Adding two hyd remotes to Kubota

[nealfris]

My layout now: L3000DT w/ LA 452s loader and Woods 7500 BH powered by PB from loader controls rather than PTO pump. It appears to me (not knowledgeable with hydraulics) the supply comes out of back top of trans., goes to loader in. PB to BH. Return from loader goes to left side of trans w/ return from BH connected to a block bolted over power steering block.
I would like to add two remotes, one for elec over hyd for front grapple and one for a home made boom mower with hydraulic motor or what ever else is attached to back, ie. hyd thumb. Can I simple T off something rather than the seemingly in depth remotes as scene in Everything Attachments video? Can I get separate components from Surplus rather than buy pricey bundled remotes?
I am very mechanically inclined, just not up to speed on hydraulics.

Now for the fun!!! Need help with boom mower math. I am using an old heavy duty 30" single blade JD mower deck w/ 28" blade attached to BH arm at bucket pins. Uses include grass and light brush only, reaching over banks and maintaining long drainage ditches.
My specific questions are: Is 6.9 gal min enough to run a hyd motor? What kind of valve do I need to run hyd motor? What model hyd motor would make all this work? I plan to mount the motor offset from blade pulley so as to work out rpm ratios and protect works with sacrificial belt. What is the math for figuring out hyd motor rpm all the way to blade tip speed. ie. pulley sizes, motor rpm etc.
Also should I put an extra filter in somewhere to prevent contamination.
Thanks and look forward to your input.

 

[kennyd]

Re: Another Hyd. remote question (sorry)

My layout now: L3000DT w/ LA 452s loader and Woods 7500 BH powered by PB from loader controls rather than PTO pump. It appears to me (not knowledgeable with hydraulics) the supply comes out of back top of trans., goes to loader in. PB to BH. Return from loader goes to left side of trans w/ return from BH connected to a block bolted over power steering block.
I would like to add two remotes, one for elec over hyd for front grapple and one for a home made boom mower with hydraulic motor or what ever else is attached to back, ie. hyd thumb. Can I simple T off something rather than the seemingly in depth remotes as scene in Everything Attachments video? Can I get separate components from Surplus rather than buy pricey bundled remotes?
I am very mechanically inclined, just not up to speed on hydraulics.

No, you cannot Tee into any high pressure lines, all valves must be added in series. The only line you can Tee is the low pressure return line (OUT line form the loader valve to the tranny)

You can get all the parts from the SC-no problem.

Now for the fun!!! Need help with boom mower math. I am using an old heavy duty 30" single blade JD mower deck w/ 28" blade attached to BH arm at bucket pins. Uses include grass and light brush only, reaching over banks and maintaining long drainage ditches.
My specific questions are: Is 6.9 gal min enough to run a hyd motor? What kind of valve do I need to run hyd motor? What model hyd motor would make all this work? I plan to mount the motor offset from blade pulley so as to work out rpm ratios and protect works with sacrificial belt. What is the math for figuring out hyd motor rpm all the way to blade tip speed. ie. pulley sizes, motor rpm etc.
Also should I put an extra filter in somewhere to prevent contamination.
Thanks and look forward to your input.

You will not be happy with the performance of the motor on a 30" mower with only 6.9 GPM.

 

[J_J]

Re: Another Hyd. remote question (sorry)

Kenny is right for the following reasons. To produce the 6.9 GPM's, at 3000 psi requires 14 HP. The pump will lose some HP due to efficiency, which brings that to 11.9 HP. The hyd motor also has an 85% efficiency. Now if you run those GPM's through a hyd motor, with 2 cu in displacement, the rpm of the hyd motor will be 797 rpm, and if you work out the ft per min on the 30 in bld tip, you will have about 4280 ft per min. No where near enough for efficient cutting. You need somewhere around 16,000 to 20,000 bld tip ft per min, for some efficient cutting.




Now if you provide that same motor with 20 GPM's, the rpm of the hyd motor goes to 2310, and that produces a bld tip speed of 12,358 ft per min. Still not good enough but will cut somewhat.

You need 41 HP to drive that 20 GPM pump.

To run a hyd motor, a motor spool valve will let you operate the hyd motor with free wheeling after valve is off. Could be a detent motor, or a variable speed valve like this.


https://www.surpluscenter.com/item.asp?item=9-064-38&catname=hydraulic

 

[nealfris]

Thanks guys. Trying to understand. I think my worst fears are coming to light. Manual says my tractor is 32.1 hp 2205 psi. Motor will be offset so I can multiply rpm to blade using different dia pulleys? Is torque the problem? The mower deck came off a mower with only 10 hp motor.

 

[J_J]

Yes, you will lose some torque. It takes about 11 HP to run your pump at 2205 psi. AS you go from from pump to motor, you lose HP So you would only be developing about 8 or 9 HP for the deck.

The take off deck on the JD mower was probably driven at engine speed of about 3600 rpm. That would give about 19,260 ft per min, which would cut as expected.

Why not use a 2 stroke small engine and mount it on a boom off the 3pt, and use another hyd valve to articulate the boom and tilt.

 

[nealfris]

Sorry to be slow on the uptake! Not getting the first part. Are you saying that my engine is 32 hp but only 11 hp @ my internal pump?
Also, can anybody enlighten me on the remotes scenario I mentioned???

 

[J_J]

Yes, it takes 11 HP to run that pump and when that energy is transferred to the hyd motor. It will produce less HP to the attachment.mower. Actually, you are only using that HP when you are using the hyd to the max. If you are not using any hyd, then the 32 HP will go to the drive, and/or provide about 30 HP to the PTO.

The remainder of the HP is used to drive the machine.

 

[nealfris]

Thanks JJ for your input and your patience!

 

[nealfris]

Just wondering, My pto is not being used with this configuration. Could I use a pto pump and get a better hyd output for the motor?

 

[kennyd]

Just wondering, My pto is not being used with this configuration. Could I use a pto pump and get a better hyd output for the motor?

Sure, but at quite a cost. Pumps are near $500, you would also need a tank ideally equal to the GPM of the pump, filter and large hoses also.

Also, can anybody enlighten me on the remotes scenario I mentioned???

I thought I did?