Woods 72" cutter blade torque question

[Noobie]

Woods 72\" cutter blade torque question

I recently purchased a New Holland TC40DA with a Woods 72" brush bull. I have cut about 15 acres so far and when I went out this morning to start cutting again, I found something wierd while inspecting the cutter. The blades were loose at the attachment of the crossbar so that they could rotate about that bolt. I assume that the dealer/manufacturer didn't torque them down enough and I should go try to find the right sized socket to torque them down, but I wanted to ask first to make sure. The manual doesn't say how tight to torque the nuts in the blade removal section, and it has a torque chart according to nut size that doesn't look like it goes big enough for these nuts. See attached picture for what the blades look like right now.

Any advice? Assuming I should tighten them down, I read some of the threads about tightening the nuts so it looks like I just need to go find the right socket or a cresent wrench to fit and something to block the other blade. Is that about it?

Thanks, David

 

[Inspector507]

Re: Woods 72\" cutter blade torque question

I don't have a brush hog, but I think the baldes are supossed to do that. They will swing out where they need to be at PTO speed. They need to swing away if you hit something.

 

[Indydirtfarmer]

Re: Woods 72\" cutter blade torque question

That Woods Brush Bull won't have a bolt/nut arraingment to "torque" the blade. It has a pin, held in place with a smaller bolt to secure the blade. IF, and I stress IF the blade is in fact, too loose, it takes some special shims to tighten it up. Those should be available through your local Woods dealer.

I suspect that the blades are in fact, OK... They should be loose on the end of the cross bar (or stumpjumper if equipped) After a few hours of use, the blade tips should have a small amount of up/down movement. (Usually 1/4" or so is not out of the ordinary) In any event, you don't want them "tight".

 

[have_blue]

Re: Woods 72\" cutter blade torque question

Not to worry. Brush hog blades have a "flail" action. That is to say, they hinge freely on a large pivot bolt secured by the big nut you saw. Centrifugal force slings the blades out to the maximum 72" diameter when cutting. If the blades strike something massive, such as a stump or dirt hill, they hinge out of the way. This prevents damage to the blades, drive train, and tractor.

Welcome aboard!

 

[Bird]

Re: Woods 72\" cutter blade torque question

David, you do want the nuts that hold the blades on to be tight, but you also want those blades to swing freely. The ones I'm familiar with are a bolt with a shoulder on them. The blade has a bigger hole to go around that shoulder and still swing freely, while the threaded end of the bolt goes through a smaller hole on the stump jumper and then the nut. So matter how tight you get the nut, it can't pull the shoulder on the bolt through that smaller hole and put the blade in a bind.

 

[Clyde]

Re: Woods 72\" cutter blade torque question

IndyDirtFarmer is taking you in the right direction and the rest of the posts to your "problem?" are right on course too. The blades have to pivot off the center circular plate so they can swing back when hitting an immovable object. If the end of the blades has more than a 1/4" up from center and down from center(1/2"total), you should request shims from Woods in Oregon, IL free of charge. Their website is www.woodsonline.com. They are a friendly and accomodating company to work with. I'd start with my dealer as he should have the shims in his inventory. The dealer should be your first point of contact and if the freeplay is excessive - he should have caught it in his predelivery inspection.

No offense to any dealer but they give all sorts of reasons of warranting a profit margin above and beyond factory dealer prices. If you don't have a owner's manual - demand one - it's your right. Then read it, understand it, and then if any questions - ask your dealer first. I really think you're 720 Brush Bull is within factory limits.

Good Luck - Clyde

 

[Noobie]

Re: Woods 72\" cutter blade torque question

Thanks for all the help and hand holding. I think this is one of those cases where I overthought the problem a bit. I definitely see the reasons why it is arranged as it is, but once I got the idea in my head that it wasn't right, I was sure if I started it up I would regret it. I did indeed get a manual and read all the way through it, but never found an answer, but I might have been looking for the wrong question (How much torque rather than should the blades rotate freely).

Thanks again.