Thumb Hydraulic thumb for BX23 BH

   / Hydraulic thumb for BX23 BH
  • Thread Starter
#81  
</font><font color="blue" class="small">( I have heard the same sentiments from manufacturer's when I asked about grapples or fork attachements for the BX FEL. It is an attitude I really can't quite understand. Maybe my attitude is getting bad but lately I have taken to saying " Yes - after almost 300 hours with my BX I am intimately familiar with what the FEL can and cannot lift - and that happens to be a lot more than I can lift using my back and leg muscles. If had wanted a bigger tractor I would have bought one - what I am looking to do is make this tractor more useful. A grapple on the BX bucket still makes the tractor more useful if I can hold something in the bucket I could not otherwise." /forums/images/graemlins/wink.gif .)</font>I tend to agree. I was just repeating what I was told by the grapple manu., I recently cleared a very large pile of stone and clay with the little BX. I picked up rocks I was sure it could not. You have to be careful and keep the load low until ready to dump but I was very impressed with it's lifting ability. I am not impressed with the bucket curl power. It should have had two cylinders but thats another story. Knowing me, we will build the grapple as I would mostly use it to load the stones we pick off the beach and put them into a dump trailer. It comes in handy to be able to "pick" the stones rather than push them to load them into the bucket.

</font><font color="blue" class="small">( The thumb looks excellent by the way)</font>Thank you.

</font><font color="blue" class="small">( - I would also be very interested in the list of parts that were used to do this. Who made the actual thumb assembly? Was that your fabricator? Do you think he would be interested in making any more? )</font>My fabricator built it all from scratch using just photos and my limited knowledge of what I thought we needed to do to the designs we had. I am putting together a parts list and yes he will build them if you want one.

From preliminary numbers we were putting together it looks like around $ 1,000. That would include the Kubota valve w/pressure relief valves (which is over $200 itself), lever and assembly (I think this around $20), cylinder (Just under $100), hoses, thumb itself welded together but not installed (unless you wanted to bring the tractor to him), fittings, brackets and all. Now there is some small fabrication involved on the housing and the painting was just a bonus for me as this guy can paint also.

The fabricating was to the housing of the assembly. New holes have to be drilled to move the valve body to the center and the top plate has to be cut down 3/4" on one side and have 3/4" added to the other. (We found this to be the easiest way to do it.) He may be able to order these and fabricate them as needed. So I guess it would depend on how much of it you wanted to do yourself. And there is some small cutting that needs to be done to repostion the stabilizer levers along with a bolt that has to be used to move the levers. None of it is all that hard just time consuming.
 
   / Hydraulic thumb for BX23 BH #82  
My guess is that the total weight is about 40 pounds. I believe that he has some made up and ready for shipping. As you could see from the picture, it works well and holds the load in the bucket.... Junk...
 
   / Hydraulic thumb for BX23 BH
  • Thread Starter
#83  
</font><font color="blue" class="small">( My guess is that the total weight is about 40 pounds. I believe that he has some made up and ready for shipping. As you could see from the picture, it works well and holds the load in the bucket.... Junk... )</font>Now that is a reasonable weight. The one I was looking at before was 130lbs. Significant difference.

Thanks
 
   / Hydraulic thumb for BX23 BH #84  
Junk what did that good looking grapple set you back?
 
   / Hydraulic thumb for BX23 BH #85  
Hey, NASDAQSAM, nice job on the thumb. I am designing my own thumb and I have a structural question for you: I see you are using the substantial BH90 hoe. Can you tell what the thickness of the end of the dipper stick wall is? My concern with my 7.5' hoe is that the walls are only 1/8" thick, which is generally what this size of hoe uses. The part of the thumb attached nearest the bucket will experience several thousand pounds of pull-out tension. I am concerned about distorting my dipperstick, so I will weld brackets along the sides of the dipper stick in this area. This is also why the thumb brackets must be welded, rather than bolted, as you have done.
 
   / Hydraulic thumb for BX23 BH
  • Thread Starter
#86  
Thank you,

We did not cut through the stick at any point to actually see what it is constructed of. However, the way it is built the two sides pass by the front and back plates and they looked like they were indeed 1/8". We did not weld across the stick as from my understanding is a no-no. We wleded both sides. So, I you should be in about the same boat we were in. There was no distortion what so ever of the stick.

Tomorrow I am going to be able to give it real test as I have about 20 medium to large stones to pick out of a field. I will try to get some pictures.
 
   / Hydraulic thumb for BX23 BH #87  
Could you please show a picture of these welds for better understanding...... Thanks.... Junk..
 
   / Hydraulic thumb for BX23 BH
  • Thread Starter
#89  
Just a quick update for those interested.

Used the Thumb this weekend for a little more than just playing around. No pictures, sorry. Brought the digital but forgot to charge it. /forums/images/graemlins/blush.gif

Anyway, Several issues we need to iron out.

-Still waiting for the factory hoses I ordered to reroute them. They are too tight as set-up now so some work needs to be done there.

-We also need to add a stopper for when the thumb is retracted as under some circumstances you can push the thumb past the sweet spot and it locks up. Making the cylinder work against itself and pull it towards the stick. A quick stopper will solve this issue.

-Last observation. We either need to find a different cylinder with the ports on the side or build a shield to protect them. Again, in certain situations I can see where an odd shaped item could get caught and break off the elbow. I am going to look for a cylinder but will more than likely just have a shield built. OR maybe both.

Just some things to watch for as you build your thumb. Hope this helps.

Stay tuned.......
 
   / Hydraulic thumb for BX23 BH #90  
Guys,
there are a couple of recent threads going about the same subject.
This inquiry is aimed at no one in particular.
I just grabbed the most recent post out of convienience.

I have a question concerning the actual use of a hydraulic thumb.
I understand the thumb cylinder is used to actuate and retract the thumb. What happens when the "grip" is closed? Will the bucket curl cylinder fight the thumb cylinder and force the fluid against and past the valve spool? How is this compensated for? Doesn't this have a profoundly diminishing effect on the "grip" pressure.
Answers please.

Shouldn't the thumb travel "over center" into a mechanically locking position instead of relying solely on the cylinder pressure applied?
Answers please.

So, from the above you can see that I'm a bit of a fibber, I did say I had A question. Sorry. I was thinking about this during the ride in and I'm not sure the traffic lights I crossed were actually green, and I ramble.

Thanks for your patience and answers,
Martin
 
 

Tractor & Equipment Auctions

2005 Toyota Tundra Limited Crew Cab Pickup Truck (A51692)
2005 Toyota Tundra...
2002 Western Star 4900 T/A Galbreath Rolloff Truck (A51692)
2002 Western Star...
2013 Nissan Rogue SUV (A51694)
2013 Nissan Rogue...
2017 Bayliner VR5 21ft Bowrider Boat with 29ft T/A Boat Trailer (A51694)
2017 Bayliner VR5...
Ryobi Sliding Compound Miter Saw (A51573)
Ryobi Sliding...
NEW 2024 LOAD TRAIL 83IN X 14FT Tandem Axle Dump Low-pro Trailer (A53472)
NEW 2024 LOAD...
 
Top