Custom hydraulic backhoe thumb

[dfkrug]

D, I think you are confusing a "diverter" and "valve" in this discussion, diverters do not have
a center position, they are either switched one way or the other to direct flow from a valve. What you see from WR and
SC mounted on a subplate are NOT diverter's, but rather solenoid operated control valves plumbed in to the PB lines-that's
why they have two opposing solenoids that move the spool one way other the other to operate a function.

I am not confusing them. I just described them above.

There are 2 approaches to this problem: get hyd power from an existing circuit (curl in this case), or add another
valve in series to all the other valves powered by the implement pump

 

[avc8130]

I got mine all installed, plumbed and wired. I need to take pictures.

I dug a trench today in a rocky area. I LOVE having the thumb. I am SO glad I went this route with the hydraulic rather than a mechanical. I would find rocks in the trench and just hit the button and pinch them. No fumbling. I could do everything without moving from the seat.

The ONLY issue I found was that placing the rock back down was more difficult. With a "real" hydraulic thumb you can collapse/pinch the thumb WHILE uncurling the bucket. This lets you "pivot" the load and "place" it. Can't do that with this setup.

Honestly, for the money spent and the ease of install it's just silly NOT to have a hydraulic thumb.

ac

 

[lhansman]

I look forward to seeing the photos of you thumb setup Anthony.

Regards,

Lauren

 

[avc8130]

I look forward to seeing the photos of you thumb setup Anthony.

Regards,

Lauren

Next time I have it out from behind the garage. Probably over the weekend honestly unless I get around to doing the 300 hour services sooner.

ac

 

[MEMEMEME]

Next time I have it out from behind the garage. Probably over the weekend honestly unless I get around to doing the 300 hour services sooner.

ac

I know this is an old thread but I can't stand the suspense any longer...really want to see the pics!

 

[MEMEMEME]

I've looked for quite awhile for one of the valves you guys have listed with no luck, finally found THIS one: HYDRAFORCE SV10-21-8T-N-12DS Hydraulic Valve

Will this do the job on a thumb on an old Case 530CK with a ~ 20 gpm pump @ 2000 psi?

Thanks in advance-

 

[dfkrug]

I've looked for quite awhile for one of the valves you guys have listed with
no luck, finally found THIS one: HYDRAFORCE SV10-21-8T-N-12DS Hydraulic Valve

Will this do the job on a thumb on an old Case 530CK with a ~ 20 gpm pump @ 2000 psi?

Given all the options on these valves, you should prob order exactly what works best for
you. To decode the options on the valve you found, Hydraforce provides free PDF catalogs
you can view online, or save to your computer.

At a glance, I see this one has 1/2 (-8) ports, which is pretty large, so it would likely be
OK for your flow rate. As for the logic of an SV10-21, check the catalog.

 

[bumperm]

I think it is preferable to use a normally closed valve if you are installing on a Kubota or other tractor that has an always hot* 12volt aux output at the rear of the tractor. That way the thumb is off with no power applied and solenoid current, when the tractor is parked, won't be draining your battery if you forget to unplug or turn thumb power off. With a normally closed solenoid this isn't an issue as power is only applied when you want the thumb to move.

Course one could always wire up forward to a "ignition" switched source.

*I installed a rocker switch in the wire to the rear AUX output on my tractor. Reason is I installed a solenoid valve on my boom sprayer so a can quickly shut off the spray for turns etc. To facilitate using the 12 volt outlet for different equipment, it's wired to a powerlet socket (also called Bosch BMW style): Plugs Sockets Wire & More - Powerlet Products

Much better and more reliable than a cigarette lighter style outlet, smaller too. Used to be used and sold by John Deere dealers too, maybe still is.

 

[dfkrug]

Course one could always wire up forward to a "ignition" switched source.

For the diverter application in this thread, you must use a switched source for the
solenoid valve. Left ON, the FEL curl control operates both the thumb cyl and the
bkt cyl at the same time. I have left it ON and forgotten it, numerous times. It
will drain the battery if you don't use a switched source.

 

[bumperm]

If you are using a normally closed solenoid valve, and a momentary push button to apply power to that solenoid only when you want the thumb to move, then it is not necessary to use switched power, it can be on constant as it's not applied to the solenoid until the button is pushed. No battery drain.



Momentary push button on dipper/bucket curl joystick.