Farm Tractor Skidding

[arbormike]

I have a Ford 4400 I want to skid ash logs with.  But an older, wiser, tree cutter told me to look out! These farm tractors have been known to tip over backwards on the operator if you aren't careful.  He said the best best is to skid them in reverse, hooking the log to the front of the tractor...

Thoughts on this?

[redpowerd]

hook low, those problems may have been encounterd with folks hooking to a 3pt drawbar lifted. always watch the but of the log as it encounters obsticles, the biggest scare i would say is catching a stump and snapping a chain, can happen in the blink of an eye.

[beenthere]

Yes, listen to the older tree cutter. But ----
Go slow, and keep in a low gear. If you are not familiar with what can happen, then you might not be able to react fast enough to stay out of trouble.
But it can be done, and done safely (if you know what you are doing).

As far as "in the blink of an eye", only if the tractor is moving at "blink of the eye" speed. IMO

Fellow woodcutter had an Oliver 550, and had a log lifted on the 3pt and pulling uphill. He had it in low gear, when the log caught on a stump. The front end started coming up. He didn't do any of the three things he could have. 1) lower the 3pt, 2) put in the clutch, or 3) turn off the ignition.   Instead, he jumped off as the front end kept lifting. After he jumped off, I had time to take the 3-4 steps over to the tractor now still rising and turn off the ignition key. So there is no need to panic.

[zopi]

I use a little Long 2360 to skid...just finished putting a half dozen logs on the deck with it..I use a 3 ptboom and tongs..mostly moving stuff around the yard..I lift the logs up off hte ground, completely if possible, and keep a foot close to the clutch...drive slow...and don't operate a tractor without ROPS...

I rarely move tree length logs either...more of them to snag stuff on...

[redpowerd]

im saying that if not looking, and you snag, by the time you turn around you could have a snapped chain. going slow and experience on a tractor surley helps. i may overlook alot of details as im on one daily. like beenthere said be ready with the clutch.

[bull]

Don't drag the logs,choke them short and skid them..... use you three point hitch and lift them off the ground, make a skid plate for the three point hitch if you have the ability. I have been logging with various tractors for over thirty years and have used the same skid plate on all of them from a ford 8n to john deere 3010.... My mainstays are Kubotas 4x4 L195 Ll2550,L4610,M6800 ------ thats 12hp to 70 hp.... never had any trouble.....

[woodmills1]

I always have one foot ready for the clutch and I have a forwarding trailer behind my Kioti and also slow is the word.  you might also look into adding some skid plates around the expensive stuff, debries in the woods can tear things off easily.  both of my Kioti's were set up with the forester package from Payeur

payeur.com

[LorenB]

Arbormike,

Now that I own one, I use my LogRite arch.  That allows me to get at least the end (and sometimes the entire log) off the ground.  This makes it much less likely to catch on a stump, rock or other obstacle.  A log arch is a relatively inexpensive piece of equipment that will increase your level of safety a lot. 

Before I got the log arch, I skidded logs with them connected directly to my farm tractor.  I usually used the 3-point hitch to lift the end of the log off the ground.  The problem with that technique is that you are now pulling from a higher point.  As mentioned before here, you want to pull from as low a point as possible. 

The main thing you can do to stay safe is think ahead.  Be aware of what may happen, and think up a response BEFORE it occurs.  The guy who jumped off his Oliver tractor hadn't thought of what he would do if the front end came up.  (Actually maybe his plan was to jump off, but there were at least three other better alternatives.) 

For example, if you are skidding a log uphill (almost the worst case, sideways on a hill is probably the worst), the most common problem would be that the log catches on something and the pulling load increases tremendously.  This can cause the tractor to start to tip over because the log stops but the tires keep turning, lifting the front end.  ALWAYS be aware that this could happen and have a plan beforehand. 

Think through IN ADVANCE what might happen if the log catches, or if the cable breaks, or if the choker lets go and releases the log, or...

The best safety equipment you have is between your ears. 

You can do this safely, but be careful. 

Good luck,
Loren

[Chuck White]

When skidding with a farm tractor, the biggest danger is flipping over backwards! 

To avoid this, keep the drawbar low! 

Any time the drawbar is even with or above the rear axle, there is the potential for tipping the tractor over! 

[Maine372]

ive yarded well over a thousand cords with a 2004 JD 990 40hp about 5000lb chassis. with a front bucket and farmi winch.

1. start slow and gentle, learn the limits of your machine.
2. plan and build a good road. smooth, level, gentle corners and slopes.
3. use the little notches on the winch for pulling, not the top.
4. get the butts off the ground where they cannot catch on the stumps.
5. cut stumps in the road flush to the ground or dont put your road through a tree (see2)
6. limb your wood thoroughly. dont just cut the branch off, but trim it even with the bole of the tree so it drags easy.
7. front bucket or weights are required. Rops reccomended.

that being said (with 4genlgr as my witness) i have pulled wood with a bicycle, so yes you can do it. just becareful, dont get anxious, let the tractor do the work.

[thecfarm]

Skidders tip over,forwarders tip over,fell bunches tip over,they all do it. I have no idea how many hp a 4400 ford is.Maybe 80hp?The key thing is don't take more than what the tractors will handle,or even close to it.So what if you only get a cord out a day.Better than 2 cords and a tip over.We use to twitch out on a draw bar with a small NAA Ford. No major scary moments. Some people can do what I do in a day,but takes me 3 days to do it.    Just take it slow.I only cut on my land,so I keep all my trails brush free.Now I have a 3 pt winch and that is the only way to go.Don't think you are going to drive over stumps a foot high or rocks either.Plans your trails out the easiest way you can.So what if you have to spend 5 minutes more coming out.Do it right side up is might important to me.Got money for a 3 pt winch? They will last longer than a boat,TV,truck,snowmobile.4 wheeler etc.

[chevytaHOE5674]

If you have the money a 3pt log winch is a great investment. Allows you to keep the tractor on good ground and get logs from swamps/hills/valleys/ etc.

[LorenB]

Any time the drawbar is even with or above the rear axle, there is the potential for tipping the tractor over! 

This is a common error.  Many people think that if the pull on the tractor (the drawbar) is below the axle then the tractor cannot tip over backwards.  This is not true, because the tractor does not pivot around the axle when it tips over.  It pivots around the rear tire/ground contact point. 

The factors (that I can think of right now) that affect tipping (backwards, not side-to-side) are:

• The direction of pull from the cable/chain relative to the rear tires’ contact point
• The weight of the tractor
• How far forward the center of gravity of the tractor is relative to the rear tires’ contact point
• The traction available at the rear tires

To discuss these in order:

• If the pull is very high relative to the rear tires’ contact point, there is more moment arm (or leverage) available for that force to pull the tractor over backwards.
• If the tractor is heavy, it takes a greater pull on the cable to tip it over.
• If the center of gravity is farther forward (by adding weight at the front, for example) the tractor’s weight will have a larger moment arm (leverage) to counteract the pull from the cable.
• If the tires have poor traction, they will slip before they develop enough force to lift the front of the tractor.

Note that there may be more factors than these.  I haven’t sat down and drawn a picture trying to analyze it.  These are the ones I can come up with on the spur of the moment. 

If you can get all these factors working in your favor, you’ll be safer. 

– Loren

[beenthere]

................
This is a common error.  Many people think that if the pull on the tractor (the drawbar) is below the axle then the tractor cannot tip over backwards.  This is not true, because the tractor does not pivot around the axle when it tips over.  It pivots around the rear tire/ground contact point. 
..........

That's a new one on me. Pls explain that a bit more. thanks

[LorenB]

Beenthere,

That's why I mentioned it, because most people don't believe or understand it. 

A proper explanation requires drawing some pictures and showing force vectors.  Engineers call it a "free body diagram".  That's a way to analyze the forces on a single object without having to consider all the other parts of a machine, bridge, truss, or whatever. 

I don't have the time or the ability to draw and post the diagrams required to show the forces, but I'm sure that you can visualize a tractor tipping over.  It doesn't pivot around the axle.  It pivots around the bottom of the rear tire. 

The reason for the rule about keeping the cable below the axle probably originated because if you get the cable low enough, it will break before it can create enough force to tip the tractor over. 

Imagine a tractor pulling a load with the cable attached at the top of the roll bar.  It would tip very easily with a low force on the cable.  As you lower the cable, the force required to tip the tractor becomes higher.  Eventually you will get to the point where the cable can’t produce enough force to tip the tractor without breaking. 

There’s nothing magic about the axle, however.  It all has to do with the relationship between the cable and the bottom of the rear tire.  That’s the moment arm for the cable’s force. 

The tractor is tipped over because of a moment (or torque) produced by the cable’s force multiplied by the cable’s moment arm.  The cable’s moment arm is the perpendicular (to the cable’s direction) distance from the cable to the pivot point, the bottom of the rear tires. 

The tractor is kept upright by the opposing moment of the weight of the tractor multiplied by its moment arm.  That moment arm is the horizontal (perpendicular to gravity) distance from the contact point of the rear tire with the ground to the tractor’s center of gravity. 

If the tipping moment becomes greater than the opposing moment, the tractor will tip over. 

If the tires skid, then the cable will just pull the tractor backwards (if climbing a hill) rather than tipping it over.  If the tractor is traveling on level ground, then the tires will just dig a hole. 

I hope this helps you see what’s going on with the whole thing. 

– Loren

[Gary_C]

  It doesn't pivot around the axle.  It pivots around the bottom of the rear tire. 

There’s nothing magic about the axle, however.  It all has to do with the relationship between the cable and the bottom of the rear tire.  That’s the moment arm for the cable’s force. 

  The cable’s moment arm is the perpendicular (to the cable’s direction) distance from the cable to the pivot point, the bottom of the rear tires. 

I hope this helps you see what’s going on with the whole thing. 

Sorry but I don't agree with any of the above.

First, a "free body diagram" is a method of analyzing ALL the forces and torques on a single object, no exceptions for "other parts."

Second, a free body diagram should only be drawn using the rear axle as a reference point as the problem is to determine which direction the mass of the tractor will rotate around that axle. To transfer all the forces and moment arms to the axle and then to the ground point is confusing, though it can certainly be done. And there is no rotation or pivot point at the bottom of the tire. 

The cable's moment arm must be perpendicular to the point of rotation which is the axle. The difficult part is calculating the forces and angles and then using vectors to determine the force directed to the axle and the force perpendicular to the moment arm that produces the torque on the axle. So it does make a difference if you hook under the axle and as far away as possible.
 
The simple answer to this whole question is to always hook your cable below the axle and as far away (either forward or behind) from the axle as you can. And if you raise the cable and load via the three point hitch, it would be best if the cable was able to slide thru or over that lift point and still be attached below and forward of the rear axle.

[redpowerd]

what if the forces are applied forward of the rear axle? our largest tractors drawbars are attached in front of the hinge under the cab, between the two axles.

[Stephen Alford]

Chocker placement on the tree is important. The chocker should be placed near the butt (wrapped if necessary). A cross piece  will make that easy.  There have been cases where for one reason or another the chocker was up the stem and the tree hooked ,stood up then  fell forward toward tractor and operator.   With smaller diameter trees this can happen very quickly.   

[Magicman]

One simple fact remains......Many folks have been killed skidding logs with farm tractors.  The front end will come off of the ground and they will roll over backwards.

Do I skid logs with a farm tractor.....yes.  I do have ROPS on my tractor and I do wear the lap belt.

[moonhill]

I am reading/following this one as well. 

Tim