Bmg Clamshell Idea

[lumberjack]

I'm just designing at the moment, but I'd like to put it on the trailer. Right now I'm going back and adding thicknesses so I can get an idea of the weight of the segments.

The swing is still undecided, but a chain drive is high on the list.

 

[arborworks1]

Cool deal. Don't overbuild it and make the trailer to heavy.

LEt me know how that works, I would like to put a loader on a Nqr Isuzu. A mini Grapple truck if you will.

 

[SkwerI]

Maybe you could look at the hydraulic/ chain drive used for the chipper chute swing on some of the big chippers. Idunno, just tossing out an idea.

 

[arborworks1]

A shaft going down to a Large turntable gear turned by a hydro motor with gear on it would work also and be less hassle than chain. Make the mount for the hydro motor adjustable for wear on gears.

Chain drive is most likely cheaper to produce though.

 

[lumberjack]

Less hassle than chain? Here's the idea I was thinking about.

If I could get a slew bearing, that'd be tits. Finding a place online that shows the price has proven difficult.

The outrigger sub frame (inverted T in the above picture) without the outriggers is looking like 305lbs.

 

[arborworks1]

I had a different Idea of the chain drive. Most of those units I have looked at have been around 1500 to 1900 pounds, the whole deal.

 

[lumberjack]

Yeah, same here. Mine will most likely be heavier due to engineering deficiencies and using a lower tensile steel.

The outriggers w/o pads are presently 96lbs a piece. That's 500lbs combined in it's current state.


ETA, a rough guess on the weight of just the framework is around 1066lbs. Not nearly as bad as I thought, so now I can go back and add some beef back.

 

[lumberjack]

1597.56lbs.

Those holes add up to 413.89lbs of weight reduction. If I really decided to go that route I'd make them triangles so the pieces removed could be used for gussets.

 

[MasterBlaster]

How much do the holes weaken it?

 

[PCTREE]

Hey Carl if I were doing what you are thinking about I would probably look into picking up a used boom. Steel is high right now. I saw a prentice loader still mounted on a truck frame with rear axle and flatbed, cab cut off, on ebay go for $800. Somit ta thunk on

 

[lumberjack]

Holes that aggressive in the main boom reduce the strength. How much I haven't calculated yet.

The holes in the outrigger sub frame's cross member are about right to not reduce strenght significantly. They still reduce the weight from 586.92lbs to 462.10lbs.

PCTree, Prentice's weigh about 8klbs sitting on a pallet. Not very friendly for mounting on the front of a dump trailer/back of a 1 ton

 

[SkwerI]

Carl, you might take a look at the various Blue Ox models for ideas. They have been working on and refining this idea for a long time.

 

[lumberjack]

Good idea, Brian. I already see something to try.

I considered getting the slew the same way a chipper's chute does. 2 large thick plates connected with a large bolt, grease inbetween.

 

[sotc]

maybe teflon inbetween like a 5th wheel hitch

 

[lumberjack]

A teflon disk? Interesting idea, just like a slider puck in extending booms.

 

[darkstar]

Carl you might need to get onto design and make a fortune.
How did you pack so much in at 22 years old ?
Amazing

 

[Thor's Hammer]

some info for you Carl, european loader technology is quite advanced-
http://store.nyce.se/main.asp?SID=D31B0C5C03B6430BB59D856470C3BA6F&DepartmentCode=91

http://www.farmiforest.fi/index.php/Product-main-pages/Cranes-profiline.html

 

[lumberjack]

Thanks, Ed.

1432.87lbs

If you look closely you can see the .5" PFTE puck. The square post is 8"x8" and is sitting on a 12" circle. The through hole is 2", and the top plate (goes between the bolt head and the top of the top 12" steel disk) is 7" to fit inside the 8x8 tube. It also has its .5"PFTE puck.

With 1090lbs hanging where the grapple bolts on, and the arm fully extended, the COG (when looking from the side, excluding height) is about where the dipper arm pivots on the main arm.

That's roughly 109.5", or 9.125'. That means the weight of the loader + 1090lbs full out would put a moment load on the trailer's frame of23.3k ft/lbs, which isn't terrible. The same load puts about 48klbs of tension on the bolt that holds the slew joint together. I had in mind for that bolt to be a 1.5" bolt, with a .25" bushing. A 1.5" G8 fine thread bolt's tensile proof load is nearly 190klbs.

 

[JIML]

For the moneys, I would look for a used truck crane with a knuckle to start with. A friend of mine just bought a truck with a 22 foot one on it. Only downside is it is a little slow for slinging brush but would work fine for loading logs onto a small trailer.

 

[lumberjack]

I've been looking at those for years. Like you said, they are slower and they aren't nearly as heavy duty. Also, since I haul my brush unchipped, loading brush is kinda important.

Furthermore, with little extra planning it can double as a backhoe.

I'll try to work up a rough materials price tonight. I designed it for S&G.

 

[arborworks1]

Bad idea in the backhoe, I broke a peterson turntable like that. Trying to rip a small blowover out of the ground.

I like the design though, looking good. As well the weight is staying down nicely too.

Can you fabricate all the pieces or are you having to outsource some?

 

[lumberjack]

About $1800 delivered for what you see in the pics, including the PTFE. The price for the metal was from www.metalsonline.com. They're normally higher than local.

 

[Al Smith]

I Much like the prentice grapples. I have seen extensions that turn the prentice grapples into debris grapples,clamshells if you will.

Has anyone else Fabbed up something similar.

I just paid attention to this thread ,must have over looked it .

That radius bend on that grapple could easily be made from a big segment of a large pipe . You have to find a scrap yard that has some .I've made several dozer blades by simply cutting out a section of pipe to get the curvature . Just find some with about a 1/4" wall thickness and attack it with a cutting torch ,a 16-20 inch pipe should do the trick if you can find any .

They make big pipe with fairly thin wall sections. The trick is finding some after the extremely high price of scrap iron the last year .

 

[JIML]

Steel must be really expensive. For 1800 i could get enough to build 5 of them. I buy my metals from EMJ. You may have one local not sure.

Be a fun project. Hydraulics will be the expensive part.


Wonder what a large thrust bearing would cost for the turntable?
I don't see the PFTE holding up long. Not sure if you are shooting for 360 degree rotation or not. If not you could do it differently and have it be stronger... lemme draw something.

 

[JIML]

Something like this, Could use 2 pillow block bearings, but I piece of 3/4" plate with a 4 bolt flange bearing would be alot stronger. You could get 180 out of it, probably a little more.

4 bolt flange bearing

pillow block bearing