DiskDoctr
Platinum Member
I went back and done the math agin. when I was posting I was working off memory, which isnt as good as it once was. Yea, I was way off.
The chain speed is based off the rpms X the circumference of the sprocket. The dia of the 12 tooth sprocket is 2.75 xpie'=cic of 8.639 inches. Multiply this times 3000 rpms=25917inches per min/by 12in=2160fpm. A 5000rpm motor would yield a speed of 3600fpm and i believe this to be the number I was actually trying to remember when I originally posted.
Just for info, the dia of the 14tooth sprocket is 3 5/16 or 3.3125 x's Pie=10.406x's 3000rpms=31218 ipm/12=2601fpm and at 5000rpms=4335fpm
I am not sure of the max rpms of the cross motors, the 3000rpms is based on 15gpm flow, you may or maynot be able to increase the speed of the motor by throwing more flow at it, but i dont know how safe that might be or how long the motor would last.
Also, if you choose to use the 14tooth sprocket, keep the bar as close to the sprocket as possible to reduce the likelyhood of chain throw. Use a bar with a width similar to the diameter of the sprocket. A narrow bar will cause the chain to rideup out of the guide rail of the bar and jump off the sprocket. A wider bar will also allow for more ajustability when you start to encounter chain stretch.
Muddstopper-
Thanks for the updated info. I'm glad there was an error in your figuring. I certainly wasn't trying to be know-it-all or anything. I am going based on what I've read- and OPW (Other People's Work), so I was asking about your calcs.
What you posted now seems to be pretty consistent with the other info. I was a bit concerned my info was wrong
I may be looking at a smaller hydraulic saw setup. I'm planning to go see one of the saws "in action" next month- thanks to a very generous offer to allow me to drool over...uhm...look at :drool: someone else's project
I'll keep you all up to date on how we make out!
Thanks again for everyone's input.
- JC