I've used both. In my opionion the grabble sucks on machines that are larger than 65 to 70 thousand lbs. The grapples stationary side is to thick and hard to pick up smaller objects. Mostly, I don't like it because your visibility is limited when picking things up, you can't see behind the stationary side of the grapple. My setup is a rake with a thumb, it serves a similar purpose like the grapple. The ability to grab a lot of stuff at one time is limited with a standard bucket. Hope this helps.
Last edited by CM1995; 11-05-2009 at 05:19 PM. Reason: disquised profanity
I have used both grapples and thumbs, and in my opinion, if you have a grapple, you are wrecking, handling large/bulk material, or loading trucks. they work best on larger machines. and with an experienced enough operator, you can in fact do some fine picking. at the last company I worked for, buckets/thumbs were unheard of. we had some darn good operators who could pick fine wire with a grapple. the standard 3-2 tooth box grapple can't be beat for heavy demolition work, there are limited parts to break (I.E. Keepers, teeth, cylinders, hoses)
up until about 2 months ago, i had never used a hydraulic thumb, it does have it's place, however I don't care for the fact that it's hard to hold your scraper beam tight, because you have 2 cylinders one always wants to push the other one, (generally the bucket cyl pushes the thumb cyl.) although I love loading trucks using a hydraulic thumb over a grapple, because you can fold it up at any time and get it right out of the way. I also like the thumb/bucket combo for doing brick demo, because it's much easier to scoop brick than it is to pinch it.
I have also learned the value of a bucket's ability to do fine picking...though I still run my thumb like a stiff arm grapple most of the time: keep the thumb fixed, put it behind what you're picking and bring the bucket to meet the thumb.
finally I feel that a grapple has more of a use when picking from a concrete slab, but with a bucket you need to be able to actually get under the material a little in order to get a good grip.
so. both have their place, and a good operator can make efficient use of either one he is given. it really all depends on the particular situation. unfortunately, most contractors pick one and stick with it, I haven't seen too many that use both thumbs and grapples
Last edited by Demoguy324; 10-28-2007 at 06:15 PM.
when im doing a lot of fine picking, or something using the thumb a lot i generally keep the thumb out and bring the bucket to the thumb. For one, you have more control, with a thumb switch its either open or close at full speed, and two is its just faster. I can pick up a glass bottle with the thumb, while on the other hand ive seen guys that couldnt pick up a concrete catch basin riser with the thumb. they dont think to gently curl the bucket instead of slaming the thumb closed
I was able to pick up a piece of sidewalk and with it pinched between the bucket and thumb, rotate the whole thing until it was standing up straight to be buried, all without exerting excess force against the bucket or thumb cylinders.
2001 Cat 420D with a bunch of goodies
1977 Gmc 6500 dump with 10ft plow
A thumb has its place, but I prefer the grapple for demo. The thumb is nice on a small machine or if your going to use it occasionally to move something. Like said earlier, if your a good operator you can pick a fine piece of copper out of a pile.
I like the hydraulic thumbs over the fixed. You dont have to do as much tracking/ moving the machine if its hydraulic. Just make sure that thumb cylinder is weaker than the one on the bucket is, or you will be buying a new thumb cylinder. On our daewoo the dealer had to replace the thumb cylinder twice because it kept bending because they did not set the presure release right.
To see our equipment in action:
For demo purposes def go with the grapple. the thumbs are nice but are so easy to abuse since your point of contact is so much farther out like at the end of the thumb were the bucket teeth meet. a grapple on the other hand picks up most things in the palm area instead of out on the finger tips reducing the leverage forces that will twist a thumb right off or worse if u over welded the permanat adjuster on the back of your stick u could possibly rip or fracture your dipper stick . plus since the grapples are boxed in construction they are much tuffer. the disadvantage is u dont have a bucket anymore for digging purposes.
Ive used hydraulic thumbs but im not a real fan because of the fact that u constantly have to roll the thumb back out since the bucket cylinder over powers the thumb cylinder. one could prob put a heavy duty cylinder on a hydraulic thumb and skip the pressure release but the weight of the cylinder would be so significant it would greatly reduce yer lifting capabilities
after i was done training i was doing some concrete recycling using a thumb and it seemed ackward. but for demo it's awesome.
Anybody seen a thumb like this. It appears to have a bolt-on row of teeth, which I've never seen. Its made by Cat in case the Cat placard is not visible and is attached to a Cat 320 ZTR. Obviously needing some teeth too. It's a local contractors hoe that was in town.
I honestly have never seen replaceable teeth on a thumb. Nor have I really seen the need for such a thing. That is an intersting set up. I wonder if it has a specific application that it meets.
IBT local #174