Sorry, this post got LONG >>Phil said "Believing a torque wrench can have some serious consequences . i just believed one and set head torque...."<< OK I searched the web for this and didn't find a quick answer so I'll shoot from the hip and try to trust my memory. Torque is force times distance. It's the amount of rotating or twisting force that is created by applying a force perpendicular to an axis. The distance from the axis that the force is applied multiplies the force. If the torque specified for something like a 1/4 inch nut is 24 inch lbs and your wrench is 12 inches in length then you would only have to apply 2 lbs of force to the end of the wrench to achieve the 24 inch lbs of torque, that is really a very light push. 2lbs times 12inches =24 inch lbs. If you had a torque wrench that measured foot lbs and set it to 24 that would be 24 ft lbs which would be more than ten times the specified inch lbs specification, even pros have been known to make this mistake when hurried and inattentive. If you are torquing something big like a 7/8 inch spark plug in Continental that calls for 33 ft lbs then you would have to push 33 lbs against that little 12 in wrench. Most ft lb torque wrenches are around 16-18-to 24 inches long. If you are pushing on the end of an 18 inch wrench then 18 divided by 12 = 1.5, meaning that for every 1 lb of force that you apply to the end of the 18 inch wrench 1.5 lbs of torque is applied to the hypothetical spark plug; therefore to achieve 33 ft lbs of torque with a 18 inch long wrench you would only have to apply 22 lbs of force to the end of the wrench (33ft lbs divided by 1.5ft lbs = 22ft lbs). 22 lbs of force can easily be applied by one arm with a medium push without having to brace the other hand against anything. Think about it if you go the the gym and pick up a 20lb weight to add to your bar bell you wouldn't want to push much harder than that on your 18inch spark plug wrench. In the certified aircraft world A&P mechanics are required to use periodically calibrated torque wrenches, they keep them in a padded case like some sort of jewelry, and handle them like a fragile egg when in use. If a torque wrench is dropped or banged against something its calibration should be recertified before it is used again. In the experimental world use your best judgement do the math before you torque and have a good idea of how hard you should expect to have to push or pull on the wrench handle. If you suspect that your torque wrench is a liar and your arm isn't calibrated yet then measure your wrench length do a little math and hook a good accurate fishing scale around the end of the wrench and pull away on the fishing scale. Edward Spyker jesj69 (at) yahoo dot com
________________________________ From: Mark <markweg...@charter.net> To: 'phil brookman' <pjb1234...@yahoo.co.uk>; 'KRnet' <kr...@mylist.net> Sent: Monday, October 17, 2011 7:18 PM Subject: RE: KR> torque wrenches Racing practice is to use new fasteners when possible (studs, bolts, etc.) and measure stretch as a backup for torque. You are really trying to measure clamping force and stretch can be a better indicator of what you are getting with new studs and bolts of a known grade and quality. Just a thought Mark W. N952MW (res.) -----Original Message----- From: krnet-boun...@mylist.net [mailto:krnet-boun...@mylist.net] On Behalf Of phil brookman Sent: Monday, October 17, 2011 1:12 AM To: KRnet Subject: KR> torque wrenches Believing a torque wrench can have some serious consequences . i just believed one and set head torque.... phill ________________________________ From: M&C <aviato...@phreego.com> To: KRnet <kr...@mylist.net> Sent: Monday, October 17, 2011 5:20 AM Subject: Re: KR> Encapsulating I've heard you can mix rubbing achohal with it and the achohal will evaporate out after you have spread it. You might test that on something first. Mike Turner Edgewood N.M. ----- Original Message ----- From: John Backer To: KRnet Sent: Sunday, October 16, 2011 8:05 PM Subject: Re: KR> Encapsulating What are the current thoughts on how to thin epoxy to get a good flow? > > Dana Overall > > Have you tried heat? I have used a hair drier many times to get epoxy to flow. You might try some samples to see if it does what you would like. John Backer _______________________________________ Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html _______________________________________ Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html _______________________________________ Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html _______________________________________ Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html
