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#1
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fiberglass mast question
Anyone have suggestions on a method I might try to "twist" and collapse some sections of my telescoping fiberglass mast? I put it up several days ago with perhaps a bit too much "vigor" in making sure it would not collapse on its own and now that I want to stow it away there are a couple of sections I can not unlock. My grip is good, but the sections are really tight. I hate to use something mechanical for fear of cracking the fiberglass and I hate to use a lubricant since the locking requires friction. Thoughts ? Ed K7AAT |
#2
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fiberglass mast question
Ed wrote:
Anyone have suggestions on a method I might try to "twist" and collapse some sections of my telescoping fiberglass mast? I put it up several days ago with perhaps a bit too much "vigor" in making sure it would not collapse on its own and now that I want to stow it away there are a couple of sections I can not unlock. My grip is good, but the sections are really tight. I hate to use something mechanical for fear of cracking the fiberglass and I hate to use a lubricant since the locking requires friction. Thoughts ? Ed K7AAT ====== Immerse outer end (only)in hot water. Hopefully it will expand slightly ,but not the inner mast part . Alternatively cover outer end with insulation material and 'cool' inner mast tube with evaporating CO2 'ice' hopefully causing it to shrink slightly. Of course success is not guaranteed but worth trying .....at least it is non-destructive. Frank GM0CSZ / KN6WH |
#3
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fiberglass mast question
On 27 Aug 2008 19:04:14 GMT, Ed
wrote: Anyone have suggestions on a method I might try to "twist" and collapse some sections of my telescoping fiberglass mast? I put it up several days ago with perhaps a bit too much "vigor" in making sure it would not collapse on its own and now that I want to stow it away there are a couple of sections I can not unlock. My grip is good, but the sections are really tight. I hate to use something mechanical for fear of cracking the fiberglass and I hate to use a lubricant since the locking requires friction. Let me guess. You extended the pole when the air temperature was cold and are now trying to collapse it when the air temperature is hot? The coefficient of thermal expansion is about the same as glass or 1.1x10^-5 inch/inch/F which is enough to expand the inner tubing into the outer sleeve almost permanently. After a few field days of having exactly the same problem, I sorta learned my lesson. The easiest is to wait until it cools down at night. You can also splash cold water on the joints, which might help. If you want to prevent the problem in the future, I found that ordinary Ivory soap smeared on the joint, makes a decent lube that will not cause premature collapse. If you apply too much, just wash it off. Also, do NOT beat on the ends in an attempt to release the seized joint. The twist type telescoping locks will just lock even harder. If brute force is your forte, you might try a rubber pipe strap wrench as used to remove an automobile spin on oil filter. Wrap the strap around a few times and put something under the gripper teeth to distribute the force. I've never tried this but it seems like it might work. Also, make sure you're turning in the correct direction. I did that once with a window washer pole with predictable results and embarrassment. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#4
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fiberglass mast question
Jeff Liebermann wrote in
: If brute force is your forte, you might try a rubber pipe strap wrench as used to remove an automobile spin on oil filter. Wrap the strap around a few times and put something under the gripper teeth to distribute the force. I've never tried this but it seems like it might work. Those strap wrenches work pretty well, Jeff. - 73 de Mike N3LI - |
#5
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fiberglass mast question
On Aug 28, 3:52*am, Mike Coslo wrote:
Jeff Liebermann wrote : If brute force is your forte, you might try a rubber pipe strap wrench as used to remove an automobile spin on oil filter. *Wrap the strap around a few times and put something under the gripper teeth to distribute the force. *I've never tried this but it seems like it might work. Those strap wrenches work pretty well, Jeff. * * * * - 73 de Mike N3LI - You could try holding the pole vertical and let the whole lot drop a few feet so that the base falls onto a hard surface (assuming it has some sort of bump cap on the base). This inertia and rapid deceleration usually releases even the most stubborn joints. UKM |
#6
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fiberglass mast question
If brute force is your forte, you might try a rubber pipe strap wrench as used to remove an automobile spin on oil filter. *Wrap the strap around a few times and put something under the gripper teeth to distribute the force. *I've never tried this but it seems like it might work. Those strap wrenches work pretty well, Jeff. * * * * - 73 de Mike N3LI - You could try holding the pole vertical and let the whole lot drop a few feet so that the base falls onto a hard surface (assuming it has some sort of bump cap on the base). This inertia and rapid deceleration usually releases even the most stubborn joints. I have used these poles a lot, and the 'bump' method usually works for me. Start on grass to cushion the blow, and gradually increase the impact force until the joint comes free. Twisting usually does not work, though a little soapy water and heating might help. Be very careful about using any kind of wrench or vice jaws, as these thin-walled poles are VERY vulnerable to crushing. On the other hand, I've never damaged one by end-on impact. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek |
#7
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fiberglass mast question
On Thu, 28 Aug 2008 12:07:01 +0100, Ian White GM3SEK
wrote: On the other hand, I've never damaged one by end-on impact. I have. It split the tubing just below the locking area. The problem is that there are many types of locking mechanisms. You need to know what's inside and how it works before applying the traditional brute force. For example, some poles use external compression or cam type locking mechanisms: http://www.telescopingpoles.com/specs.html http://www.briarwoodproducts.com/newtools.htm These do not jam and will respond properly to the inertial hammer (brute force) disconnect method. However, they add width which is often undesireable. Internal locks, with expanding cores, cams, or wedges are a different story. To prevent collapse, most become tighter when loaded in compression, especiallyl those that take advantage of a slight conical taper in the tubing: http://www.google.com/patents?id=78duAAAAEBAJ http://www.google.com/patents?id=fvc5AAAAEBAJ http://www.google.com/patents?id=i2ZMAAAAEBAJ http://www.google.com/patents?id=_hMBAAAAEBAJ (Look at the drawings). Banging on these internal locks will jam them only worse. I couldn't find a picture of the inside of the common window washer fiberglass pole. It has partial threads molded into the fiberglass. 1/4 turn to lock. Bang on that design, and you'll split the tubing (like I did). -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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