutting chop saw for cutting up
fireplace logs. 18" circular blades are readily available here and
would seem about the right size for the size of logs I'd be working
with. Question is, what HP electric motor would be required (about 3?)
and, what would be best RPM for the blade?
All suggestions appreciated.....
Laurie Forbes
7.5hp MINIMUM motor, and that's electric. If gas, make it 18hp.
Blade speed 3000 sfm. 1.5' diameter, 4.7' circumference, rpm = 636.
Figure 1760 rpm / 3 = 586 rpm, close enough, gear a 1760 motor down
3:1-ish.
This sounds *extremely* unsafe. Better type all your questions now while
you still have hands.
GWE