While I've published photos and description of the grapple hydraulics and of the power beyond remote valve installation probably the most difficult feat of the hydraulic thumb design has been getting the cylinder choice and design. Especially the John Deere 260B backhoe has the stylish curved or flared design mounting bracket. However this makes it difficult to find a cylinder that will clear the bracket. A simpler drop down reinforced bracket would have been better. I checked with the major manufacturers and the cylinder input ends are close to the cross bar therefore the line conflicts. Also the cross bar design has to be cut and turned 90 degrees to allow the lines to be on the side. Otherwise the boom would have had to been hollow on the underneath side or you would have lines dangling from the lower mounting. The side outlets were my choice and actually a "tang cylinder" 17" retracted was my choice but none available. I had the popular type thumb but it was designed for an adjustable square shaft. "why on earth they don't sell a cylinder or design for hydraulics is puzzling". While I did see TTWT model, the push button and the massive design just didn't appeal. I don't know if his was a Deere design or another manufacturer. What I did was altered a cross fit cylinder by cutting the rod off 1" and also changing the rear of the housing. I did make one mistake and cut into the housing but was able to weld the housing. The bracket end on the housing had to also be slightly lenghtened. But anyway I got it so suit and did a field test on it yesterday. I was totally shocked at it's performance. The spread of the opening was massive and pinch and lift fabulous. I tried everywhere to get a "tang cylinder" with a 17" retraction but there were none to be found. I've never heard of a hydraulic cylinder shortage in my life. One really needs the inlets to be more in center much like the design of the top link hydraulic cylinder but none of them had the proper lenght usages. But anyway there's a market for someone specifically designing the cylinder for the 260b backhoe and your favorite thumb. Oh by the way the thumb and inlet do not contact, slight grinding for clearance.
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