Hydraulic limb saw project.

[Smokeydog]

Just catching up here. I'm finding this very interesting Smokey. It is amazing how involved things get when you stop and think them through like you are doing. Glad you are posting your work !!

gg

Thanks for the feedback. Sure hope this works.

Just picked up the last of hydraulic fittings and got the experience of the local hydraulic shop to bless the motor and metering valve plumbing.

Last pieces are cut. About 4’ of welding left to do so getting to the short rows.

 

[Smokeydog]

Motor side.

Saw side. 9 tooth drive sprocket.

 

[Gordon Gould]

Looking good !!

It looks like you are bleeding off some hydraulic fluid on the pressure side to use as bar and chain oil .... am I seeing that right ??

gg

 

[Smokeydog]

Looking good !!

It looks like you are bleeding off some hydraulic fluid on the pressure side to use as bar and chain oil .... am I seeing that right ??

gg

Yes. Sees pressure when cutting. Built in check valve when not. Reversible motor to help back out of a pinch.

Will need to adjust to get the right amount of oil. This will run approximately 2340’/minute, a little less than half the typical chainsaw speed. But instant torque. Guesstimating starting at a drop every 4 seconds at no-load speed. 60/4=15 drops per minute. 15x60= 900drops per hour. 900/20=45ml/hr. 45/30=1.5 oz of oil per hour when the saw is running at no load. Guess a little more volume under load. Lower chain speed, less heat and oil throw off and seconds per cut are advantageous. A week of cutting may use 1-2 cups of oil? It’s going to be feature to monitor and adjust when using.

Did drill the chainsaw bar to have top oiling while mounted on the left.

Few short sided set backs.
The 15’ hydraulic hoses are too short. Boom and saw arm are longer than first planned. Ordered 5’ pair of extensions.

Typical 81 drive link saw chain too short. I started out modeling like my Husky 3/8” saw mount then switched to .325. Stud spacing and distance to drive sprocket all a little different. Need 83 drive links. They do make that loop size just not typical. Saw shop could custom make too.

Few features.
Using SS tethered ball release pins for saw arm adjustment anchors. Less to come apart or lose when using.

Saw arm motor mount 15*
off straight. Mimicking a manual polesaw curve to cut from the top down to help prevent pinching. Also improved max height geometry.

Not much left to complete and anxious to get to use.

 

[mike0000]

Very interesting project. I recently bought my first pole saw, I’m amazed at how much work I get done with it (also how quickly it makes a large brush pile).
Thanks for posting.

Mike

 

[BackRoad]

Mr. Smokeydog, does your design permit for an initial cut to the underside of a limb?

 

[jmc]

Is that a common thing, using hydraulic oil for chain oil? The chain oil I've used seemed stringy or sticky when you pour it, like lathe way oil, which has paraffin in it to keep it from wiping off the ways.

Really enjoying your workmanship.

 

[Smokeydog]

Mr. Smokeydog, does your design permit for an initial cut to the underside of a limb?

Short answer no. Can’t use the loader hydraulics to move the saw thru the cut. Not a good way to feel saw pressure. The saw arm is hinged so the weight is what carries saw thru the cut. Best to make several section cuts back to the trunk to reduce bark stripping. Time of year and some judicial use of manual polesaw could improve arborist results.

Could some coil over shock springs on the saw arm give a controlled force on the saw to also give an upward cut? Idea needs some clever development.

 

[Smokeydog]

Is that a common thing, using hydraulic oil for chain oil? The chain oil I've used seemed stringy or sticky when you pour it, like lathe way oil, which has paraffin in it to keep it from wiping off the ways.

Really enjoying your workmanship.

Common and convenient for hydraulic saws. There are other options too.

 

[newbury]

Have you thought of mounting some sort of camera to view live video to help you to maneuver the sawhead in tight places? Like a backup cam?