Anybody have/put a Thumb on a Cat416C ExtendaBackhoe?

[ddiiggy]

I have never USED a thumb, but it looks like is would be useful in the right situations.
I tried looking for 416 pictures but they were mostly sale pictures and I didn't find pictures that focused on the thumb.


I was presented with this mechanical thumb and asked to see if it could be put on this backhoe.



It is ~36 inches from the hinge pin on the bucket to the end of the teeth and it is ~36" from the hinge on the thumb to the end of the fingers.
There is at least 18" between the hinges with the extend part fully in.
The thumb will not work with the dipper extended. I guess that is OK.
I don't think I can attach the thumb to the extender part, then there is nowhere for the brace arm.



The thumb unit doesn't look like it will fit on there real easy.
Is there any way to just bolt it on or clamp it somehow?

I may have to cut it apart and mount the hinge separate from the brace brackets.
The brace bracket end will fit between the edges of the dipper frame.
The Hinge section is wide enough that it would need to fit on top of the edges of the frame.
I would need to look out for how to get to the bolts that hold in the wear strips in the end of the dipper.
I may have to mount the hinge above the bottom angled portion of the dipper.

Can I weld the bottom hinge part onto the dipper arm?
Does it have a lot of stress on this or would a few welds hold it on?


This scabbed together picture looks like the thumb would be an awful far distance above the bucket.


Anybody? Suggestions? Pictures?

 

[Catback]

I can tell you you do not want to fasten it to the extension. A better way to tell if the thumb is appropriately sized is to curl the bucket up. This thumb looks like it adjusts out to almost 90'. Finally, yes it does need to be secure. If you're only picking up straw that's one thing. Pick up a 20" log and it's pretty hard to finesse the hoe so it doesn't exert "too much pressure" (because of substandard installation).

I have seen them clamped. You are mostly likely talking custom work for your app...like 3/8" plate and 1/2" grade 8 bolts.

Looks like it would work. I would just install according to manufacturer's spec.s, and/or lay a good bead about most of the perimeter.

Others will chime in with their experiences.

 

[El Hombre]

Clamp it. Position it so the hinge pin is opposite the curling link for the bucket. When you use it, don't see how hard you can force the bucket into the thumb. You just need a little pressure and then have the control valve hold the bucket in position.

Put the boom down and parallel to the ground, then you won't need 2 people to hold it in place. Try moving it up and down from the starting point opposite the link pin, you might find a sweet spot a little higher or lower. I copied the Amulet Hoe clamp for my hoe. It uses the two bucket pins and is a slick installation.

 

[wrc]

I noticed your stick has auxiliary lines on it. If they are two way hydros instead of hammer only there is a thumb that can use your hydros instead of being fixed that attaches with the main pin from the bucket. No welding or bolting on your boom at all simply change buckets and the thumb is gone. I have ran one like that before and they are great because the tip of the thumb is always the same lenght as the teeth on the bucket. Never too long or two short. Don't know if you have seen them or not. Google "main pin thumb " hope that helps

 

[ddiiggy]

I found these pictures somewhere. It looks like the thumb I have is do-able.




This looks nice: Probably make it even more of a pain to change buckets.



They say you can pin it out of the way if you don't want to be using it.
I don't see how you would do that easily.

I still think it would be BEST if the thumb had its own active hydraulics but I haven't see any way that works with the extend-a-hoe.



The auxiliary hoses on my boom are just Teed off from the extend-a-hoe hydraulics.
Put a pin in the extender and you can get hydraulic pressure to whatever else you have plugged in.

 

[El Hombre]

I found these pictures somewhere. It looks like the thumb I have is do-able.
View attachment 116828



This looks nice: Probably make it even more of a pain to change buckets.
View attachment 116829
View attachment 116830

They say you can pin it out of the way if you don't want to be using it.
I don't see how you would do that easily.

I still think it would be BEST if the thumb had its own active hydraulics but I haven't see any way that works with the extend-a-hoe.



The auxiliary hoses on my boom are just Teed off from the extend-a-hoe hydraulics.
Put a pin in the extender and you can get hydraulic pressure to whatever else you have plugged in.

The Hoe Clamp was the only thumb that works on your extend a hoe or my Dig-More; at least when I was researching it in 2000. It works, don't need to mess around with hydraulics, which is nice. My neighbor has a Deere with the female part of the boom sliding over the male. He has hydraulics on that; but it was $4k by the time he bought all the pieces and had them installed. It is a PITA to switch buckets, two people that know what they're doing, one to install pins and one to move the boom until the holes line up, makes it easier. By yourself, it's 15 minutes of fooling around.

There is another hole on the thumb that you pull the pin, push the thumb up against the boom, and reinstall the pin in the other hole. It's out of the way when you do that.