Craftsman Torque Wrench - Help Me Decide!

[michigan]

Gary, I agree that consistency is important, but can you tell me what is "too loose" or "too tight"?
My manual says 15 ft/lbs for my triple clamp pinch bolts, but is that with a new fastener, or just a clean, dry fastener? Can I re-use my old fastener if I chase the threads with a tap and die? This is a steel fastener in an aluminum triple clamp, so I'd like to use some anti-sieze. How does this affect my torque value? Or what if I use loctite? How does the lubricity of this product affect my torque value? If I use nothing, what is the error caused by friction? Torque produces tension on the fastener, and it is affected greatly by friction, wouldn't you agree?
I've been told that I should reduce the torque value by 40% if I'm using anti-sieze... but is this on a new fastener, or my old fastener?
15ft/lbs minus 40% leaves me at 9 ft/lbs of applied torque (as indicated by my new sears wrench) on a lubricated fastener holding my forks to the front of my kx500 while I'm pounding through sand whoops. Does that sound good to you?

As an engineer by trade, I think about questions like these. I don't have the answers. Do you?

 

[Gary B.]

Michigan- all I'm saying is stripped, distorted, or broken=too tight, part rubbing/movement or falling off= too loose. Sheesh! You engineer guys must lay awake nights worrying about stuff like this. All I think the average person needs is the happy medium. Alot of people don't realize how much of a difference there is in tightening a 1/4" bolt with a 4" long wrench or a 8" long wrench. When it comes to tightening something like a cylinder head it's too easy to tighten bolts unevenly and distort parts. At least with a torque wrench all the fasteners are equal.

 

[James]

Originally posted by michigan
My manual says 15 ft/lbs for my triple clamp pinch bolts, but is that with a new fastener, or just a clean, dry fastener? Can I re-use my old fastener if I chase the threads with a tap and die? This is a steel fastener in an aluminum triple clamp, so I'd like to use some anti-sieze. How does this affect my torque value? Or what if I use loctite? How does the lubricity of this product affect my torque value? If I use nothing, what is the error caused by friction? Torque produces tension on the fastener, and it is affected greatly by friction, wouldn't you agree?
I've been told that I should reduce the torque value by 40% if I'm using anti-sieze... but is this on a new fastener, or my old fastener?
15ft/lbs minus 40% leaves me at 9 ft/lbs of applied torque (as indicated by my new sears wrench) on a lubricated fastener holding my forks to the front of my kx500 while I'm pounding through sand whoops. Does that sound good to you?

As an engineer by trade, I think about questions like these. I don't have the answers. Do you?

Your manual will generally tell you whether the fastener should be lubricated or dry. Generally they are dry. Generally they are also re-used as manufacturers (and their engineers) don't always tell you to use new fasteners each time. Why would you chase it with a tap and die? They aren't crimped in the triple clamps.

Information on the effect of lubricants/anti-seize/locking compund is available and if you use this stuff on fasteners that don't require it (as in not specified) in the manual, then you are reliant on the info you find. Most specified torque values are the median of a range of acceptable torque values so in MOST cases the torque doesn't need to be exact. SO 15lbs is just right, 13,14,16,17 is probably ok. Finally, if 40% is the correct adjustment to make to your pinch bolts for the lubricant used, then 9lbs on the lubed bolt is going to apply the same clamping force as 15lbs on a dry one. I would trust it so long as I did the other thing my manual tells me, "check fasteners for tightness."

Are you a mechanical engineer by trade because this stuff should be obvious.

 

[cr25096er]

where can i get a snap on torque o meter beam torque wrence? i was tightening a bolt n it like snapped n locked up. i han hear something bouncing around in there when i shake the wrence now.

 

[cr25096er]

where can i get a snap on torque o meter beam torque wrence serviced? i was tightening a bolt n it like snapped n locked up. i han hear something bouncing around in there when i shake the wrence now.

 

[Gary B.]

cr25096er-you need to take the wrench back to a Snap-On dealer in you area. Check the Yellow Pages or the local auto repair shop.

 

[michigan]

Gary,
Great response. That method would probably work for 99% of applications 99% of the time, regardless of the condition of the fastener or what luricant it has been treated with.

James,
Thanks for taking the time to type all those words.

-Ray

 

[James]

No problem. I take great pleasure in talking to the wall.

 

[bmonnig]

LOL...

James, I noticed that too, but it's still pretty funny to see. :)

Brandon

 

[cr-man]

Spend the money buy a snap-on or Mac! Craftsman torque wrenches leave a lot to be desired. My Dad bought the best sears had and it fell apart on the first try took it back got another one same thing. Junk