New cable on 640B- Problems

[George Jones]

Hi everybody,
I run a 1980 JD 640B cable skidder, and have had a bad couple days trying to put a new cable on it.  I have never had to replace a cable before, on any machine.  The old one snapped, it was 3/4 plain cable.  I replaced it with 5/8 swaged, mostly because thats all they had at the saw shop, but I was happy to get a swaged cable because Ive used them in the past and liked them.  Anyways, when I took off the old one, I saw that this skidder doesnt have any way of holding the end of the cable.  I'll try and explain as best I can:  On the drum there is a dish where the ball goes, but it doesnt have any kind of lip at all, or any other way to keep the ball in the dish.  The old cable was tied in an overhand knot around the drum, so that the ball rested in the dish, and was held in place by the cable.  If that makes any sense.  I tried for two days to copy this set up, both alone and with help.  The ball pops out every time.  Today I said enough and drilled and tapped a hole for a 1/4-20 bolt in the drum, which I used to hold a small metal bracket that held the ball in the dish long enough for me to get some tension on the knot.  I dont know if it was ok to put a hole in the drum like this, but I was at a loss for what to do.  It worked, The bracket held long enough for the me to put some pressure on the knot, and it tightened down pretty good.  The bolt and bracket sheared off and got chewed up and spit out on the first hitch, but they had done their job.  HOWEVER, because it is a new cable, it wanted to totally unspool and loosen up on the drum every time I released a load.  I was wary of pulling it out and reeling up tight to the drum, because I didnt want the knot in the end to pop off again, but when I pulled in a hitch on a loose spool, it got all twisted and even started a birdcage, so after that I would drive out every time I reeled in a hitch, to keep tension on the whole line, and keep it nice and snug on the drum.  This worked for about 3 hitches, and then the ball popped out again.  At which point I parked the skidder and walked away.  Anyone who has dealt with before please HELP! I need to be outside pulling wood not sitting at this computer right now..Thanks!!

[jd540b]

George, double the cable over on itself about two feet in length.  Slide the "loop" throught the drum so the loop is sticking out the other side of the drum. Now take the pigtail end and bend it back around the drum so it goes throught the loop.  Pull tension to Tighten it down on itself and it will hold no problem. This works best with the cut off end of the cable.

[jwilly3879]

Did you spool the cable on the drum the same way it was wound? This can cause to unspool wildly.

[coxy]

i welded a piece of  small round stock over the vary end where the cable would fit in the drum then run the uncut end through till the ball falls in place  ill try to get a pic of it if you don't understand what im trying to say im not vary good at explaining things  :D

[cutter88]

I got a 640 and A 540 they both got that stupid set up as well I just make a over hand not

[grassfed]

A couple of questions: Does the cable have a Ball/end knob on both ends? Usually when I buy winch lines for skidders they only have a ball on one end and that is the end that the chokers stop on; it is the end you grab and drag to the tree. The bare end is the end that is fastened to the winch. So I don't understand what you mean when you say dish for the ball on the drum. I would love to see a picture of this if you can.

The other thing is 640B are you sure it is a B model and not a D. I don't think that I have ever seen the 640 Deere skidder in a B model. I always thought that Deere skipped that letter in the 640 range.

One thing no matter how you fasten the cable you should secure the choker end to a stump and cinch the cable by moving the skidder forward slowly then you can winch in the cable .

If there is a hole that has a dished out spot all that you do is pass the cable straight through the way the cable winds on the drum then you bend the cable back and form a bite and pass the bitter end back through the other way next to the cable. you pull out the slack by slowly pulling forward until the bite (u shaped bend) binds in the dish part of the drum. Then winch the skidder toward the stump so the cable winds with some tension on it. 

[Maine logger88]

The Clark I rented last fall had the same setup coxy did except they used flat stock but I don't think it would matter either way only thing to be careful of is not to run your cable all the way out hard it will pop that piece off. Grassfed on some skidders like my 540 i have a 1" or so hole to stick the cable through then on the other end either use a replaceable ferrule or tie a knot. The best set up I've seen is on the hurcules/eaton winch with a little wedge. You are correct on the 640 it goes 640 640D 640E ect. An easy way to tell is what parking brake it has

[coxy]

    i have a lot of weld on mine its pretty tuff but every once in awhile things go south  :D

[George Jones]

Thanks for the advice guys.  The cable had a ball on one end and nothing on the other.  The cable that I removed had a ball on the end that was attached to the drum and a knot on the choker end, so i replicated this set-up.  There is no hole in the drum to pull a cable through, but rather just a small dish, with a kind of ramp going down into it, where the cable runs.  Nothing else, no rim or lip on the dish to hold the ball down, no place where the cable can pass through the drum itself.  The dish appears to be designed to loosely hold a ball or knot end, but of course without some rim, lip, or tie-down there is no way to keep the ball from popping free as the drum rotates away from it. 

Welding on the drum seems like it would work, but the first thing that comes to mind is the drum or some other part of the winch warping from the heat.  It seems to me it would have to be a pretty beefy weld to hold up to the forces present inside a big skidder winch when it is reeling in a hitch.  Im not a welder, so maybe im overestimating the amount of heat that would be generated by such a weld. 

Might very well be a D, the decals are mostly gone from this machine

Thanks again for your advice, I'll keep trying and let you know how it turns out.  The boss is stumped too, he thinks its the cables fault and is going to buy a new one.  I think that this wont change a thing, but its his money. 

[grassfed]

coxy sent me a link to a picture and from that and everyone's description it seems like it should be tied on. If a simple overhand knot won't work try a clove hitch. Once you get clove hitch cinched hard they are pretty secure. Keep the ball in the divot and pull the slack out slowly before you wind the drum. Put some tension on the knot by pulling the skidder forward and then stop lock the brake and rap on the knot with a small sledge or the round side of a cross peen hammer. You don't have to beat the heck out of it but you want to start to mash and kink the cable so the knot gets tight. Then pull the skidder forward a bit to put more strain on the knot and repeat the rapping. After a time or two the knot should start to stick. You could try this method with an overhand knot if you did not try it before. Raping with a hammer really helps set a knot in this situation. Hope this helps. I would not modify the setup because it is just a matter of getting the technique and the right.  knot se it should work