Custom hydraulic backhoe thumb

[Aquamoose]

Wow! Did have to cut the panels to make them fit and drill new holes to keep the valves centered?

 

[Ron50]

Yes it did require using a cut off wheel on small Makita grinder and drilling four new mountng holes to keep things centered. Hardest part was working with Walvoil to get the correct valve. So many choices when it comes to hydraulics. Hydraulic Controls in Phoenix was a big help in ordering the correct valve. I used the same cylinder that Bumperm suggested. I first thought about doing this a year ago. Just now finished it up.

 

[Aquamoose]

Amazing work. Did you get the chance to operate it? What tractor do you have? What's the last picture of? I see rear remotes, on both sides?

 

[downsizingnow48]

Very slick!

 

[dfkrug]

I installed a handle that is two inches taller than the stabilizer handles right in the
middle of all the handles.

As I pointed out early in this thread, adding another spool valve to the stack is one of several
approaches to adding the valve for an hyd thumb. Glad someone has done it.

How it is controlled (hand lever, foot pedal, joystick button, or console switch) is important
and different approaches will appeal differently to different users.

One thing you get with an added stack valve is parallel inlet flow, so you can operate the
bkt and thumb cyl simultaneously and the combo behaves like a grapple.

Costs are substantially higher with this approach, however, and you still have 2 long hoses
that need to be routed up the outside of the boom and dipper.

 

[Ron50]

I've picked up a few big landscape rocks and it worked like it should. I have a Branson 4020R that I bought in 2012 to clear land in Oregon. I got the backhoe for it about a year and a half ago to build retaining walls and excavate for a detached garage. "Still working on getting a permit for that"!
The last picture shows the rear remotes which must be different than yours. I bought one single on the right, new with the tractor. Then I decided to add top and tilt. Easy, I'll just move the single to the left side and add a new double valve on the right for the top and tilt. Wait, as long as I am moving the single to the left side where the mounting holes can accept either a single or double valve I might as well make it into a double valve. I ordered the parts to add another valve to my existing single to make it a double as well. Sort of like a snowball rolling down a hill, I just hope that I have reached the bottom. You could connect the two valves with solid lines if you are good. I chose to use flexible lines because it was easier for me. The valves and mounting plate are how Branson did rear remotes in 2012.
The backhoe is plugged in on the left side in the last picture. I just hold the lever open with a bungee cord when useing the backhoe. This seems to have no affect on the use of the loader when the rear remote is open. Because loader and backhoe are both Ansung they are made to fit together. The subrame of the backhoe attaches to a solid round tube of the loader subframe in front, and to the lower three point hitch arm brackets on the axels in the rear.
Removing backhoe only requires pulling two pins in front, supporting on stablizers, unplug hydraulics and drive away. Takes as long to put three point hich assembly back on as it does to remove backhoe. I have since built a dolley to unload it on which actually makes it easier to reattach.

 

[Aquamoose]

Awesome Ron!

Glad it's working out for you. I'm going to try a foot pedal setup. Routing the hoses to the cylinder is going to be easy so I have no concerns there.

Mine's a 2015 3520h and I ordered dual rear remotes and a front 3rd function. Like you, I built a dolly for my BH in a way that fits under my pallet rack at 37" wide. (grin)

All I need is to get a ripper for the BH so I can put it to good use. With the hydraulic thumb, it'd be very versatile working with the stumps and rocks!

 

[Ron50]

I found the seat to be a little tight so I added more legroom. I added a piece if 3" x 5" steet tube beween the mount on the seat and the mount on the bh frame. This moved the seat 3" toward the tractor which made it more comfortable for me. Just saying in case someone else might be interested.

 

[Aquamoose]

This is an old thread, but I have a newer tractor, and one with a mechanical thumb on a BH77. Giving Dave credit, I shamelessly copied his idea on paralleling the curl cylinder. Works great! (thanks Dave). Here's some pictures and notes:



I used this 2 X 20 cylinder as it has adjustable port positions which I thought good in this app. Shopping



Close up of Hydraforce solenoid valve. Had to special order from one of their distributors - they wouldn't sell direct. I had to use two fittings to attach it to cylinder as the SAE 8 to 6 90* was out of stock - When I get it, I'll remount and also install a bracket for the valve - it is probably sturdy enough if you don't bonk it.





Taken before wiring Solenoid.



I wanted the waterproof push button switch on the joystick. Switch from Amazon, aluminum bracket from my little machine shop.



Finished switch install, shrink wrap on joystick shaft to keep it clean.



I used a Powerlet jack and plug (also referred to as Bosch or BMW plugs - and may be still sold by JD dealers) to plug into the tractor's 12VDC. One neat "happy" was that Kubota, on the B50 series, supplies a wired plug end at the left rear of the tractor AND the plug is a match for the Powerlet waterproof outlet - - how cool is that?!

http://www.powerlet.com/shop-by-product/plugs-sockets-wire-more/PWRDIST



One little "oops" occurred at the rod end of the cylinder. I needed about .360 more width, so made two .180" spacers. However, once installed, the ram end didn't end up on the pin centered - - took both spacers on one side (shown) to fit up nicely - guess this is due to a slight misalignment on the dipper stick bracket from the factory.

There was probably enough slack between the 25mm pins and the 1 inch cylinder end holes so the ram would have centered, but I used .012" brass shim stock to make bushings which took most all the slop out.

Tested it picking up a big rock - works great! And no more having to get off the tractor to deploy or put away the thumb.

bumper

Any chance of pictures? I really want to do my BH76 (Branson) and I already found the perfect cylinder for it.

 

[dfkrug]

Any chance of pictures?

It has been almost 10y since I started this thread, and the pix I posted are still there.

Picasa and Photobucket, and other free posting services are dangerous places to entrust your
photos, as we can see above. TBN still has all the ones I have posted on the site, and I am well over 1000.