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Operation

This section contains information about the actual operation of the GroundSaw.  Hopefully I can add to it when I get my GroundSaw operational.

 

I spoke to someone that owns three ground saws and knows a lot about them.  When trenching the machine is moved forward by a hydraulic motor that drives the tractor through the rear PTO.  To disengage the clutch and drive shaft, the clutch pedal is locked down.  To deactivate the brake (which would be on if the clutch/brake pedal was locked down) the linkage that connects the clutch/brake pedal to the brake was removed and a new brake pedal was installed on the right hand side of the tractor.  This worked ok but was really hard on the clutch and throw out bearing; it was like you were riding the clutch all the time.  The gentlemen I spoke to got around this by installing a creeper with the planetary gears removed.  He could then use the creeper to disengage the drive shaft when he was digging and didn’t have to lock the clutch pedal down.  I thought that was a really clever solution.

 

The Model 1200 that I own also has a “traction control” on it.  Since I haven’t used my groundsaw enough to completely verify how it works, I’ll tell you what the literature says.  According to the literature, the traction control “senses” how hard the saw is working.  If the ground is hard, the traction control slows down the ground speed.  In easy digging, it speeds up the tractor.  It’s adjusted by a knob on the front of the control panel.  I don’t know how it works, but there are a lot of small hydraulic hoses running between it and the other control valves.  It almost seems like some sort of pressure relief valve.  I’m not sure I’ll ever use my groundsaw enough to actually sense it working, but, if I do, you’ll read about it here.

 

 

Below is a picture of the contol panel on the groundsaw.  The control on the far left is to raise and lower the “boom”, i.e., the digger arm.  The middle control starts and stops the chain and initiates forward motion of the tractor.  The top right control is the “transport” control, i.e., the control that moves the tractor forward or backward when the chain is not engaged.  The bottom right control adjusts the “traction” control, i.e., adjust the transport rate based on how hard the ground is to dig.

ground saw oper pic 1

 Below is a schematic for the control system.  The rectangular box on the left represents the valve that controls the chain drive.  The center box represents the transport valve and the right box represent the traction control.  The circles represent the inlet and outlet ports for each valve.  The lines connecting the ports represent the small hydraulic lines that run between the valves and the traction control.

ground saw oper pic 2

 

In the picture below you can see the connection for the small hydraulic line connects to the outlet port of the transport valve.  The round cylinder on the left is the traction control.  The adjustment handle has been removed.

 ground saw oper pic 3

 

 

In the picture below you can see the two connections on the right are where the small hydraulic lines connect to the traction control.  The small connection on the left is the connection to the inlet port of the transport valve.

ground saw oper pic 4

 

 

The picture below shows the small hydraulic connection to the inlet port of the digger chain control valve.

 ground saw oper pic 5

 ground saw oper pic 6

 

Addendum: If you’ve checked out the video, you can see that I got to try out the groundsaw. I had assumed while digging, the groundsaw’s forward motion would be initiated using the “transport” control. That’s not the way it works. As soon as I engaged the valve that controls the digging chain, the tractor moved forward. There is obviously enough hydraulic fluid bypassing the digging motor to drive the hydraulic motor connected to the rear PTO. The transport control valve is only used when moving the groundsaw around when you’re not digging.

 

When I spoke to another person that reguarly uses a groundsaw, he pointed out a couple things about the video I posted. For one, he pointed out that if I were digging deeper or in harder, rocky ground the groundsaw would adjust to a much slower speed. Secondly he pointed out that the hydraulic cylinder that positions the blade in the ground takes a lot of abuse by the hammering produced by the chain teeth digging. He said that cylinder typically requires rebuilding. I noticed my cylinder leaks down rather quickly and didn’t do a good job of keeping the blade in the ground.

 

Also, I disconnected the Cub Cadet brake linkage and installed an auxilary brake. For some reason it seems to really work the engine to move the Cub Cadet around using the transport valve. When I was actually digging with the groundsaw, it didn’t seem to work the engine at all. But the transport valve seemed to really pull the engine down.

 

It took so much work to rebuild the groundsaw and get it going that I may not dig with it again. But, if I do, you’ll see or read about it here.

 

 

Last Modified On: 2014-11-11 17:06:58