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

[sixdogs]

I new a guy 50 years ago that was a Ford mechanic and used an impact gun for everything. One day I watched in disbelief as he was putting in sparkplugs--in a very expensive car--with an impact gun. I started to kid him a little and he asked if my mother measured everything for a cake. I said no and he said that after enough years of same-old, same-old, you get a pretty good feel and he had been at it for decades. A brilliant mechanic.

He gave me a torque wrench and told me to go ahead and check him. I did and all were within a ft lb of target. He was right on and I shut up.

 

[DaveK OR]

The problem is more likely that you will need more torque than spec to break the bolts loose. Tightening is usually easier.

 

[thepumpguysc]

A torque multiplier and a drop or 2 of loc-tite.. red or blue.. blue is "service removable"..

 

[Oldoak]

Google "Torque Multiplier".

Looks like you can get a Chinese unit for less than $100. The pro level units will be north of $300.

You got it.

Or they do make a torque wrench with a max torque value of 600#. It is 4' long. But I don't think anyone of us would want to pay the price for one.

We used them in the pulp and paper industry along with a 4 to 1 torque multiplier to tighten the hold down nuts on the chippers to 2400#. Glad I don't have to do that anymore. There wasn't the room for a hydraulic torque wrench.

 

[RNeumann]

Dear OP- the tool needed to tighten will need to be slightly smaller than the tool needed to remove the existing nut.

In all seriousness not wanting in invest in 3/4" breaker, big pipe wrench or big impact gun sounds good but how are you going to remove the nut that's on there?

BTW- a lot of the good, higher spec impact wrenches need higher air pressure than some compressors put out. 160psi is ringing a bell but I haven't looked at those specs in years.

 

[RickB]

Dear OP- the tool needed to tighten will need to be slightly smaller than the tool needed to remove the existing nut.

In all seriousness not wanting in invest in 3/4" breaker, big pipe wrench or big impact gun sounds good but how are you going to remove the nut that's on there?

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.

 

[DaveK OR]

Seriously, Harbor Freight probably has the best prices on 3/4" socket sets (around $60, IIRC). That will get you several sockets, a ratchet, a breaker bar, and some extensions. They'll work fine for occasional use. Put a long piece of pipe on the end of the breaker bar to the the torque you need to bust the nut loose. Hit it with penetrating oil first if you can and wait an hour before trying.

As far as torquing the bolt to spec, a torque wrench that goes to 600 ft-lb will cost dearly. The biggest from HF only goes to 300 ft-lb. Your best bet for that is to find a friendly mechanic who can loan or rent you one. The other choice is a little blue loctite (removable, especially if you heat it a LITTLE), and a good guess at the proper force needed. Torque specs are mostly to keep the bolt/nut from coming loose due to mechanical vibrations, and as long as you are reasonably close with the torque, the loctite should prevent self-disassembly. Try to remember how much force you used to remove the bolt and use a little less to tighten it. If you use red loctite, you probably won't ever get the bolt free without heating it up to melt the loctite.

Update... If you really want the 600# torque wrench, check EBay... you can probably find one there, new or used, for around $200 including shipping.

 

[tcartwri]

If you weigh 200lbs, put all your weight on the end of a 3 foot bar. It's that simple.

 

[RickB]

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.

 

[RLstangs]

Bottom-line pricing on Precision Instruments C4D6F at ToolTopia.com
3/4 torque wrench is $345