buying suggestions torque wrenches

[sbrguy]

I am a professional Porsche tech.  I have a $300 dollar 1/4  Matco torque wrench, a 3/8 snap on at 400 bucks, and a 1/2 snap on at around 500 bucks.  I wouldn't  consider buying a harbor freight torque wrench even for home use because the quality of any of their house brands is shit. Home Depot has husky brand which is about even with the craftsman stuff and you may want to check them out.  Porsche sends us special application tools that are required for a specific job. This past week they sent us this fancy $2500 torque wrench that will be used on the upcoming Panamera sedan. It is for tightening aluminum bolts and calibrated only for that.  Apparently the newest thing is to use aluminum fasteners instead of steel to shave weight. 

wow alum bolts into a ti base, talk about a situation that is begging for overtorquing... the only thing i can think of better is magnesium bolts into carbon fiber threads.. oh wait that is the entire bicycle industry there.

thanks for some of the suggestions guys, i have called the local home depot and they stock the husky stuff and from what it seems its a good value.

i also looked into the cdi brand, and will give them a call tomorrow, from what it sounds like its lieterally 1/2 between craftsman and snapon in pricing.  sounds like it might be all the quality of the snap on but less of a label markup, but i will find out if its actually the same tool or not.

i know in the bicycle industry the lower inch lb torque wrenches are being used by all reputable bike shops as everything on high end bikes now has torque ratings of things like 1 or 2 nm or a few inch pounds and such.. they are selling for well in excess of 150$.

figure i better start learing how to do simple stuff on the bike the correct way from the beginning from chaning the oil, tightening the chain, etc and actually use the correct torque specs on things to hopefully lessen the chance of any screw ups.

thanks for the advice guys, got a question seems like in order to work on a bike any sort even small things easy things you need to buy tons of tools. 

is this the second "cost" of modding? ie, the tool acquiring part?

got a question, i noticed on a 620 most of the bolts including the rear axle are tops at 86 nm what bolts "require" the use of the 1/2 inch bit and the larger values?

thanks.

[Ddan]

is this the second "cost" of modding? ie, the tool acquiring part?



thanks.

You mean the second 'benefit', don't you?   

[mitt]

You can see the performance of the $80 craftsman wrenches here:

http://sites.google.com/site/mittelstadtc/Home/file1/torquewrenchcals.pdf?attredirects=0

It is a pdf I made after having my personal wrenches calibration checked in our metrology lab at work.

I actually broke my first craftsman 3/8" wrench.  Motor oil got on the locking ring on the handle, and made it brittle.  The next time I used it, the ring broke.  I am not satisfied with the craftsman plastic handle design with printed numbers.  The numbers on my wrenches are becoming very hard to read due to wear.  I would go for an all steel construction with stamped numbers next time.  And, since I have access to a metrology lab, I would buy a cheap wrench, then cal it myself.

mitt

[Speeddog]

----------snip-------------

got a question, i noticed on a 620 most of the bolts including the rear axle are tops at 86 nm what bolts "require" the use of the 1/2 inch bit and the larger values?

thanks.

From memory, the clutch hub nut, primary gear nut, and the flywheel nut are all above 86 n-m.
Not stuff you'll be dealing with in normal servicing on a 620, though.

[sbrguy]

From memory, the clutch hub nut, primary gear nut, and the flywheel nut are all above 86 n-m.
Not stuff you'll be dealing with in normal servicing on a 620, though.

you are right, there is no F-ing way i'm going to touch stuff that difficult.  especially since its a wet clutch.

i'm talkign simpel stuff liek chain adjustment and simple checking torque specs on bolts on teh bike, etc...i'm not going to touch the internals of the engine, i'll leave that up to you pros.

saw those specs in the manual the other night noticed they are really high up there like you said, but like you said they are really the only ones that are that high.

[gage]

you are right, there is no F-ing way i'm going to touch stuff that difficult.  especially since its a wet clutch.

i'm talkign simpel stuff liek chain adjustment and simple checking torque specs on bolts on teh bike, etc...i'm not going to touch the internals of the engine, i'll leave that up to you pros.

saw those specs in the manual the other night noticed they are really high up there like you said, but like you said they are really the only ones that are that high.

That is where everyone starts 

Before you know you'll be adjusting valve clearances and taking an engine apart to have the crankshaft polished.

[ducatiz]

you are right, there is no F-ing way i'm going to touch stuff that difficult.  especially since its a wet clutch.

i'm talkign simpel stuff liek chain adjustment and simple checking torque specs on bolts on teh bike, etc...i'm not going to touch the internals of the engine, i'll leave that up to you pros.

saw those specs in the manual the other night noticed they are really high up there like you said, but like you said they are really the only ones that are that high.

i got an inch/lb and nm wrench in 3/8" that's about a foot long for most small stuff like you are describing.  if you need something bigger later, then you can get it.  i use the small one the most just because it is so portable.

[clubhousemotorsports]

I own about 7 different torque wrenches
2 beam type- cheap sears
2  snap on torqometer torque wrenches
1 3/8 5-75 ftlb snap on clicker
1  1/2"  TQ series snap on
1  3/8 snap on tech angle
each one has a  purpose and they all are useful.

The techangle was the most expensive and gets used the least, it is overkill for most jobs.
The 3/8"  5-75ftlb unit gets used the most and has to get re-calibrated the most. $75.00 last time it was done .
The TQ series is nice because for a click type there is no preload on the spring to sack out the spring and change the calibration.
The torqometers are nice quality pieces for dial torque wrenches
The sears beam wrenches almost never go out of adjustment and are axe simple, no bling though and hard to read especially upside down.

remember to pick the range carefully when you are at the edge of the torque wrenches range the accuracy gets worse the close to the edge you get.

[sbrguy]

how is it that the standard cheap sears beam wrench stays accurate?  wtf?

[clubhousemotorsports]

Simple it is not the beam type that is the problem, it is the springs that sag out on a clicker type. If you have a spring loaded torque wrench and you leave spring pressure on the spring (pre-load) over time the spring loses its rate. When this happens the accuracy of the torque wrench gets off, this is why you do not leave a clicker/spring type torque wrench "wound up".

Beam types simply have no spring tension on them until you are using them, this allows them to keep their accuracy.  The inherent inaccuracy of this type is not in the tool but in the user. It is hard to be adding torque and getting your eye to line up the pointer with the beam, the beam types also have a floating type of handle that needs to be kept centered (floating) for accurate torque.

Clicker torque wrenches are the easiest to use but must be maintained (calibrated) more often last time mine was done it was almost 10 ftlbs off.

TQ series do not keep the spring under tension so should be less prone to need re-calibration same with the electronic strain gauge type, only time will tell.

[corey]

Stupid floating handle... You learn something every day i guess...
Looks like all MY bolts are over-torqued... Anyone else?

[mitt]

I am surprised a chinese knockoff digital wrench with a strain gauge hasn't come out yet.  It would be pretty simple to do really, and probably superior to the click from a calibration hold standpoint.

mitt

[clubhousemotorsports]

I am too I try not to think of what my snap on cost me.

Hey chinese gotta torque things too!

[ducatiz]

Hey chinese gotta torque things too!

that's what she said.

[corey]

So.. For a weekend wrencher, who isn't going to be going anywhere near the motor/gearbox, aside from the front sprocket... would a torque wrench (i'm looking at the CDI) with a range 10nm-60nm be a sufficient range?

(i dont have my service manual with me)