Need technical advise

[lighthouse]

I need an attachment to clear a mile of brush for a utility easement for my property, and have been researching tree saws. However they are not cost effective to buy, and I can find only one place that will rent one and they want over $800 a week. So I am going to build one. I am pretty good with my welders so the metal fabrication won't be an issue. I have been researching hydruallic motors, and am not sure which one will work best for my purpose. My Bobcat 7753 is rated for 15gpm on the aux. hyd. From my research, I think I probably need something in a 8-10 cu in range. Assuming 2000psi and the 15 gpm, that would put me in the 3000+torque and 300 rpm range. Does anyone have an opinion or advise on the matter? I have no experience with hydruallic motors, so any help would be greatly appreciated. Thanks

 

[Tazza]

Surplus center on the net has a good hydraulic calculator to work out what CID you need on your motors to provide the desired output speed.
Just what are you trying to make? are you trying to construct a slasher or an actual saw? You will need some serious torque to really tear into the brush, possibly more than your machine can put out.

 

[lighthouse]

Surplus center on the net has a good hydraulic calculator to work out what CID you need on your motors to provide the desired output speed.
Just what are you trying to make? are you trying to construct a slasher or an actual saw? You will need some serious torque to really tear into the brush, possibly more than your machine can put out.

I'm hoping to build a tree saw like the ones sold for skidsteers using a 22"-32" circular saw blade. I only need it to cut down trees no bigger than 2"-3" in diameter. Anything bigger I will use a chainsaw on. The specs I have found on the ones for sale vary, but are around 200-300 rpms and 3000-4000 lbs of torque on a 15gpm flow. Do you happen to know what the psi of the aux hyd on a 7753 are?? I am using 2000psi as my base line for my calculations. But it would help to know if that is correct. Thanks for your help.

 

[OldMachinist]

I'm hoping to build a tree saw like the ones sold for skidsteers using a 22"-32" circular saw blade. I only need it to cut down trees no bigger than 2"-3" in diameter. Anything bigger I will use a chainsaw on. The specs I have found on the ones for sale vary, but are around 200-300 rpms and 3000-4000 lbs of torque on a 15gpm flow. Do you happen to know what the psi of the aux hyd on a 7753 are?? I am using 2000psi as my base line for my calculations. But it would help to know if that is correct. Thanks for your help.

 

[Tazza]

That speed seems a little slow to me for a circular saw blade, but i guess with that much torque, it would still chew through it.