power requirements for circular saw

[jonboy]

Hi all....its been a year since my last confe...er, post ...hope you're all well and getting wet now and then....

Just picked up some used but good circular saw blades...between 14,5 and 17 inches, 37 - 44 cms dia. and thought I'd make a ripping table... various single phase motors knocking around... what's going to be a minimum horsepower or wattage to drive that size blade, and for ripping up to 6" 15cm old pine beams..... and if I go for gearing... whats the max revs a blade of standard set, no tungsten tips type is best at? good to be back J.

[Bob Cleek]

I'd say forget about it. (Sorry!) Blades that size generate substantial speed (at the outside edges) and power. You are going to have to think about arbor mounting and structure, adjusting ability and so on. I'd think you'd do a lot better to get yourself a standard 10" cabinet saw like a Unisaw or Grizzly or Jet knockoff. Used, a good 3HP Unisaw or equivalent shouldn't run you more that $850. Blades, etc are easy to come by. You should be able to cut 6" on one if you go slow and easier still by taking two 3" cuts, one from each side. Safety is an issue. A 17" circular saw blade is serious business. Hang them from a cord and use them as wind chimes!

[Ron Williamson]

Big panel saws use about 5-6 kw.
R

[Gib Etheridge]

Makita model 5402NA 16 15/16" circular saw uses 120V/15A at 2200RPM, used for cutting beams.

120V times 15A = 1800 W.

1800W divided by 750W = 2.4 HP

Make sure your blade is newly sharpened and set for ripping, you may have crosscut blades. Cutting that much depth it will make a big difference. I would just use the biggest motor you have, minimum 15A.

[PeterSibley]

I'd suggest a 10 hp diesel or better, calculate rim speed at around 5000 feet per minute. Use a 7/8" arbor minimum ,use a reeving knife, don't stand behind the thing. If it jams and throws timber back at you it will spear you right through your belly. It's happened to a man I knew, a 14 foot 2"x2" speared him right through, ended about half way. He lived which surprised everyone.

Alternatively take Mr Cleek's advice and use the blades as decoration and build a bandmill. A lot safer and they will do exactly what you are asking .http://www.diybandmill.com/