Loader New Grapple Build! Let me know what you think

[slharman1]

Ok,

I hope I am posting in the right location.

So i finally got my design moving along and I was thinking you guys could help make any necessary changes while it's still in the design stage.
Any and all comments would be appreciated.

The grapple will be 50" long and have an opening of right at 40", I have my tines spaced at right at 9" to help keep the weight down.

I am putting it my Mahindra 2538HST.

Any advice is appreciated.

Thanks

 

[slharman1]

Here's one with the jaws open.

 

[slharman1]

Here's one with the jaws open.
View attachment 499150
View attachment 499152

 

[slharman1]

I need some help with the bushing and shafts.
Does anyone have a line on getting those near Houston?
Found the cylinder at Suplus Center.
I am trying to decide between WR Long and Construction Attachments "one touch" kit.
Or just build my own from scratch (with a little help from my friends here on TBN :thumbsup
So any suggestions would be nice.
Thanks
Steve

 

[RNeumann]

The 3rd function can be made. Hyvair makes the valves and Scorpion makes the nice joystick.
If you are going through the trouble to build a grapple the 3rd function will be easy!

Isn't the bushing just some hardened steel for the "eye" and a hardened pin (most are hardened? Seems you could cut the holes in a few pieces of 3/8" and weld them on either side of the grapple tabs shown. Just have the tabs capture both sides of the lid.

 

[slharman1]

The 3rd function can be made. Hyvair makes the valves and Scorpion makes the nice joystick.
If you are going through the trouble to build a grapple the 3rd function will be easy!

Isn't the bushing just some hardened steel for the "eye" and a hardened pin (most are hardened? Seems you could cut the holes in a few pieces of 3/8" and weld them on either side of the grapple tabs shown. Just have the tabs capture both sides of the lid.

I have been looking at the 3rd function kits and thinking to myself why spend that money when I can build the "kit" myself, especially since Hyvair is about 5 miles from my house.
Might even build my own handle since I don't know if I like the Scorpion handle - we'll see.

As far as the bushings, I will probably make them as well but I want Grease zerks in them. As you can tell by my model I haven't got the qucik attach plate or the cylinder mounts model yet but I am working on it.

I have been thinking about using the high tensile strength steel similar to what EA uses on their grapple. That might allow me to go to 5/16" on the steel and put the blades of the grapple closer together without sacrificing too much weight.

As it stands right now I am all in just under 300 lbs, which I like a lot.

Any other ideas?

 

[MossRoad]

For bushings and pins you can also use DOM tubing and hard bolts. Drill and tap the tubing for a grease zerk.

Here's a good source for metals on line. I've used them before. Pretty much anything you need at any size you need. :thumbsup:

Online Metal Store | Small Quantity Metal Orders | Metal Cutting, Sales & Shipping | Buy Steel, Aluminum, Copper, Brass, Stainless | Metal Product Guides at OnlineMetals.com

 

[jb1390]

Ok,

I hope I am posting in the right location.View attachment 499145

So i finally got my design moving along and I was thinking you guys could help make any necessary changes while it's still in the design stage.
Any and all comments would be appreciated.

The grapple will be 50" long and have an opening of right at 40", I have my tines spaced at right at 9" to help keep the weight down.

I am putting it my Mahindra 2538HST.

Any advice is appreciated.

Thanks

I have a couple thoughts.

1. Can you show the SS adapter on the back of the grapple? It appears there may be extra material on the lower corner that is not required for strength. It may be required for the height of the adapter however.
2. If you are cutting the holes for weight savings, I would consider making them a bit larger, or not bother with the holes. The current size shown will not result in significant weight savings.
3. Consider angling the back of the grapple further forward. Assuming your SS adapter on the tractor is vertical when rolled fully back, some additional angle might be helpful with getting material to fall back into the bucket. This, of course, will depend on your uses for it. For some purposes, this would be a disadvantage.
4. What thickness are your tines? I would seriously consider using Hardox vs mild steel, and using thinner tines. If you have never used Hardox, it is amazing stuff. The cost difference is probably worth the impressive weight savings you will see by going to thinner material. For reference, mild steel is around 50k psi yield strength, Hardox 450 is around 175k psi. You could go with 1/4" tines easily.
5. I would use larger pipe for the cross bracing. I think you will bend the smaller ones shown.
6. If you are using it for placing rocks in stone walls, it may be helpful to have the edge of the jaw closer to the edge of the bucket so you can lift and place using the corner of the bucket/jaw. For brush, this is insignificant.
7. For bushings, I like to use grade 8 lock washers along with a drilled hole in the material. They fit tight to the pin generally. I cut opposite the factory cut with a die grinder, almost all the way through so they lay flat. Then run a bead around the edge. Not replaceable obviously, but I doubt that's an issue for this application.
8. For third function, I have the WR long kit on mine. I like having the switch on the loader handle. Some people just run off the rear remote, it's a cheaper option if you don't mind the ergonomics.

What weight is your model currently? It looks similar to the model of the grapple I plan to build one of these days. My design is not quite as far along as yours is however. I need to flesh out the details. It is currently around 350 pounds for a 5 footer, with a clamp force of a few thousand pounds. Are you using Solidworks? Have you done any structural analysis on it?

 

[4570Man]

I didn't see where the op mentioned using a grapple to place the stones in a wall, but if that was the intended use I'd scrap it in favor of this design.

 

[slharman1]

Thanks for all the help!

MossRoad:
Thanks for the link to the Metal Store, I will check them out and see if I want to build my own bushing or by some.

jb1390:
I really appreciate all of the suggestions, here is some more information:

1. I haven't modeled the ss adapter yet but I will build it as well. The back of the grapple frame is approx 19 1/4" so I could move the bottom frame up a bit and round the corner or remove some more metal on the bottom of the tines - is this what you are referring to?

2. The holes are for weight savings, I will probably make them bigger, my tines are 3" tall, what size holes do you think I can get away with?

3. My tractor adapter plate is vertical when tilted all the way up. My design is titled at 80 degrees right now. Some of the grapples I looked at were tilted at 75 degrees. So I will do that. do you think that is sufficient?

4. My tines are currently 3/8" thick, I was planning on changing them to 3/8" and using Hardvox - didn't know the name but I was researching steel strength and found some stuff while at work, don't remember the name of it but it used for building excavator implements and such. If I use that do you think I can really get away with 1/4" instead of 5/16"?

5. I know is sounds lazy but I had the 1" pipe already modeled, I was planning on using 1" bar - do you think I should use a 2" pipe instead?

6.I will be using it to move logs, brush and debris, loading it in trailers or to the burn pile. In addition, I will be using it for help with stump removal. Right now the back side of the upper front tine is 1 3/8" from the leading edge of the lower tines. will this be ok for my use?

7. I will probably make my bushing with some DOM tubing like MossRoad suggested if the fit to the pin is tight, i think I want them removable but now I am questioning the necessity of that. I am not sure I need them removable now.

8. for third function I was planning on going over to Hyvair since they are about 5 min. from the house and see if I can talk them out of a valve. I would then either buy my loader handle or make that as well. I don't think I like the scorpion handle as much as the one from WR Long. still thinking about it.

I am using Solidworks but I only have about 9 months experience on it so I am not sure how to do the analysis - any help with that would be appreciated as well.
My model is 54" long and without the ss adapter on it I am right around 275 so I would like to take a little more weight out since I am putting it on a Mahindra 2538.
I can send you the model if you have solidworks 2016.

Thanks again for all the help!
Let me know what you think.
I will modify the model and upload again hopefully today.
slharman1