You can buy 2.75 OD x .120 wall tubing from DX Engineering. The inside
diameter will be 2.510 giving you ten thousandths clearance to over sleeve the
joints.
http://www.dxengineering.com/parts/dxe-at1316
73...Stan, K5GO
Sent from my iPad
> On Sep 15, 2014, at 1:02 AM, "L L bahr " <pulsarxp@embarqmail.com> wrote:
>
>
> I'm slowly building up a 40 meter Moxon Beam and the boom needs to be
> somewhere between 24 and 27 foot long depending on the article used to build
> it. The boom has me stuck. As all of you know, most aluminum is sold in 6
> foot lengths for shipping purposes. That means the tubes need to be
> connected. I'm at the point where I need to determine what I am going to use
> for boom material and how to connect the segments.
>
> I have some 2 1/2 inch aluminum tubing I bought surplus many years ago. The
> stuff has a wall thickness of around 1/16th inch thick and is hard aluminum,
> probably 6061 alloy. I've got plenty of it in 6 foot lengths. It's gorgeous
> looking tubing and I initially figured and wanted to use it for my boom
> material. However, I have been racking my brain out trying to figure out how
> to join the sections. (The inside diameter is around 2 3/8th inches ID.) I
> tried 2 inch schedule 40 pipe and it is a tad too large in diameter to fit
> into this 2 1/2 inch OD tubing with an approximate 2-3/8 inch ID. (I thought
> maybe sanding down some schedule 40 aluminum pipe but would I get it to
> really work?) I thought maybe turning some oak down to a diameter to fit
> inside this tubing, I have hunted high and low for some aluminum stock to
> either snuggly fit inside or outside this pipe with no success. If I buy 3
> inch OD tubing, it will have an ID of 2-3/4 inches. I even thought of
> slicing th
e
> ends open in the form of a cross in some 3 inch tubing and then use hose
> clamps to secure things, but then the pipe would only be tight on one end of
> the joining pipe. I thought maybe of slicing the 3 inch pipe open along it's
> length and then use hose clamps to pull it tight and together again around my
> existing pipe. The bottom line is I have not been able to figure out how to
> use my tubing satisfactorily. I'm now starting to think maybe my tubing is
> not the answer for my needed boom material. That really seems like a big
> waste as I know if I bought this tubing new it would run big bucks. A 40
> meter Moxon is no small antenna so the boom material needs to be decent and
> adequate for my purpose.
>
> That said, am I missing something here? Anyone on here who could get me on
> a proper path? I need to either find of way to use my existing 6 foot
> lengths of 2-1/2 OD tubing with a 2-3/8th inch ID or move on to something
> else for the boom. I'd sure appreciate hearing from you experts as my
> quandary has been bugging me for weeks now. Right now I am just spinning my
> wheels going nowhere. I might add, I do not have a machine shop at my QTH.
> I thought I would try one last time to figure out how to use my tubing before
> I give up on that idea by asking you guys for advice. Any and all comments
> would really be appreciated.
>
> Lee, w0vt
> Houston
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|