torque wrenching VS tighten by feel

[Snappy]

Question is : Do you use a TW or do you tighten by feel and why?

Personally , I feel more comfortable using a TW on certain applications such as aluminum heads. I still have a sense of feel if something is going wrong while tightening.

 

[myslow2002gt]

On every engine build, I use a combination of a stretch gauge and a torque wrench.

On almost everything else (including spark plug changes), I never use a torque wrench.

 

[Merkava_4]

Question is : Do you use a TW or do you tighten by feel and why?

That's just it, I use a torque wrench when I can't feel.

Applications where you're compressing a spongy gasket will usually require a torque wrench because if you keep cranking down until you feel it getting tight, by then it's too late, the gasket is ruined.

 

[yellowbox]

tighten by feel
unless it is an engine rebuild or something of that nature
everything else gets tightened by years of experience .....

 

[spoolin spec v]

That's just it, I use a torque wrench when I can't feel.

Applications where you're compressing a spongy gasket will usually require a torque wrench because if you keep cranking down until you feel it getting tight, by then it's too late, the gasket is ruined.

I agree.

oil pans, valve covers, IM gaskets on most cars, I will ALWAYS use a tq. wrench. Other items, I just go by feel, or 3/8 impact / Air ratchet

 

[Danglerb]

Mechanics not using a torque wrench are why I work on my cars myself.

When I tighten things by feel, its when it doesn't have a torque spec, and I am spending my own dime if I screw up. I don't like paying for expertise and having corners cut to make the job go faster.

 

[Elroy]

tighten by feel
unless it is an engine rebuild or something of that nature
everything else gets tightened by years of experience .....

Same here.

If you need a torque wrench to assemble a thermostat housing or a air cleaner wing nut then you're not much of a mechanic.

Remember: Ya gots to have the feel

 

[caper]

Mechanics not using a torque wrench are why I work on my cars myself.

When I tighten things by feel, its when it doesn't have a torque spec, and I am spending my own dime if I screw up. I don't like paying for expertise and having corners cut to make the job go faster.

EVERYTHING has a torque spec,find the size/grade of fastener and there's a chart available that gives the torque.That said I tighten by feel for the most part with the exception of gasketed surfaces.We use a torque wrench to check fasteners on our aerial devices to 90% of original torque yearly.Any critical fasteners like pintle hitch mounting bolts,lug nuts and anything on a boom get a torque wrench.

 

[Junkman]

1/4 turn before it breaks or strips and all done by feel. The cars love the feel of experianced hands...

 

[rsanter]

all critical applications such as heads, mains, con rods....even lug nuts I use a torque wrench

bob

 

[Boltthrower]

Same here.

If you need a torque wrench to assemble a thermostat housing or a air cleaner wing nut then you're not much of a mechanic.

Remember: Ya gots to have the feel

I know an aircraft mechanic or two who might take offense to that statement.

 

[GDA]

All these posts indicate that many prefer to tighten by feel and use their experience to do it right, but no one offers how feel and all these years of experience were obtained so that their feel is dialed in at the right spec or torque? No one got it right out of the box.

I always use a torque wrench because I'm not a pro and slowly am learning the feel through the use of my torque wrenches. I'll still probably always use a trq wrench though.

 

[Autoguy]

You need to be very carefull with those modern aluminum head and block engines. There is no space for errors like the old cast iron ones.

 

[Canadian Charlie]

I'll always use a torque wrench on engine rebuilds or whatever. But I've never used it to tighten wheels on my cars instead use the torque sticks.

 

[-B-]

With the prevalence of light weight low clamping strength materials in the cycling community I have to use a torque wrench on virtually everything on a bike. Back in the day parts were made with far more tapers and stronger clamping areas to last for decades instead of a few seasons. Tapers require a mechanic to be able to feel when they are interlocked correctly ( there are TQ figures for them but they are notoriously low ) tapers also have to be put together dry as any lube will compromise the part and fit. In the past few years I have seen and had far too many TQ wrenches fail or need recalibration far too often in the cycling industry. Industral/ production TQ wrenches are the only way to go for the pro that uses them every day 100+ time a day.

 

[Elroy]

I know an aircraft mechanic or two who might take offense to that statement.

Why? Because they don't have the feel? Because they have never experienced a rusty bolt stretch. Because they spend all their time following rigid guide lines that spell out exactly when and how something has to be done. Because they never had to improvise they just had to fill out the forms. Never had to get the tractor started and the crops harvested before the rain or frost.

Know this: Some of the BEST mechanics are tractor mechanics and they seldom use a torque wrench. They use something much more valuable. They use common sense as the first tool.

 

[walrus]

Why? Because they don't have the feel? Because they have never experienced a rusty bolt stretch. Because they spend all their time following rigid guide lines that spell out exactly when and how something has to be done. Because they never had to improvise they just had to fill out the forms. Never had to get the tractor started and the crops harvested before the rain or frost.

Know this: Some of the BEST mechanics are tractor mechanics and they seldom use a torque wrench. They use something much more valuable. They use common sense as the first tool.

Are you saying any good aircraft mechanic should be able to do his job by feel and common sense?

 

[kidatari]

Are you saying any good aircraft mechanic should be able to do his job by feel and common sense?

As an ex-aircraft mechanic, a good portion of aircraft mechanics do not have the necessary common sense to be trusted to use their 'calibrated elbow'.

Me, I use a torque wrench on anything load bearing or moving. The smaller stuff gets torqued by feel.

 

[kiall1987]

Why? Because they don't have the feel? Because they have never experienced a rusty bolt stretch. Because they spend all their time following rigid guide lines that spell out exactly when and how something has to be done. Because they never had to improvise they just had to fill out the forms. Never had to get the tractor started and the crops harvested before the rain or frost.

Know this: Some of the BEST mechanics are tractor mechanics and they seldom use a torque wrench. They use something much more valuable. They use common sense as the first tool.

So true , you can't turn up in the middle off a field and say "nope pal, cant tighten that theirs no torque spec for it !" you'll soon see a farmer tighten a allan cap bolt with a shifter to get the work done. But critical , engine , wheels, load bearing bolts then ill torque when I can get the info

 

[Elroy]

Are you saying any good aircraft mechanic should be able to do his job by feel and common sense?

Yes, while being augmented with the proper tools procedures and specifications.

Elroys *** gets chaffed when someone says. "Oh I use a torque wrench on EVERYTHING epecially the ash tray hinge bolts"

YA ********.

 

[A_Pmech]

Why? Because they don't have the feel? Because they have never experienced a rusty bolt stretch. Because they spend all their time following rigid guide lines that spell out exactly when and how something has to be done. Because they never had to improvise they just had to fill out the forms. Never had to get the tractor started and the crops harvested before the rain or frost.

Know this: Some of the BEST mechanics are tractor mechanics and they seldom use a torque wrench. They use something much more valuable. They use common sense as the first tool.

When a tractor craps out, the farmer pulls off the road and waits for some more baling wire. When an airplane has a problem, there's nowhere to pull off and wait. If that happens to be over the North Atlantic at 5am, with a heavy sea, some people are going to die that morning. That's why.

Aircraft structures are some of the most heavily stressed structures on the planet. They have to be, if they are to fly. As a consequence, the margin for error in their maintenance is minimal, unlike a tractor. They must be continually inspected with a fine-tooth comb, to find problems BEFORE they turn into emergencies. The concept of maintenance is something farmers don't seem to grasp, if the number of guys lined up at the parts counter with panicked looks during planting and harvesting seasons are any indication.

It also has to do with following the approved service instructions and aircraft maintenance records. You can choose to ignore the service instructions for your Chevy. However, when working on an airplane, we are REQUIRED to follow the written service instructions, when available.

When we're done working on an airplane, even if it involves changing a lightbulb, we are required by law to sign our name and certificate number on the dotted line in the appropriate logbook. In some cases, the words "I certifiy this *** has been inspected IAW an *** inspection and has been determined to be in airworthy condition." Not "Bubba was here", Certify... That means, if anything breaks on that airplane in service, we're the grass and the FAA is the lawnmower. Those logbooks follow the airframe, engine, or propeller for their lifetime, so the "Certify" part never disappears or is erased. Our names are forever linked to that piece of machinery.

Are you qualified to sign your name in one of those logbooks, Elroy?

Maybe if you were, you'd understand why we take things so seriously. Getting a phone call from the FAA or NTSB at 2am is NOT one of the things we look forward to in this business. In our business, there is no such thing as a "second chance" to get it right.

 

[Delray]

Heads and intakes I normally torque in pattern by increments of 33% 66% 100%. Oil pan, ****** pan, valve covers and such are easily bent by over torquing and will leak between the fasteners. That said I usually do them by feel. I don't normally torque wheels but I do tighten in increments with pattern.

 

[-B-]

I broke a 1" bolt under the direction of someone else I told them it was thigh enough I was told to keep going as I could not possible have gotten it tight enough. After it broke and nearly injured me, I went after the offender my partner reminded him that I know what I am doing.

 

[1loudsuv]

You need to be very carefull with those modern aluminum head and block engines. There is no space for errors like the old cast iron ones.

I have 10 years auto mechanic experience and I will say this statement is true, I wasnt paying attention the other day while tourqing rocker arms with a digital torque wrench it was beeping away but I kept going and stripped the thread... just added another half hour of labor

 

[Garage_Mahal]

You are a fool if you tighten by feel on light metal. The difference in feel between "tight enough" and "pulling the threads" is minuscule. Steel on steel in non critical areas? Go for it.

 

[DHS]

I usually go by feel, but that has got me in trouble before, I still only use a torque wrench when I am assembling a engine (heads, bearings), everything else is by feel. I work on my own stuff so if I break it its my baby.

 

[Elroy]

Are you qualified to sign your name in one of those logbooks, Elroy?

Does that mean you can fix a round bailer with out a torque wrench?

 

[MisterCMK]

When a tractor craps out, the farmer pulls off the road and waits for some more baling wire. When an airplane has a problem, there's nowhere to pull off and wait. If that happens to be over the North Atlantic at 5am, with a heavy sea, some people are going to die that morning. That's why.

Aircraft structures are some of the most heavily stressed structures on the planet. They have to be, if they are to fly. As a consequence, the margin for error in their maintenance is minimal, unlike a tractor. They must be continually inspected with a fine-tooth comb, to find problems BEFORE they turn into emergencies. The concept of maintenance is something farmers don't seem to grasp, if the number of guys lined up at the parts counter with panicked looks during planting and harvesting seasons are any indication.

Have you ever even been near a farm during harvest or planting? It is quite apparent that you have not.

 

[69lm69gp]

I typically use the universal torque spec "tighten until the bolt breaks , then back off a 1/4 turn".

It works for me but then I don't work on aircraft.

BTW don't aircraft use a fair amount aluminum fasteners? I think that would be a game changer as far a torgue vs feel.

 

[Merkava_4]

If everything is supposed to be torqued using a torque wrench, what are combination, box end, and 30/60 angle wrenches for?

 

[garfunkle24]

If everything is supposed to be torqued using a torque wrench, what are combination, box end, and 30/60 angle wrenches for?

More wrenches to polish!

JK.

 

[Merkava_4]

I used to watch a guy at the Toyota dealer tighten up drain plugs. Granted, Toyota uses crush washers, but this guy would tighten the drain plug down with a 14mm combination wrench - take the wrench off the drain plug - and then tighten the drain plug again about a half a dozen more times. Keep in mind though, the drain plug never rotated a single millimeter from the first time he tightened it down.

 

[A_Pmech]

Does that mean you can fix a round bailer with out a torque wrench?

Yes. I have worked on the largest round baler Vermeer makes.

Diesel injection pumps too.

Neither of which are particularly stressed structures, beyond their own built-in design flaws. Mainly around the tongue area of the current models. They tend to suffer fatigue fractures there due to poor weldment design and threaded fastener location, something even the factory admits.

The failure of said structure would not kill hundreds of people. Nor would a round baler be likely to crash in downtown St. Louis on takeoff, due to the failure of a single bolted connection.

 

[walrus]

Does that mean you can fix a round bailer with out a torque wrench?

Of course you can, you can fix a plane without one also. The point is what happens if it fails because you didn't use one? In the farmers case, he's POed and his crop doesn't come in, he may go bankrupt. You suppose insurance companies would be lining up if the round baler broke? would they be checking to see how deep your pockets were?. Liability in todays world is a little different for airplane mechanics than round baler mechanics

 

[A_Pmech]

Liability in todays world is a little different for airplane mechanics than round baler mechanics

Well said and very true.

Liability insurance for an FBO or repair station makes a doctor's malpractice insurance look like Miss Nancy's Romper Room.




Some people wonder, why do they get on an airplane, with .040" of aluminum between the pressurized cabin and a soon-to-be near-vacuum. Then, allow themselves to be moved at near sonic speeds by equipment that has a definite service life, 9 miles above the earth's surface, completely out of the control loop?

Proper maintenance.

Airplane crashes make the headlines because they are an exceedingly rare event. If they were a common event, like car crashes, or had the same mechanical trouble as the average round baler, nobody in their right mind would set foot on an airliner.

If automobiles were taken care of the same way airplanes are, we'd all be driving '57 Chevys. Many examples of the commercial aircraft fleet are over 30 years old and they fly 10 hours or more a day. (The equivalent of driving a car 600 miles or more a day.) The US Air Force is still flying airplanes in combat that were flown by the current pilot's grandfathers.

I wonder how many farmers are running their grandfather's round baler? I wonder how many of those round balers are in the same condition as when they left the factory? That is the definition of "maintenance" in the airplane mechanic's world. -as good as the day it left the factory. That is the standard to which we are held.

 

[Elroy]

And when the caster wheel in the cargo bay floor comes loose you got to use the same calibrated and certified torque wrench used on the nose gear

Get off it cause Elroy isn't buying it

 

[rsanter]

if I am doing engine, trans, or rear end internals I am using a TW. valve covers, oil pans, intakes and such are fine with the feel by hand.

generally the suspension parts are very tight and brake stuff is just 'tight enough'

we had a farm and a tractor
lots of stuff is done by feel. open the engine and its all done with a TW.

dealt with a bunch of race and HP engines with aluminum heads and stuff. we always used studs on everything including header flanges so I have never pulled the threads in any aluminum heads

bob

 

[A_Pmech]

And when the caster wheel in the cargo bay floor comes loose you got to use the same calibrated and certified torque wrench used on the nose gear

Get off it cause Elroy isn't buying it

If there is a torque specified in the service manual, then yes. We're required to use that information and use calibrated equipment that is within it's certification period.

A good joke involves the fasteners that hold the toilet valve and toilet valve seal to the bowl. If they fail on a European transatlantic crossing, the airplane will lose cabin pressure out the toilet. Engine bleed air may not be sufficient to counteract the loss, which would cause the O2 masks to drop as the cabin decompressed. The airplane must then descend to below 12,000 feet, so that the passengers can breathe, as the O2 masks do not supply an extended amount of Oxygen.

Descending to 12,000' shortens the range of the airplane, which means in some cases the airplane no longer has sufficient fuel to make it's primary landing. Thus, an emergency landing must be made at an alternate airport and a second airplane dispatched to continue the flight.

Those $2 threaded fasteners, installed at an improper torque? They just cost the airline about a half a million dollars, assuming nobody got hurt.

If there is no torque specified in the service manual, then mechanic's discretion and the chart of standard fastener torques apply.

 

[WHT]

Well said and very true.

Liability insurance for an FBO or repair station makes a doctor's malpractice insurance look like Miss Nancy's Romper Room.




Some people wonder, why do they get on an airplane, with .040" of aluminum between the pressurized cabin and a soon-to-be near-vacuum. Then, allow themselves to be moved at near sonic speeds by equipment that has a definite service life, 9 miles above the earth's surface, completely out of the control loop?

Proper maintenance.

Airplane crashes make the headlines because they are an exceedingly rare event. If they were a common event, like car crashes, or had the same mechanical trouble as the average round baler, nobody in their right mind would set foot on an airliner.

If automobiles were taken care of the same way airplanes are, we'd all be driving '57 Chevys. Many examples of the commercial aircraft fleet are over 30 years old and they fly 10 hours or more a day. (The equivalent of driving a car 600 miles or more a day.) The US Air Force is still flying airplanes in combat that were flown by the current pilot's grandfathers.

I wonder how many farmers are running their grandfather's round baler? I wonder how many of those round balers are in the same condition as when they left the factory? That is the definition of "maintenance" in the airplane mechanic's world. -as good as the day it left the factory. That is the standard to which we are held.

Most people understand and appreciate the training required for A&P certification. And, I would have thought, everyone would realize that you don't guess when lives are at stake.

However, you are trying to have rational discussions with someone who refers to himself as "Elroy" and doesn't understand the difference between a round baler and an airplane (not sure about a round bailer) and another who doesn't know why open end wrenches do not use a V notch instead of a curved surface. Doubt if either discussion will be very productive.

 

[kiall1987]

Most people understand and appreciate the training required for A&P certification. And, I would have thought, everyone would realize that you don't guess when lives are at stake.

However, you are trying to have rational discussions with someone who refers to himself as "Elroy" and doesn't understand the difference between a round baler and an airplane (not sure about a round bailer) and another who doesn't know why open end wrenches do not use a V notch instead of a curved surface. Doubt if either discussion will be very productive.

So do you check your torque wrench every time your set it with a certified machine ? I dont think so , i know your problary going to argue anyway , theirs doing job properaly and their the factor of actually finishing the job too...