How tight is tight enough - Can anyone identify with these pictures?

[Emop]

These has been many "how tight" discussions on this forum, and others, regardless of of the type of gun being discussed. It's an important question and one that rarely gets resolved unless actual torque values and torque tools are available and explained. The most common answer is snug, and other "by feel" explanations that no two individuals can interpret in the same way. Does that make it important and worth bringing up again? Probably not because most fasteners are under-tightened, either by fear of over-tighnening, or the explosion of every trigger pull and the resulting vibration that slowly loosens them. But the solution is simple… re-tighten them. Correct? Maybe.

I was reading an older thread not too long ago about properly tightening extractor rods. This particular topic has some additional and more complicated consequences than many other "how tight" questions. An extractor that loosened up from insufficient torque can result in a fully locked up and useless revolver that often needs the professional help of a qualified gunsmith to remedy the problem. Not fun for anyone that its happened to, and potentially dangerous if it happens to be your personal carry weapon. There are actual tested torque values available for many of the fasteners on our revolvers. For extractor rods, from Kuhnhausen's S&W Shop Manual. It's 45 inch Lbs, and 55+ that can cause threads to stretch or shear off. There's also a couple of nice tools available to tighten them safely without bending or buggering up. What I have not been able to find is a tool to measure the recommended torque except the one in the photos that Brownell's stopped making many years ago, and I can not find anything remotely similar today, or any other tool that would get this particular torquing job done? The photos show a simple tool that isn't perfect but something a machinist could probably make without much fuss, but I am not a machinist or a gunsmith but I do have a background in engineering and physics and a good understanding of screw dynamics. This is why I ask these sort of questions. Because, believe it or not… it often matters, and sometimes quite a bit... And when someone tells me to do it by feel, I simply don't have the experience to translate that into useful information. Like some of us, I rather have something more empirical to go by, that can be as simple as a practiced reference... or the peace of mind I get from the dreaded torque wrench. Other than scope attachments, the information I've gathered from gun forums regarding the use of a torque driver can leave a budding gun enthusiast feeling that using one is on par with wearing adult diapers. Am I not butch enough to tighten my screws without the confidence to fly solo? I also don't open my beer bottles with my teeth either!
Thank you.

Let me know if the photos look familiar or if they stir your imagination? Please refrain from an 1/8 of an inch more after it begins to snug-up, if possible!

 

[SeamasterSig]

I had a cylinder rod loosen up and put an end to my range outing. Fortunately, a gunsmith was on-site at the indoor range. FWIW, what about using blue loc-tite? That should at least help keep the pesky screws from backing out, even if they are a little undertorqued.

 

[TAROMAN]

Nice idea.
I would recommend a beam type rather than a click torque wrench.
With one, it's possible to "sneak up" on the desired value.

 

[Emop]

Nice idea.
I would recommend a beam type rather than a click torque wrench.
With one, it's possible to "sneak up" on the desired value.

Thats actually a good idea.
The other issue I see with this set-up is you're pressing against thin brass cases that will absorb an uncertain amount of pressure as they distort (dent) that may lead to a false reading?

 

[rct269]

Well, the torque wrench looks familiar---which is to say it appears to be of the "clicker" type---and given its use illustrated here, it's calibrated in inch-pounds. I can tell you it's not cheap---and it's worth every penny---and then some. The attachment thereto used to turn the cylinder is so simple as to border on sheer genius. The clamp used to secure the ejector rod is one of many---ranging from a couple of small soft wood blocks (to hold the rod) in the jaws of a vise (which I have used for years)---having recently graduated to an old heavy leather belt in lieu of the wood blocks. I have several store-bought gizzies to hold the rod, but have never mustered up the courage to use them for fear they'll slip and mar the rod.

Given MANY years of turning wrenches on all manner of fasteners on race cars and airplanes, I use torque wrenches on the big stuff; and my God given good sense on most of the obviously fragile little stuff---and never ruined anything---nor had anything come loose. I have a (sort of) inch pound clicker torque wrench which doesn't click, but breaks away (disconnects) when a pre-set value is reached. It's capacity is 0 to 45 inch pounds, so it's use is limited to truly delicate fasteners. It's a one hand tool (think screw driver) with a 1/4" drive. It's older than dirt, still spot on accurate, and may or may not still be available. The brand is "BRITOOL", made in England, and is referred to as TURNTORQ DR 57. I have an "el cheapo" Craftsman beam reading torque wrench for checking preloads (bearings and such) which is useless/inaccurate for our needs (given a capacity of 0 to 600 inch pounds).

Your title gave me a good laugh! Way back when I wasn't really sure which end of a wrench to hold onto, I was under the Boss Lady's car installing new shock absorbers. I was being assisted by a friend who just barely knew which end to hold onto. I was on a 5/16" bolt-----which at once is a decent size fastener, and surprisingly easy to twist into two pieces. I called out from under the car-----"How tight is tight?" My question was punctuated by a loud SNAP as the bolt broke. "Not that tight.", came the reply.

Having been there and done that, I can tell you NOTHING beats GOOD tools. Having been inappropriately frugal on occasion in my not quite ripe youth, I can tell you Snap-On and Proto make GOOD torque wrenches---those which maintain their accuracy----passing muster every time they're tested. My favorite light duty torque wrench is a 3/8" drive Proto clicker (5-75 foot pounds) I bought used maybe 55 years ago---and which passed muster just about a year ago---spot on the money!!---throughout the range!!!!

When in doubt, buy the most expensive option. It will prove its value.

Ralph Tremaine

 

[chief38]

This is a subject that for me has been easy to master but difficult to explain to others. It's almost impossible to "explain" torque over the internet.

I own 3 torque wrenches but will admit to rarely using them anymore. On Firearms I never use them. I have been at this for a long long time and don't even give any thought to how tight to make a fastener anymore - it just comes naturally. I've got a tool of some sort in my hands almost every day and YES it's all about "the feel".

I wish I could be of more help, but how does one explain proper torque over a forum without expressing it in inch or foot pounds? If you were here I could demonstrate so that I could hand you a properly fastened screw, bolt and nut of certain sizes and let you try and get a feel for it.

Sorry I can't be of more assistance, but it's like trying to explain how hard and how fast to increase the pressure on a trigger with your finger while target shooting.

 

[2152hq]

I've been at this for 45+yrs and IMO it's not so much that a torque wrench wouldn't be helpful in some situations, but that in most all situations you just don't have any reference about what torque to be applied in tightening.

Thousands of different guns with tens of thousands of different screws in them of all types doing all sorts of things.
I honestly can't ever remember a torque spec for any of them.
But I don't get into stuff build after about 1970 or so.

It truly is your experience that tells you how much, too much and not enough.

When a bbl won't come off of a recv'r w/o the use of a 6ft cheater bar placed over the action wrench,,,that's probably torqued in place 'pretty tight'. But that's all I care about as far as a spec.

When I put the new or replacement back on, it's going on with the action wrench (12" handle) freely turning the action into place till the last 1/4 turn or a bit less. Then with that same action wrench handle, I pull the action into alaignment with the bbl.
That's 'tight enough',,a 'light crush fit',,however you want to say it.
What is the torque spec,,,I don't know.
But my experience tells me it's correct.

 

[Steve912]

Torquemada

Probably not because most fasteners are under-tightened, either by fear of over-tighnening, or the explosion of every trigger pull and the resulting vibration that slowly loosens them.

I asked a couple of crusty automotive warrant officers (Army
type) if people generally under- or over-torqued fasteners.
The both simultaneously exclaimed "OVER!!"...as in "usually
way over", the torque spec.

I would recommend a beam type rather than a click torque wrench.
With one, it's possible to "sneak up" on the desired value.

You can do that with a clicker, too. Just set a series of lower
values, and work your way up to the spec. Nothing says you have to do it all in one swoop.

 

[lebomm]

Quoting Emop;
"Like some of us, I rather have something more imperial to go by....."
I bet you probably meant "empirical", as regards data. The Imperial, or English system is the one we use involving feet, inches, pounds, ounces, and so on rather that the metric system of meters and grams. Metric data can be empirical, but not imperial.

Hope this helps,
Larry

 

[Emop]

Quoting Emop;
"Like some of us, I rather have something more imperial to go by....."
I bet you probably meant "empirical", as regards data. The Imperial, or English system is the one we use involving feet, inches, pounds, ounces, and so on rather that the metric system of meters and grams. Metric data can be empirical, but not imperial.

Hope this helps,
Larry

yes, thanks for catching that... empirical was what I was going for. I'll make the edit now.