FEL Grapple from Scratch W/ Lots-O-Pics

[davemudge]

I have a Mahendra 28 series with a front loader. Building the grapple and associated mounts etc. is no problem. I am shop manager in a small machine / fabrication shop. I am wondering about the hyd. connections and controls. Does anyone have any advice specific to Mahendra? http://www.tractorbynet.com/forums/images/smilies/confused.gif

 

[3RRL]

Hello Scott, long no see !!:thumbsup:

I have a Mahendra 28 series with a front loader. Building the grapple and associated mounts etc. is no problem. I am shop manager in a small machine / fabrication shop. I am wondering about the hyd. connections and controls. Does anyone have any advice specific to Mahendra? http://www.tractorbynet.com/forums/images/smilies/confused.gif

Dave,
If you go to Larry's post #2, 22, 27 and 37 (and maybe others) he lists the components you need (and where to get them) and also the hydraulic circuit. Your Mahindra hydraulic circuit is most likely an "open center" circuit like most of our tractors. The plumbing concept is identical.
Rob-

 

[GuglioLS]

Yeah...... too bad it doesn't look like Larry participates here anymore.

I'm still here.

No new amazing projects to post . I admit to being sort of MIA lately. Been kind of tied up with a new product introduction at my day job. No end in sight to my work schedule either, sure beats the alternative though.

I find it amazing this old thread has been brought back to life, it's been almost 5 years and 46,840 hits later and the grapple is still going strong, no mishaps either. It has been re-painted and touched up a few times. I've help design and plasma cut a few more grapples but no longer have much time to devote to my hobby. To this very day Rob and I continue to get requests for his original plans to this grapple!

I just checked a few of my other several year old build it yourself project threads only to find they too have new activity and questions from members. Man am I in trouble Sorry for not getting back to you, I better get with the program.

Best regards,

Larry G

 

[Ductape]

Larry,
Good to see you check in. I'm sure we all have spurts where we are MIA for awhile. Looking forward to your next tractor project.

 

[tbutman]

you should sell "un welded" kits.

 

[GuglioLS]

you should sell "un welded" kits.

Tom,

Great idea for some hobby income when I retire. Finding proper hydraulic cylinder placement and jaw bracket location to get the open close geometry just right for a particular size and style bucket is not as easy as it looks. There is some science to it and somewhat of a "secret technique" to get the geometry correct. I call it (trick-o-nometry) :confused2: but the starting point is pretty much by trial and error. It's very time consuming. Allot of the inquiries think "one grapple design fits all" and this design will fit any ole bucket, but that's just not the case. There is an e-bay seller offering pre-fab grapples in various lengths. I'm sure they work great but for a perfect fit nothing beats a custom design.

Larry

 

[tbutman]

so one end of the piston mount will have 5 holes in a row and you explain one of them will work for your bucket. The user has to sink a bolt and do a few "no Load" tests to find out which one works best. Then they weld away until their hearts content. The point being you just gave people who like to build stuff the option of having a grapple bucket that don't have the equipment to cut their own materials or may not have the expertise to know basically how to plumb it through a valve body. Perhaps,that's the value in a kit like this in that your selling the possibility for someone to put a grapple on their bucket that may not have been a possibility to them otherwise. I don't think you will ever get Rich from such an endevour, but you can get paid for your time and have the satisfaction of knowing your doing a good thing.

 

[Reg]

I know this is an old thread, but still a GREAT one.
I am going through the "diverter valve vs long hoses from the back" issue on my smallest tractor.
Right now it is just for a grapple that I am not at all sure that I will have ENORMOUS amount of use for.
A front mount hydraulic post hole digger is a distinct possibility in the near term.... iffy/maybe.

Recent browsings around Surplus Supply have me wondering if the solenoid valve and base plate solution is still the best choice.
These;
Surplus Center - 12 VDC 10 GPM CC DA SOLENOID VALVE
Surplus Center - 1 STATION DO3 SUBPLATE CLOSED AND OPEN CENTER
Surplus Center - HIRSCHMANN CONNECTOR
were recommended a few years ago and are still available.

This;
Surplus Center - 12 VDC 13.2 GPM SAE 8 DOUBLE SELECTOR VALVE
Looks to be a bit more compact and "integrated", i.e. all one piece and ready to "plug and play".

My guess is that I would take the bucket curl/dump hoses from their current quick disconnects at the loader frame, route them into the diverter, then continue the normally open ports to the bucket curl/dump, the normally closed set going to grapple open/close - - Ooops, I just realized that "float" could be very desirable for grapple close...

The long hoses from the rear - - probably functional (enough), a little less ergonomic, not as "elegant", probably less expensive, simpler in concept, etc., I have a stack of 4 rear outlets and one of them has detented float.

I would appreciate comments.

 

[3RRL]

Reg,
Looks like a new item that is more "plug and play" indeed.

Instead of disconnecting one of your loader valve functions, just mount that unit, and feed it from where the loader valve gets it's input flow. In other words, disconnect the "IN" on the loader valve and connect it to the "IN" on your new solenoid valve. Then connect a hose from the "OUT" of your new solenoid valve to the "IN" of the loader valve. That puts the solenoid valve in play ALL the time, and you don't need to disconnect the loader valve to use it.

Run hoses from your new solenoid valve to your new grapple cylinder.
Note that I am not certain that the electric over hydraulic solenoid valve can operate a Post Hole Digger with a hydraulic motor. I'm certain it would work, but not certain for how long.

Why....??There might be something about the duty cycle of the electronics on it?? Operating a grapple is usually a momentary thing...for a few seconds at a time ... to open or close the grapple. The solenoid valve is not constantly under power for a long time like a hydraulic PHD would (might) be. You should check in that first.
Rob-

 

[Reg]

Reg,
Looks like a new item that is more "plug and play" indeed.

Instead of disconnecting one of your loader valve functions, just mount that unit, and feed it from where the loader valve gets it's input flow. In other words, disconnect the "IN" on the loader valve and connect it to the "IN" on your new solenoid valve. Then connect a hose from the "OUT" of your new solenoid valve to the "IN" of the loader valve. That puts the solenoid valve in play ALL the time, and you don't need to disconnect the loader valve to use it.

Run hoses from your new solenoid valve to your new grapple cylinder.
Note that I am not certain that the electric over hydraulic solenoid valve can operate a Post Hole Digger with a hydraulic motor. I'm certain it would work, but not certain for how long.

Why....??There might be something about the duty cycle of the electronics on it?? Operating a grapple is usually a momentary thing...for a few seconds at a time ... to open or close the grapple. The solenoid valve is not constantly under power for a long time like a hydraulic PHD would (might) be. You should check in that first.
Rob-

Thanks,
Good point about the solenoid duty cycle, I think it draws about 3 amps.
It shouldn't ALL get dissipated as heat, but 40 Watts is a worst case that I should probably consider and a several/many minutes post hole may be too much.

I will have to get my hands on the diverter to see exactly where/how to mount it.
I'm not sure (yet) that before the loader valve block is any different than after it - - OK, now I am sure, just went out there to look.
The valve block just has "pressure in", "power beyond" and "return to tank", so if I spliced into the "pressure in" it would divert pressure from FEL raise/lower when activated - which could still be OK, though doesn't "seem" the right way to do it.

Thanks again,

\R
Maybe long hoses from the rear BECAUSE OF the probable PHD... maybe, still procrastinating