Northern Industrial Torque Multiplier Set
I like it
I needed a little extra torque to remove lugnuts from my Semi and this tool did the trick wonderfully. I would definitely recommend it. I'm not sure how it would do for someone that needs it everyday but great for the occasional user.
August 13, 2012
needs handle extension
Overall, this is a great unit which packs enough punch to bust free rusted lug nuts. It has never failed to free any of them for me. However, on big tires at the higher lug nut positions, the ratchet handle has nothing to bear against. I had to use an extension piece of 1in galv pipe over the ratchet.
December 21, 2011
Torque Multiplier Usage
This product is an excellent value, and I would recommend it to anyone who repairs farm, logging, mining, or construction machinery, and heavy trucks. At less than 1/10th the combined cost of a one inch air impact wrench and a big portable air compressor, this torque multiplier can do the same job, and even some more precise tasks. And it can be hand carried to the work site if equipment breaks down in a place that is inaccessable to a service truck. Every powerful tool needs to be used with discretion. The rated output of this torque multiplier is more than enough to break 3/4 inch bolts or wheel studs, or to twist the square end off of a frozen inside dual nut for Budd wheels.The tool designer expects that mechanics will likely use cheater pipes to increase the leverage of the tool handles, because it would take a 434 pound mechanic stepping or hanging with all his weight at the end of the 18 inch ratchet handle in a nearly horizontal position, to acheive the max input torque of 650 ft-lbs, times the mechanical advantage factor of 3 equals an out put torque of 1950ft-lbs. But the pricing indicates there is no intention of limiting sales only to Sumo wrestlers. Substitute your own weight for "w" in this formula ["w" lbs. X 1.5 ft. X 3 = ft-lbs output torque] to see how much torque you could put on a lug nut using this torque multiplier and ratchet without using cheater pipes.
Having some concept of how much leverage and force is appropriate in any particular situation can prevent skinned knuckles or more serious injuries, as well as prevent a repair job from becomming a bigger, costlier repair job. Note that published torque specifications apply to the task of putting something together, not to the task of taking something apart; however the specification is a good starting place from which to progressively work up to greater force and leverage when trying to remove a fastener, but do not use a torque wrench for this task as the sudden shock when a fastener pops loose or breaks can do bad things to a precision measuring tool. Torque specifications are intended to get fasteners and the parts being fastened sufficiently tightened to prevent vibrating loose, but not so tight as to risk breakage, and are developed presuming clean, lightly oiled fasteners in new condition. Where multiple fasteners are employed, an additional purpose is to distribute the stresses more or less uniformly to minimize warping. The competent repair mechanic seeks to achieve the purposes of the torque specification rather than just adhering rigorously to the published numbers; since used fasteners will have stretched, might have minor dings to the threads, and perhaps cannot be completely cleaned up to remove all paint, rust, dirt, carbon, dried lubricant, water or ice, etc under field repair conditions. In general with smaller fasteners, never tighten in excess of the torque spec, and with large used fasteners, avoid tightening more than ten percent above the published torque spec. When trying to loosen a fastener, limit your brute force only approach to about 120 percent of the published torque specification. (A small easy to carry acetylene welding torch outfit is an ideal companion tool for these jobs). Judicious application of heat and the liberal use of penetrating oil can usually make it possible to get things apart without destroying anything. If this does not work, use more heat and progressively increase the torque by about five percent increments, but be prepared for something to break suddenly, or consider using cutting tools to remove the fastener.
Now back to getting the mental concept of appropriate leverage and force to employ when using this torque multiplier and ratchet. If you are putting things together and have a suitable torque wrench available, by all means use it, but never extend the handle of a torque wrench with a cheater pipe. If its torque range is below the desired specification, connect it to the input of the torque multiplier, with a 1/2 to 3/4 adapter if necessary, and use the mechanical advantage factor for your torque multiplier, (in this case 3), times the observed or set (click) torque as the output value. There will be some minor torque losses due to friction, flexing, etc., but don't sweat the small stuff when torquing big fasteners.
In the absence of a torque measuring wrench, a mechanic can still achieve sufficiently accurate torque by doing a little math, measuring the appropriate leverage, and applying a known force or weight at that point. Old heavy equipment shop manuals and WW2 vintage military tech manuals had examples of using a long cheater pipe, a small spring scale, a bucket of sand or other known weight, a rope, a pulley to change direction of applied force, a small block and tackle, etc to accomplish precision torquing. The math is easy. Divide the desired torque by the known weight to get the required leverage. If using a torque multiplier divide the previous result by the mechanical advantage factor. A mechanic can spend a little time in a wieght room , or using a weight machine at a health club to get a pretty good idea how much he can push or pull with his arms, and push with his legs. This will give him an estimate of the force he can employ when working in circumstances where he can not get in position to use his full body weight. This comment is getting long. You won't regret buying this torque multiplier and ratchet combo.
June 3, 2010
Unless you are using a calibrated torque wrench for the input to this multiplier you really have no idea what you are getting from the output end. A ratchet is not a calibrated torque wrench.
Also, since there is no accuracy spec for the multiplier you are shooting in the dark - is it +/- 10%?
I would say this is a good tool for removing rusty nuts, but not for accurate tightening.
January 5, 2010
I bought this tool to change the cutter blades on a John Deere MX-5 Bushhog. It worked perfectly without even having to use a pipe extension. Great back saver.
November 2, 2009
Well built solid tool
The tool is well built and the finish is very good. Works as advertised.
The lug nuts on my motor home require 475 foot pounds of torque. I have road service and won't be changing a tire myself, but I have yet to see a road service truck with the equipment necessary to properly torque the nuts.
Most motor home service shops and tire shops don't have it either. Most seem to just run the impact wrench all the way up and let it go.
The only drawback is the cost of the sockets and extensions needed for the one inch output drive. On the other hand when dealing with torque in the 475 (or higher) ft pound torque range, the big sockets and extensions have a great solid feel with no torsional twist.
July 24, 2009
The torque muliplier works very well for me in tightening or removing blades on brush cutters. And with the use of an adapter I can get them to the proper torque using my 1/2" drive torque wrench.
August 18, 2008
Accurate. Nice fit, finish & quality. Great value for the money.
January 21, 2008
This is a great Tool very well constructed. The rachet is handy. This is a super alternitive to the snap on version that cost over a 1000 dollars. I have used this items 20 + times now in a variaty of jobs. It's great for removing lug nuts on heavy trucks and for high ft-lb torque spec bolts. The case is kinda bulky but it does work.
March 7, 2007