Torque Wrench use: converting foot pounds to inch pounds

[OB99W]

I've been trying to find an inch-pound beam style torque wrench, but haven't been able to find one yet

I'm not saying this is the place from which to buy, but if you want to get an idea of what's available, see the following page and click on the links at the left:

http://toolsource.com/ost/torque/

[kleinkid]

Usable range of a torque wrench: I work in an industry, nuclear power, where tightening fasteners to a specified torque is is used extensively. Here is one of the standards used: Torque wrenches should be selected such that the applied torque is 20% and 90% (inclusive) of the full range of the torque wrench unless otherwise specified by the applicable component manual.

For example: A 15 to 75 ft-lb torque wrench would be acceptable for any torque value between (75ft-lb X 0.2) or 15ft-lb and (75ft-lb X 0.9) or 67.5ft-lb.

Sometimes 20% and 100% is used. Moral of the story, where it counts, don't use less than 20%.

[nipper]

Usable range of a torque wrench: I work in an industry, nuclear power, where tightening fasteners to a specified torque is is used extensively. Here is one of the standards used: Torque wrenches should be selected such that the applied torque is 20% and 90% (inclusive) of the full range of the torque wrench unless otherwise specified by the applicable component manual.

For example: A 15 to 75 ft-lb torque wrench would be acceptable for any torque value between (75ft-lb X 0.2) or 15ft-lb and (75ft-lb X 0.9) or 67.5ft-lb.

Sometimes 20% and 100% is used. Moral of the story, where it counts, don't use less than 20%.

 

Thats pretty much the standard for all gauges that have any real accuratcy (you get what you pay for again), 70% of full scale, drop the bottom 20 and top 10. Also you canonly eye up the center of two gradiants, meaning if you have a gauge that reads in 10 lb incruments, you can do 5 but not 7 ie 85 as oppsed to 87.

 

nipper

[85-325e]

Math? Nobody told me there would be math on this test!

[Dickensheets]

Some of you guys need to get girlfriends.

[NorthWet]

Some of you guys need to get girlfriends.

Married 27 years next week... explains a few things, eh? You might be right about a GF, but spouse would probably disagree.

[jmickelct]

Hi,

 

Thanks sincerely for the theoretical treatices, but in terms of the actual practical applications, do folks mostly use\own\acquire both a Ft\Lbs and an In\Lbs unit, or simply go as low as a Ft\Lbs (what most on the market seem to be), when closing up stuff that manuals say torque to In\Lbs.

 

Also, having trained in the "crank it down good and it'll be fine" school (last car I did any appreciable work on was my 71' Nova), I now have both units and am in training.

 

Both call themselves "click" units, but confess to really not giving you much of a click (along the lines of a sound of what a rachet might make), but more of a much quieter bump. Not wanting to strip or break too much, can folks share their experience with how you know you've hit your specified unit (short of having these pricey digital units).

 

John

[Andyjo]

Nipper, don't make me find the differential of your soul, then integrate over all space

[NorthWet]

Hi,

 

Thanks sincerely for the theoretical treatices, but in terms of the actual practical applications, do folks mostly use\own\acquire both a Ft\Lbs and an In\Lbs unit, or simply go as low as a Ft\Lbs (what most on the market seem to be), when closing up stuff that manuals say torque to In\Lbs...

Sorry. I guess most of us thought that your orignal question had gotten answered in the first post, and then we got silly, with some useful info intermixed.

 

As I see it, you have 2 choices: Spend big money (relatively) to find a good 1/4" drive torsion beam torque wrench, or learn the fine art of guesstimating low torque values. I have been working with small bolts for 30-odd years and have found nothing more useful than experience. I have also broken a lot of small bolts (mostly early on), some with expensive fixes needed.

[porcupine73]

Hi John, in reponse to your question about what the clicker type torque wrench feels like, well the only ones I've used are the ones from Sears that they just had on sale. When you reach the torque setting, you will feel it give a little bit. You can't miss it. Basically you'll see a pivot point on the wrench, and when you reach torque it pivots a little bit at that point.

 

I don't hear any click, but I can definitely feel it give when torque is reached. That's when to stop turning. I think you'd be fine using it without practice; I used it for the first time for water pump bolts at 7 ft*lbs(f) [84 in*lbs(f)] I think it was and could feel it give just fine.

[jmickelct]

Hi,

 

Thanks again Porcupine...

 

I've got a few years in the trenches, but again, these aluminum deals are pretty new.... I never really considered torquing anything except head gaskets... guess its a new day....

 

Finally ended up with a cheap FtLbs unit as well as the Sears InLpbs unit you mentioned. Have also been paying attention to how much might be enough; have overall been struck with, save for the cam bolts and crank bolt, how everything has been *very* easy to get off.... (so have been trying to err in favor of conservatively cranking).

 

Getting much more comfortable with both units.

 

Curious how much folks go completely on feel, once they get use to what it should feel like.

 

John

 

 

 

Hi John, in reponse to your question about what the clicker type torque wrench feels like, well the only ones I've used are the ones from Sears that they just had on sale. When you reach the torque setting, you will feel it give a little bit. You can't miss it. Basically you'll see a pivot point on the wrench, and when you reach torque it pivots a little bit at that point.

 

I don't hear any click, but I can definitely feel it give when torque is reached. That's when to stop turning. I think you'd be fine using it without practice; I used it for the first time for water pump bolts at 7 ft*lbs(f) [84 in*lbs(f)] I think it was and could feel it give just fine.

[nipper]

Hi,

 

Thanks again Porcupine...

 

I've got a few years in the trenches, but again, these aluminum deals are pretty new.... I never really considered torquing anything except head gaskets... guess its a new day....

 

Finally ended up with a cheap FtLbs unit as well as the Sears InLpbs unit you mentioned. Have also been paying attention to how much might be enough; have overall been struck with, save for the cam bolts and crank bolt, how everything has been *very* easy to get off.... (so have been trying to err in favor of conservatively cranking).

 

Getting much more comfortable with both units.

 

Curious how much folks go completely on feel, once they get use to what it should feel like.

 

John

 

years and years of expeirience, the same way some people can look at a bolt and know what size it, the way others can just eye something then cut it....

 

just practice

 

nipper

[jmickelct]

Hi Nipper,

 

I hear that. I ended up torqueing as much as I could and just "vibbed out" the rest.... broke a few bolt *taking them off*, but just old rusty stuff like one of the overflow tank screws and one of the radiator hold downs.

 

Needed to crank once more on the Vbelts, but, (knock on wood), I'm actually pretty astonished that the damn thing actually runs! (*very happy*.... was really paniced after the left cams did the hula on me).

 

Not only couldnt have done it but wouldnt have even considered the whole thing with out the folks from this listserve...

 

Appreciate all the help (just saved nearly $700!).:-p

 

Cheers,

 

John

 

years and years of expeirience, the same way some people can look at a bolt and know what size it, the way others can just eye something then cut it....

 

just practice

 

nipper