Pulling stumps

Anonymous Poster · May 30, 2001

Make sure that any such pulling is done with the chain attached below the axle line. It may seem obvious to use your drawbar but there are many stories of people attaching the chain or line to something above the axle line. In that case the tractor drives out from under the chain hookup, rotates around the axle and flips over backwards.
-Don M

RobS · May 30, 2001

Re: Pulling stumps/Chain Energy

I'm going to have to give this chain versus cable, stored energy some thought. Maybe runs some tests. Off the top of my head, a chain stores energy in discreet amounts (each link) and the energy dissipation in a failure happens in parallel, or each link quickly and simultaneously releasing its energy. A cable or strap stores the energy in the entire length as one unit. A failure releases all that energy in series, more like a spring allowing acceleration of the mass.

Subjectively, consider a cable come-along versus chain and an over-center binder. When releasing the tension on a come-along it feels like a big spring with a fair amount of cable released before it's loose. With the chain binder, it falls limp after very little displacement of the chain.

I know this subject has come up before on TBN. Maybe my seven year old and I can create a "science fair" project to get to the bottom of it. Any suggestions? It'll have to wait for a rainy day when I can't be out on the tractor though /w3tcompact/icons/smile.gif

BigE · May 30, 2001

I have pulled a number of stumps, all though never had much luck just jerking them out. Takes one heck of a machine to pull a stump out of even small stature. I found the best way was to pull with a strap with constant pressure while digging to expose the roots and cutting them when exposed. A lopping shear works real well for the small roots 1" or less. I keep a old chain saw that I don't mind running in the dirt for the rest. Keep rotating around the stump pulling in different directions.
With little Kubota's you have to learn patiance.

Anonymous Poster · May 31, 2001

Re: Pulling stumps/Chain Energy

<font color=blue>Off the top of my head,... a chain stores energy in discreet amounts</font color=blue>

A few years back, I got my Massey 135 stuck deep in the woods...going downhill...

My brother-in-law hooked up his Ford Bronco with a chain and attempted to pull me backwards. All was going well until he "stomped" on the gas to "jerk" me back...

The tow chain snapped midway... I heard a funny buzzing noise past my ear... the chain end hit the loader mount, bounced back and landed next to my right foot... a few more inches...Off the top of my head...

Boondox · May 31, 2001

Pushing stumps?

With Clementine (L3010 with attitude) I've had great luck pushing small trees over (up to nine inch diameter girth) by using the FEL about six feet off the ground and shoving. This works best after a good soaking rain and leaves no troublesome stump to deal with.

Of course not all trees are accessible, and sometimes it's just plain unsafe to try this due to slope, etc. But where I can get at it safely, the tree is toast.

Pete

www.GatewayToVermont.com

RobS · May 31, 2001

Re: Pulling stumps/Chain Energy

John, without a doubt the right tool for "Jerking" is the nylon strap.

I'm still noodling on the chain thing (up all night). I think it boils down to a chain being a series of short springs where a cable (or strap) is one long spring. Statically, it's the same, but dynamically may be a different story. More to come...

skent · May 31, 2001

When I was in the CG stationed in NY harbor, there was this lieutenant that wanted us to pull this old mushroom anchor out (it was visible during low tide and was a left over from a light ship) for use as a lawn orniment in front of his office. Two small boats, a 41' with twin Cat V8 diesels and a 40' steel hull with twin 6 cyl Detriot Diesels went out to try. I was on the crew of the 40 footer. We were using 1.5" double braded nylon, doubled up to each boat, pulling in the same direction. With both boats, (all four engines wide open) we didn't budge the thing, but managed to break one line going to the 41'. When it separated, it whipped past them and hit the coxswains cage (chain link fence attached to a 2" pipe/welded cage designed to protect the operator of the boat in just such an event) on our boat, the cage held, but had to be replaced after that. They ended up sub-contracting the job to a salvage company who used a crane on a barge to get the thing up.

Any time I have to do some serious pulling, I try to use the FEL and pull in reverse. That way I can see what the load is doing without turning around, and I have some protection in the event to a chain or rope breaking. I realize reverse traction is less, but if thats the case, meybe I should consider using something other than the tractor.

Steve

ddl · May 31, 2001

Re: Pulling stumps/Chain Energy

Robs
What is stored in any object is energy, in a spring the amount of energy depends on the spring constant. What causes the spring to bounce once released is the spring returning to its orginal position. A one piece spring can store more energy than a chain made up of links. In theory when pulling with a chain the total energy is the sum of the engeries in each link. A good chain, as tension is applied will not deform, thus stored energy is not as much. Since the deforming is the why energy is stored in a spring, either being streched or compressed. So make sure the chain you are using is high quality, as far as the strap, these were used on the farm alot in the 70's for pulling, after so many breaking and breaking out windows of the tractor cabs, farmer went back to chains. The worst was the stretch straps. Physics must be used and is never wrong.

Dan l

MJB · May 31, 2001

It may not be economically justifiable, but for pulling out stumps nothing beats a backhoe. I just pulled out about 75-80 stumps last night with my JD48 hoe. Most were in the 3" to 4" size but there were a few 6" ones. I was pulling them out so fast I was getting tired just moving back and forth from the backhoe seat to the tractor seat so I could move the tractor to the next stump./w3tcompact/icons/laugh.gif Did I mention that I love my backhoe?

Computers don't make mistakes.... What they do, they do on purpose.

RichS · May 31, 2001

Re: Pulling stumps/Chain Energy

When doing a lot of pulling and yanking, both with chain and strap, I have always put a blanket or something on the chain/strap. Did this many times when off-roading and getting someone unstuck. Things invariably break and not always the chain/strap. Something I read about quite a while ago in a 4wd magazine. Does take a second to throw it over the chain/strap but it does work. Just my two cents.

Rich S.