1100 ft lbs - DIY Torque Wrench Extension

[b-dog]

I thought some of you might enjoy this...
I recently had a nut that needed to be torque'd to 1100 ftlbs and my biggest torque wrench only goes up to 600. My multiplier only goes to 1000 and, for no particular reason, I don't like using that thing anyway. I don't have nor did I want to rent one of those structural electric wrenches and I'm not sure I would have been able to brace it against anything.
Here was my solution, a 4'-6" extension. Multiply the 450 ftlbs torque setting on the 3'-0" torque wrench by 2.5x and voila! At 7 1/2 feet long, this mess is a bit unwieldy but it worked.

 

[Firebrick43]

Adapt and overcome!

 

[couch67]

Wow! what the heck kind of nut needs 1100 ft lbs?

(I'm a bit of an amatueur wrencher and have gotten by with a 150 ft.lb torque wrench lol)

 

[BukitCase]

Torque spec on the biggest hydraulic cylinder(the piston bolt) on my Case backhoe is 1000-1200 ft lbs... Steve

 

[CS454]

Wow! what the heck kind of nut needs 1100 ft lbs?

(I'm a bit of an amatueur wrencher and have gotten by with a 150 ft.lb torque wrench lol)

We have axle nuts that require 1200 lb ft on our equipment. Double barrelled 3/4" torque wrench does them up nicely.

 

[couch67]

Yeah as a backyard mechanic I think the most I've seen is the Honda crank pulley bolt - torque to ** foot lbs (forget target, but around 100), then tighten another 60 deg. Fine going on, not so much when coming off.

 

[BukitCase]

There are entire different worlds out there with vastly different scale that people who haven't seen them up close, have no concept of - my last 34 years before retirement I worked in instrumentation in rare metals plants - we had hydraulic forge presses that used cylinders with 3 FOOT diameter rods - each 4 foot long stroke took 250 GALLONS of hydraulic fluid plus another 450 gallons for the two slightly smaller cylinders flanking the center one - there were 3 separate pumps, each with a 300 horsepower motor, and the press could re-shape a 20 foot long, up to 40" diameter, typically 20-25 ton ingot of Zirconium into a 6" thick slab, in 3 or 4 passes. the jaws of the press were a little over 8 feet long and 2 feet wide. You could feel the heat coming off those ingots from over 100 feet away.

There's a machinist on another board who works in mining; he routinely line bores bearings on big mine shovels, the pivot pins are 16" ID, IIRC - the typical dump truck you see on the road holds 12 cubic yards - by comparison, the bigger mine "shovels" (excavators are a smaller version) - the mine shovels' buckets hold 65-70 cubic yards, and it takes 3 or 4 buckets full to load ONE truck.

It's a little bit like thinking you know how big a bengal tiger is, BEFORE you actually see one in person... Steve

 

[b-dog]

haha I was torquing pinion nuts on a military truck axle.

I work for a crane company and we've used up to 1 1/2" structural nuts which require up to 3,500 ftlbs. Totally different application/tools/methods that wouldn't work for what I needed.

Double barrelled 3/4" torque wrench does them up nicely.

What is this?!

 

[CS454]

What is this?!

I'll grab a pic of it tomorrow for you, goes to 1500 lb ft. We use them on ZF Bus axles.

 

[CS454]

Update, I'm a hack and a fraud. It goes to 1000 Lb Ft and 1500nm. The axle torque spec I quoted above is in nm, as per my service literature.

Anyways, people like pics right?

 

[Wpavlis]

I did a similar thing for the u bolts on my 68 chevy c10. I couldn't afford to purchase a 3/4 torque wrench for 4 nuts. welded up something similar, but it was only 24" long.

 

[jubilee]

There are readily available formulas for computing torque by adding extensions (cheaters) to torque wrenches.
I’ve been using them for years, but for field work I use a beam torque wrench, non flexible cheater, and add 15-20%... gets very close to doing all the math.

 

[b-dog]

Update, I'm a hack and a fraud. It goes to 1000 Lb Ft and 1500nm. The axle torque spec I quoted above is in nm, as per my service literature.

Anyways, people like pics right?

That's awesome, I've never seen or heard of such a thing.