Started my first grapple project

[Keddowes]

The grapple end pieces came from the eBay auction today!

I mocked up my idea for a grapple to be attached to my Kubota L35 FEL, here are a couple of pics.





Material I plan on using.

Plasma cut 3/8" steel end pieces with 1" pin slots welded in.
4 scrifire from my box grader
Square and round tubing to weld between end pieces
Solid round steel through the hole of the scrifires welded on both sides
1" zerk fitted pins attached to bucket brackets - to be fabricated
1 hydraulic cylinder in the center of bucket
Quick connect hydraulic lines
3rd function hydraulic.



Question I have?

Should the teeth close inside the bucket or clamp down on the outer edge of the skid plate.

What would be a good separation of the teeth to get the widest grapple, yet strong enough for picking up large trees. ( want to prevent twisting of the grapple over time)

How do I figure out if I should use one or two hydraulic cylinders., where to place them? ( was thinking one in the center, 3 x whatever)

Already have a 2" receiver hitch welded to bucket for moving trailers around, thought I might fabricate the bracket for the hydraulic cylinder to slide into the receiver so that I could remove the grapple by taking out the two 1" pins and slide out the cylinder connection.
Here's a pic of my 2" receiver on the bucket.





Any help would be greatly appreciated.
Wish me luck, for I'm a computer guy and gentlemen farmer.
Kevin

 

[Keddowes]

A little better picture

 

[grsthegreat]

I made a similar thing for my old JD870...very similar in fact. But the round rods on mine never held up to the stress that the hydraulic cylinder put out. They kept bending. I fiddled with it some more, then gave up. I took the 8" cylinder and installed it on the snowblower rotator instead.

Most grapples i see are made of really thick steel plate. I hope this works out for you....and have fun making it.

 

[Kendrick]

just a humble opinion from an eyeballer... that hitch mount isnt tied in to the bucket secure enough to put a cilinder on. I would use a 3 point cat 1 pin for each side to attach to the bucket. 1 or 1/2" plate for those pins to tie in to. beef up the top edge and tie it in to the uprights your putting the pin through. at worst you could make 2 holes in the plate so that the jaws could either be outside or inside. since you dont have an open sided bucket that may not matter though. trees would be aginst the sidewall and the graple unless they were shorter then the bucket

 

[grsthegreat]

just a humble opinion from an eyeballer... that hitch mount isnt tied in to the bucket secure enough to put a cilinder on. I would use a 3 point cat 1 pin for each side to attach to the bucket. 1 or 1/2" plate for those pins to tie in to. beef up the top edge and tie it in to the uprights your putting the pin through. at worst you could make 2 holes in the plate so that the jaws could either be outside or inside. since you dont have an open sided bucket that may not matter though. trees would be aginst the sidewall and the graple unless they were shorter then the bucket

how hard is it to operate your backhoe with the cab tractor..... seems like it wouldnt work too well.

 

[Keddowes]

Thanks for the inputs,

Here's an updated photo on what I plan on doing via the input received. Please feel free to advise.






As for the cylinder connected to bucket. If I add the three point connection won't I loose the ability to use my hitches for moving trailers?

 

[EMB5530]

I think you are on the right track and I love the Idea of scarifier blades for the grapple teeth:thumbsup:
I never would have thought of it. I was thinkin about making a grapple eventually and I was going to go through all the work of cutting out patterns w/ a torch. What a time saver let me know how they work.
again thats awsome what a time saver

good luck

 

[J_J]

Here is something I made several years ago, using scarifier blades.

 

[Keddowes]

J-J
thanks for the pic, I have enjoyed your posts with others and glad your aware of my project for I'm sure I will have more question to come.

With my L35 hydraulic system I believe I have a 11 gpm system, what suggestion would you have on the size cylinder I should use? This tractor is very powerful for it's size and I have moved very large trees, I want to make sure I can hold and pick up large trees to cut and split.

Thanks

Kevin

 

[Keddowes]

J-J

Looking at your picture again, I see you welded tabs to the square stock and then bolted the scarifier to it through the holes already there., I know this is to allow pivoting but would I be better off doing something similar or will the butt joint welding be strong enough?

 

[J_J]

I would use square tubing or round tubing. That was a quick project. A root rake and grapple in one.

Just about any cyl will work and it might be to fast. You get more power with a larger cyl, and if I know the angle, I can compute the force. You could also add a needle valve to slow it down.

Are you going to use a diverter valve for the grapple, using the curl hyd? A switch on the joystick lever will switch between the two operations.

Yes, I have a tab for each scarifier, with grade 8 bolts.

 

[Keddowes]

Update on my grapple project attached are some new pictures of where I'm at.
I need help on the hydraulic location
I was thinking of mounting the hydraulic cylinder on the back side of the bucket and using a pivot arm on top of the grapple. How do I figure out what cylinder size to use and how much power it would generate. Also if I weld a bar on the top to a pivot pin to the back of the bucket will that be too weak or will it be strong enough. So many questions just don't know where to begin with the cylinder issue. Thanks in advance for all your help

 

[Keddowes]

Here is a picture of 1 of my welds thanks to my neighbor who is a welder who is also my teacher. Only going to show my best weld not going to show you the bubble gum welds.

 

[J_J]

Most people who build their grapples seem to put their cyl on the top of the grapple. A lot of the brand names put their cyl on the back of the grapple and connect it to an extension to two of the grapple arms. If you are thinking on the back sidw idea, use two cyl.

The force is calculated by the geometry of the cyl to the pivot pin and the length of the grapple teeth.

A 2 in cyl with 1 in rod, and 2500 psi will push at a force of 7854 lbs with a straight on push. If you are pushing on a 5 in leg, then you have the same force on the other side of the leg at 5 in, but at 10 in on the grapple side, , you have less force,and at 20 in you have even less force, but still enough to operate the grapple and hold things in place.

I think this is correct. Someone will correct me if I am wrong.

5 in on grapple side of pivot, the force is 7485 lbs
10------------------------------------------3742 lbs
15------------------------------------------2495 lbs
20------------------------------------------1871 lbs

 

[Keddowes]

Had a chance to work with a skid steer with a grapple
I'm now worried about my grapple not being strong enough need to beef it up some how.

 

[ak9]

Here are some pics of when i built my grapple ... I reinforced the entire top of the bucket w/a piece of 6" x 3" x 1/2" angle welded in & bolted & even with this angle I can still see a little flex when clamping the grapple .My set up weighs @ 250 lbs w/3" hyd cyl. The goemetry of the cylinder is important
you are doing good with your build . Grapples are so handy to have & well worth the time a effort to build one!!! hope these pics help

 

[Keddowes]

Need suggestions for hydraulic position ... Have valves And manifold 2 cylinders 2 1/2 X 8 X 1 1/2 - Retracted length 16 inches across tube rod 2 inches

Would like to use 2 cylinders 1 on either side of grapple possibly mount them to the existing bucket welds for tilt note in picture available room at the top of tilt bracket mounted to bucket. Here are some pictures of the grapple project to date.

 

[nybirdman]

Nice job on the build,why do you need two cylinders?I would think they would be fighting each other (with a one piece grapple) .I don't think you need two for strengh or power.

 

[Keddowes]

I was told the manifold will help with the hydraulics from competing. Going with 2 cylinders my thought is I will prevent racking or twisting.

 

[Keddowes]

I was told when mounting cylinders on the rear of the bucket two would be better