grapple hydraulic setup 1026r

[swick1]

I just got my bosch style diverter valve from surplus center and I'm getting ready to build a mount for it and hook up my hydraulic hoses this weekend or early next week. I'm building the grapple from a sheet of steel diamond plate I got for $60 at the scrap yard. Total cost for the project should be around $500. I'm going to take a few days to finalize the design and it could take a week to get my sheet on the laser cutter or plasma table.

I'll be asking questions and posting pictures as I go. This is my first hydraulic project so I'll go ahead and ask about hose connections first.

What do I use to seal the threads and how tight should I torque the hoses? (3/8 hose)

Is there anything wrong with using 90 degree fittings on my diverter valve? I think the flow is low enough I can get away with it.

 

[J_J]

You only need Teflon paste on the NPT fittings.

Use either 90 degree or 45 degree. No problem.

 

[swick1]

Thanks JJ

Here are the parts I have so far...

1. electrical quick disconnect for removing FEL easily. I will locate this by the hydraulic connectors under the floorboard.
[ame=http://www.amazon.com/ACCEL-74812-Weatherproof-Electrical-Connector/dp/B001HQEUKC/ref=sr_1_3?ie=UTF8&qid=1338477575&sr=8-3]Amazon.com: ACCEL DFI 74812 Weatherproof Electrical 2 Pin Connector: Automotive[/ame]

2. diverter valve and connector
Surplus Center - 12 VDC 13.2 GPM SAE 8 DOUBLE SELECTOR VALVE
Surplus Center - HIRSCHMANN CONNECTOR

3. quick disconnects for grapple
Surplus Center - 3/8" NPT QUICK COUPLER F/F S40-3

4. grapple cylinder (2" bore by 6" stroke)
Surplus Center - 2x6x1.125 DA HYD CYL LION 20LH06-112 3000 PSI

I used a tie rod cylinder because that's the same thing the toro dingo grapple uses which i'm copying my design from.

Here's the dingo grapple I took measurements from at the John Deere dealership: grapple pictures by backhoeworks - Photobucket

I have a lot of 25 joystick handles from ebay coming in. I'll part them out once I find out which one I want to use

I'm going to fabricate some brackets and get everything mounted then I think i'll haul the tractor to our local hydraulics shop to get all the fittings and hoses I need. I'm planning on zip tying my hoses to the hard lines that run down the loader arm and either buying or building a bracket to hold my quick disconnects. Any suggestions on how to hold the quick disconnects?

 

[swick1]

Here's my electrical diagram for the selector valve. I made this for my dad to do this weekend:

http://i1196.photobucket.com/albums/aa415/backhoeworks/grapple/elec.jpg?t=1338564491

 

[Zebrafive]

I would use bulkhead fittings to mount the quick couplers. Get the same type of threads as your couplers and hoses. You will need to make a bracket for the bulkhead fittings.

 

[ch47dpilot]

with a 3 amp draw probably don't need the relay and could just wire direct from switch to valve. I include two pics I saved from an old post that shows how one guy mounted his quick disconnects. The first is a good pic of the bracket, second is of the bracket mounted. Send some pics on how you mount the valve. I have the same valve and am trying to find a way of mounting it to the FEL on my Kubota L3400HST. I plan to tap into the lines were the rubber hose connects to the solid line. Can't figure a way to mount it without welding or drilling into FEL arms. Like to see what you come up with.

 

[murphy1244]

Here's my electrical diagram for the selector valve. I made this for my dad to do this weekend:

http://i1196.photobucket.com/albums/aa415/backhoeworks/grapple/elec.jpg?t=1338564491

Don't run the ground thru the relay. That wont work.

 

[swick1]

Thanks for the bulkhead fitting tip. I've done it before with lab tubing! Never thought about it for hydraulics!

 

[swick1]

Murphy, I can't see why it won't work. What am I missing?

 

[Zebrafive]

Here's my electrical diagram for the selector valve. I made this for my dad to do this weekend:

http://i1196.photobucket.com/albums/aa415/backhoeworks/grapple/elec.jpg?t=1338564491

NOT RIGHT!

12 volt positive should NOT go to the valve from the battery.
The valve needs a ground.
12 volt positive for the valve should come from the switched (normally open) terminal of the relay
The relay needs a 12 volt supply to the common terminal of the relay. It should be protected, fuse or circuit breaker. It can be direct from the battery or from a source only "hot" with the key ON. As long as circuit choosen will support the amp draw of the valve.

The relay has a coil. When current energises the coil the relay switches the power to the valve. You need to get 12 volts across the coil of the relay. There are several ways to do that. If you want it to only work with the key ON you need to find a 12 volt supply that is only "hot" with the key on. You can then send this 12 volts to your joystick switch, from the joystick switch to the relay coil. Then gound the other side of the coil.
OR you can send this 12 volt supply to the relay coil, then from the other side of the relay coil go to the joystick switch, then from the other side of the joystick switch go to ground. This way may take less wire.

 

[swick1]

I found out tonight that tractor supply doesn't have nearly enough fittings to plumb this project. They didn't even have 3/8 qc dust covers! I'm just going to have custom hoses made at the hydraulic shop in town. I didn't like all of the fittings it was going to take or the stock hose lengths. May as well do it right. I don't want leaks or ugliness. Any idea the difference in price between hard lines and hose?

 

[swick1]

NOT RIGHT!

12 volt positive should NOT go to the valve from the battery.
The valve needs a ground.
12 volt positive for the valve should come from the switched (normally open) terminal of the relay
The relay needs a 12 volt supply to the common terminal of the relay. It should be protected, fuse or circuit breaker. It can be direct from the battery or from a source only "hot" with the key ON. As long as circuit choosen will support the amp draw of the valve.

The relay has a coil. When current energises the coil the relay switches the power to the valve. You need to get 12 volts across the coil of the relay. There are several ways to do that. If you want it to only work with the key ON you need to find a 12 volt supply that is only "hot" with the key on. You can then send this 12 volts to your joystick switch, from the joystick switch to the relay coil. Then gound the other side of the coil.
OR you can send this 12 volt supply to the relay coil, then from the other side of the relay coil go to the joystick switch, then from the other side of the joystick switch go to ground. This way may take less wire.

If the ground terminal of the valve is floating it should work. Surplus center datasheet may be wrong. It only shows two terminals hooked up.

 

[dstig1]

You should also add a diode at the Bosch valve, as close as possible to the valve connector. When the coil opens, it feedback voltage that can cause damage. I don't know the specifics of it, but it has been told to me a few times over the years by different people, so I'm pretty confident in the info. My wiring harness from Fasse had a diode soldered into it at the connector to the diverter valve, from the factory, FYI...

 

[J_J]

Here is the reason for the diode.

When power is applied to the relay coil, a magnetic field is created and energy is stored in the coil. When power is removed, the magnetic field collapses causing a reverse voltage to be generated (it's called inductive kickback or back EMF). The back EMF can easily reach 200 volts. The diode will absorb the reverse voltage spike. This voltage, if not absorbed by the diode, will cause premature failure of switch contacts.

Flyback diode - Wikipedia, the free encyclopedia

Surge Suppression and Diodes Installation Tips

 

[swick1]

I agree with the diode suggestion. I will make it happen.

 

[swick1]

After 11 hours Cad work is done for the grapple bucket! I sent the nested parts drawing to the plasma cutter man. Next week may be bucket fab week!

 

[swick1]

Here are some pictures of my design. I added teeth between the two front tines so i could pick up firewood while facing it instead of being beside it.

 

[J_J]

Will the added teeth affect your root rake ability?

 

[swick1]

I'm not really sure how it will work. I assume it'll be like having a big ratchet rake on the front. I copied it from a toro dingo grapple I liked. I have a backhoe, so digging out roots isn't a huge priority for me. I mostly want to use this to clean up brush, trees, and construction debris.

 

[swick1]

I just got a call from the hydraulics shop after dropping off the tractor. They want $150/hr and think it will take 2-3 hours to make my hoses. I told them I didn't want the hoses installed yet, just made up and they wouldn't give me a price. I think that's a lot of money for what they are doing. I think i'm going to just buy stock hoses online, cut off one end of each hose, and use repair ends to plumb everything. Is this a bad idea?