I use a nut driver when building an antenna, carefully installing each
section of tubing so that it sticks out the designed length. Then I go
back over them with a 1/4" socket wrench and tighten them a little more. I
use the highest quality, strongest clamp hose clamp that McMaster-Carr
sells and it has been years since I stripped one. This is not something
that you want too loose for the reasons AA4NU mentioned below. I like the
way hose clamps clamp the tubing around the whole circumference instead of
the small surface that is held by a rivet. For me it is also easier to
build by setting the tubing lengths and clamping. I am not sure how I
accurately I could set tube length and drill it for a rivet without the
tubing moving. The down side to hose clamps is if your antenna is in a
corrosive environment the stainless steel band will cause the aluminum
tubing to corrode and expand. Over time this will break the hose clamps.
John KK9A aka P40A
To: Doug Renwick <ve5ra@sasktel.net>
Subject: Re: [TowerTalk] Shorty Forty Hose Clamp thread
From: Billy Cox <aa4nu@comcast.net>
Date: Tue, 11 Aug 2015 14:50:19 +0000 (UTC)
Good Morning All,
And despite a rather rude comment from Doug sent to directly to
my email, here is a bit more information to HELP others perhaps.
Again, we are using clamp products in applications that may not
represent their common usage. So your mileage may vary, WFWL.
Our website shows only the more popular common designs, not the
special designs where the focus is on specific connection needs.
Doug's "simple" install method does not take into consideration
factors such as connection vibration nor repeated thermal cycling.
Let's say for example, you must hire a crane to lift and install
your new yagi. Once up there, you cannot reach the elements. If
something 'comes loose', it will be additional time and expense.
Now we have to make a critical decision:
A. Use the "simple" method outlined below that does not follow the
manufacturers instructions. It might work well, or it might not.
B. Use the method and torque settings from the manufacturer and
know you have followed the suggested install specifications.
Would that be over engineering, or simply using common sense given
risk of failure and related costs to repair the loose element(s)?
73 de Billy, AA4NU
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