How do you get 600 ft/lbs torque on a rotary cutter blade nut?!?

[CADplans]

Skinny people need not apply for this job,,,

:laughing:

 

[joefromga]

You're not supposed to use an extension handle on a torque wrench. It will damage the wrench and be inaccurate.

You're supposed to extend the part between the head and the nut using a pre-made extension or make your own by welding a socket to a bar on one end that has a square hole for your torque head on the other end. Then you use a math equation to figure out the multiplier.

 

[sixdogs]

Few, if ANY discount 3/4" drive socket sets will have the reqiured 1-11/16" socket that fits a Bush Hog blade nut properly. Some of the more mainstream brands also skip that size.
That's why I advocated a Bush Hog blade nut wrench, a 24" pipe wrench, and a cheater. A good way to go if you have little need for a 3/4" drive set, especially if one buys a set only to find it won't do the job it was purchased to do.

There is a 1 11/16", 3/4" or 1" drive socket in my seldom used Harbor Freight set. I adapted my 1/2" HF Earthquake impact gun up to a similar sized socket by using adaptors and took a nasty and stuck nut off last year. Impacted the new one on and it's been fine ever since. Took less time to do that than answer this post. I'd bet the factory puts them on with an impact gun.

 

[truckdiagnostics]

http://www.northerntool.com/shop/tools/product_200619498_200619498 Milwaukee M18 FUEL 1/2in
something like the above? not cheap by any means. I have a 1/2 dewalt that is battery operated only puts out 300 ft lbs so won't work for you, but my point is I like it, saves dragging out air hose. We are using more battery operated impacts in the shop, mostly the small 3/8, i am impressed with what they will do. Worth a look and you won't need a compressor.

 

[JimRB]

I don't know what the factory uses to torque those blade bolts down but I bought a less than year old brush cutter than had loose bolts on both blades. Deck was dinged up in a big circle from this, I guess. I used my Titan 40" 3/4" drive breaker bar to tighten the nuts up. I do not recall if I added a persuader to the breaker bar. Anyhow good and tight was how tight they got. Much tighter than quite loose and floppy. I kind of like using hand tools to torque things, I do not trust impact tools. Maybe if I used impact tools every day I might have more faith. I do have three smaller quality torque wrenches but nothing in 3/4' drive.

 

[DaveK OR]

Few, if ANY discount 3/4" drive socket sets will have the reqiured 1-11/16" socket that fits a Bush Hog blade nut properly.

Well, there is that little detail. I hate it when manufacturers use oddball sizes just so they can then sell a special tool to fit.

You can buy this socket at Sears for about $20. Or then, you might try e-bay for the socket. You still want a 3/4" drive breaker bar to go with it.

 

[DaveK OR]

I'd bet the factory puts them on with an impact gun.

LOL! I ran into that very issue when dismounting my backhoe from the Woods shipping skid. It was held to the skid by metal tabs, on one end, a common 3/8" nut and bolt, while on the other 3/4" bolts that attached where 4-point brackets would go. That 3/4" bolt took somewhere around 400 ft-lb to break loose (standing on the end of a 30" breaker bar, and than having to bounce on it!), even though the proper torque on a bolt of that size would be around 200 ft-lb. And for a shipping skid, I'd say hand-tight with blue loctite would be enough.

 

[dnw64]

...for a shipping skid, I'd say hand-tight with blue loctite would be enough.

Seriously? Taking the time to put Loctite on a shipping skid? They just use their 1/2" impact gun set at Max and assume that anyone buying such equipment will have whatever is necessary to remove it, by hook or crook.

 

[mapper]

My neighbor, a retired industrial mechanic and millwright, helped me replace my brush hog blades. We torqued them to the maximum torque with a 1/2" torque wrench (250#?), then he marked one flat on the nut and its location on the seat. He then turned the nut 1/6th of a turn more, using a 3/4 breaker bar and short cheater. He explained to me that any more would just be stretching the threads on the bolt. It never has come loose unintentionally.

 

[RNeumann]

Nowhere did he say he didn't want to invest in hand tools. He doesn't want to buy a big air powered impact and the compressor to run it. And I don't blame him.

My bad- read that part too fast