Thumb addition causing dipper stick damage?

[UWAdventurer]

Has anyone had issues with dipper stick damage after adding a thumb to their back hoe? I am looking at a mechanical thumb with the possibility of hydraulic conversion later. I wouldn't think it would be a problem because Woods offers a thumb option, but my dealer says their may not be enough strength in the arm.

 

[Adiredneck]

No problems with mine.

 

[dfkrug]

I wouldn't think it would be a problem because Woods offers a thumb option, but my dealer says their may not be enough strength in the arm.

Woods offers thumbs for the Groundbreaker X series, but not the older
7500, AFAIK.

The 7500 dipper stick has very thin walls and it is not designed for
forces directly acting on it. The 2 end pivots use welded-in DOM tubing
to add strength at these points. If you decide to weld a custom
thumb on the dipper (or one you buy off the shelf), you must strengthen
the dipper at any connection point. For my thumbs, I weld on reinforcement
plates and have no problems (fixed or hydraulic).

There is a bolt-on thumb out there that has been known to slip under force,
and even distort the dipper.

 

[UWAdventurer]

According to the manual my back hoe is a BH7500. It does not mention "Groundbreaker" so I am assuming it will need reinforcement.

dfkrug: Could you be more specific how large and where you placed the reinforcement? I don't have any experience with this type of application, so I am looking for any help and expertise I can get.

I was looking at a bolt on mechanical thumb from Hound dog BT75-SH.

Thanks all.

 

[dfkrug]

Here is a thread where I deal with the structural issues:

http://www.tractorbynet.com/forums/build-yourself/125912-custom-hydraulic-backhoe-thumb.html

I am not a fan of the bolt-on thumbs. The forces are large, and the
the attachment should be securely welded, IMO.

That said, you CAN install a thumb on the old 7500, if you do it right.
You will wonder why you waited....

 

[UWAdventurer]

I checked my back hoe this morning and it is a Woods Groundbreaker BH7500, with that being said is additional reinforcement necessary for the addition of a bolt on mechanical thumb? I am assuming the Groundbreakers are built stronger? I am going to go with a bolt on because I have some limited use for the thumb and I don't think I can justify the cost for the weld on and hydraulics.

Nice write up dfkrug.

Thanks all.

 

[dfkrug]

I am assuming the Groundbreakers are built stronger?

Stronger than what?

After the "Du-Al", Woods made the 750, then the 7500, then the BH80-X.
All were about the same size (7.5 dig depth) and weight.

Looking closely at the curvy-boom series, I can not see if the BH80-X
uses thicker dippers than previous units, but, based on the fact that they
don't really weigh significantly more, I doubt it. Most hoe attachments
of this class are going to have thin dipper walls, since weight is a concern
and it does not need to be very thick as long as you don't push on
them in the wrong places.

As for my thumb projects, thanks. Hydraulic is WAY more work and cost
vs. a simple mechanical thumb. It says something that Woods welds
an upper attachment to their BH80-X dippers, whether you opt for that
very expensive option or not.

 

[nickel plate]

I checked my back hoe this morning and it is a Woods Groundbreaker BH7500, with that being said is additional reinforcement necessary for the addition of a bolt on mechanical thumb? I am assuming the Groundbreakers are built stronger? I am going to go with a bolt on because I have some limited use for the thumb and I don't think I can justify the cost for the weld on and hydraulics.

Nice write up dfkrug.

Thanks all.

Woods only builds thumbs for the later version of the Groundbreaker, the Groundbreaker "X" series, BH90-X and more recently the BH80-X series. Although your BH7500 is a fine backhoe, it is not in that grouping that offers a mechanical or hydraulic thumb built by Woods.

 

[RFB]

Here is a post on the general idea

http://www.tractorbynet.com/forums/build-yourself/166787-backhoe-thumb-weld-bolt-3.html#post1925226

 

[jakell2010]

I've seen some pics on here of twisted booms,,,,you can use them, but not abuse. Them

 

[UWAdventurer]

I was ready to order a thumb, I am going to investigate more now thanks to you guys. Might contact Woods and see if they can give me any info on making my dipper stick, etc. stronger.

Thanks for all the info.

 

[MG1867]

I just installed a Bro Tek thumb. The instructions say to install loosely and slide up the dipper arm till it stops. I don't see how it could slip any more because of the taper. I have moved a few logs so far but will post later and let you all know how it holds up. I would assume there is a limit to what you can pick up with one of these and like anything if you over work it something breaks. Good info though. :thumbsup:

 

[UWAdventurer]

Woods says they do not recommend installing a thumb on my back hoe. I am really bummed out. Had plans for that baby.

I am still tempted to try it.

Anyone else have the Woods BH7500 Groundbreaker with a thumb installed? Any detrimental effects?

 

[nickel plate]

Give Michigan Iron and Equipment a toll free call 1-855) 265-4590. They are one of our sponsors and build their own thumb kits that either clamp on for break out force 3000lbs and 4000lbs or weld on for 4000lbs to 10000lbs BOF. In both cases, the mechanical kits can be upgraded later on to hydraulic. They have charts and prices on the website-look at the Kioti site on our forum index page and just click on MIE's advertisement and off you go!
I have purchased a backhoe ripper tooth and a FEL bucket grapple custom built by them and am very pleased with both.

 

[dfkrug]

Anyone else have the Woods BH7500 Groundbreaker with a thumb installed? Any detrimental effects?

Here is my thumb kit welded onto an actual blue Woods 7500 hoe. Tho the
Woods unit is not quite as stout as my 7500 clone hoe (Prairie Dog 7.5),
the owner has reported no problems. The most important element is
the forward brackets that are welded all the way around the end of the
dipper. Not just to the inner surface.

 

[UWAdventurer]

Thanks for the photo and info dfkrug.

Nickle plate, I was Emailing back and forth with MIE and was thinking about the bolt on unit for my back hoe. You guys have me thinking about the weld on though.

Does the ripper tooth work well? I am removing stumps and having problems with roots.

Glad to know MIE is good to work with, I didn't realize they were a sponsor. I will try to give them a call instead of an Email.

Thanks again guys.

 

[SpringHollow]

I have a thumb that slides up and down the dipper to adjust for size, binds to stay in place when you apply pressure. The design works real well but I did put a small dip into the dipper when prying on a large log.

Ken

 

[AMR]

I have worked my Brot-Tek thumb pretty hard for 3 years now

I put 12 hours on my BH this weekend moving rocks up to about 2' long by 2.5' wide 8" deep, stumps, general brush and anything else that got near my BH

This is a glamour shot of the thumb, I have had zero issues

My only complaint is that I can't completely roll my bucket back but it only stops about an inch short, I can deal with that for the utility

Believe me, had they had a hydraulic option I would have bought it, this is the next best thing for me and relatively cheap

 

[UWAdventurer]

AMR, what back hoe do you have?

 

[AMR]

UWAdventurer, I have the Kubota BH75A on my B3030

I actually took a good look at it again last night in the garage and it looks to me like the way the Bro-Tek thumb fits and works will not be an issue, the dipper looks just fine

As I stated before I have done what was needed to move some really big rocks, the only issue is that I can't roll the bucket back entirely it stops with about 1" of cylinder left