Ramon, You must be working with old rusty bolts to get more torque to remove. This does not happen with clean, freshly torqued hardware. Think of the screw/thread as two ramps sliding together and you can visualize the physics involved. Loosening involves overcoming friction under the head and against the threads. When loosening, you are unloading the forces holding the threads together...this is less friction, less torque than driving the threads together. I will try your experiment, but my experience is less torque to loosen. ----Rainer -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Dehoyos, Ramon Sent: Friday, May 06, 2005 10:23 AM To: [log in to unmask] Subject: Re: [TN] Torque Hi Victor: The untorqueing force will be higher. When the hardware is torqued, it starts from being loose and as it is tighten it gets hot due to friction and the heat makes the molecules from both surfaces soft so it slides. Once the hardware is cold, the initial force to break the cold bond has to be higher. This is ignoring the oxidation between the adjacent materials due to time and moisture. Some torque tools work in either direction. Find one of them and set the tool to a torque in the midrange and tighten a bolt. Reverse the tool and try to release it and you will see that it takes more torque. Make sure that your hand is placed in the same area on the tool and the pull is perpendicular to the bar. Regards, Ramon -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Victor G. Hernandez Sent: Thursday, May 05, 2005 5:25 PM To: [log in to unmask] Subject: [TN] Torque Fellow TechNetters: Can someone share their experience with the topic of TORQUE. How is the torque valve of hardware differ from the value of Un-torqueing that same hardware. Is the torque valve higher than the un torque value or vice versa. Power FETs can be damaged when the plastic package exhibits a hole where the bolt is inserted. Not the typical TO220 or TO66 plastic style. Victor, --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------