Satellite mast aluminium tubing sizes. What will fit into what?

[Bordonbert]

Hi guys. This will be a straightforward answer for anyone who works with aluminium tubing on a regular basis. I don't I'm afraid hence my asking here. I know professionals would want to consider the time aspect but that isn't a concern for myself. And price is not critical but "silly price" leaves a bad taste in the mouth.

I have an installation based on 1.25" (32mm on paper, according to metal suppliers 31.75mm) 16SWG aluminium tubing. I would like to extend that by just a couple of feet. With an extra length of the same size tubing and a coupler that is no problem. However... I found that couplers for 1", 1.5" and 2" are commonplace and pretty cheap. 1.25" couplers are like hen's teeth and when you can find one they ask ridiculous prices, and I mean £35 and upwards. I did think that I could maybe just sleeve the joint with another piece of slightly bigger tubing using rivets to hold things in place and looked up the tube dimensions.

I can get 1.375" ( that's 1.3/8" or 34.9mm) tubing in 16SWG. 16SWG is 1.626mm meaning that this tubing should have in ID of 31.74mm. My question is, the idea of sliding the 1.1/4" inside the 1.3/8" tubing seems to be possible given the decimal rounding off of some of those sizes but does this actually work in practice?

Failing that, is there somewhere I can get a 1.25"-1.25" coupler at a reasonable price? Or, even better, is there a way to make a stiff enough joint with two tubes of the same thickness. Maybe slotting the inner tube along its length to allow some compression would work. A hacksaw blade thickness may be all that is needed. As I said I do propose to rivet the two together at both ends. Or is there a 1.25" extension tube available with a narrowed end to fit inside tube of the same size?

 

[UNG]

What is the tube you are trying to extend fixed to

It may be more cost effective to go for a larger diameter tube and some new U bolts asuming that the existing tube is fixing to a T & K bracket or a chimney plate or something similar

 

[Bordonbert]

It's a short cranked mast to fit around the soffit fixed firmly to the wall with two brackets. It only clears the height of the soffit by about 18". I could get the dish on there but I wanted to give it a few more feet as it has to point back over the pitch of the roof. It's on the northern wall of a terraced house as the south facing wall is masked by tall trees and is unusable. The trees belong to a wilderness park and they won't consider trimming them. That location is the only one available as it points through a good sized gap in those trees which mask every other option.

 

[UNG]

The problem with extending your existing pole will be the additional wind loading ( bending force ) you incur on such a small diameter pole so I would look at a new pole and depending on what wall bracket you have replacing that as well if it will not take a larger diameter pole and or larger U bolts

I would suggest you have a look at these sites

Poles and masts – A.T.V. Poles, Brackets, Clamps & Aerials

www.aerialsandtv.com

Satellite Superstore UK. Wall Mounts, Ground Stands, Heavy duty satellite dish wall mounts. High quality. Starlink

Satellite dish wall mounts and ground stands for satellite dishes, Pole adapters, Masts, Coach bolts and plugs, clamps, short and long poles. For DIY or installers, Starlink Pole Adapter. Above the gutter wall mounts, heavy duty and budget wall mounts. Stands for 1.0m, 1.2m, 1.8m, 2.3m and...

www.satellitesuperstore.com

I would look to use a 2" / 50mm pole to keep the pole flex to a minimum in high winds to maintain good satellite reception it doesn't take a lot of flexing to lose good reception

 

[Bordonbert]

I realise the wind force will increase as you lift the dish of course. I had hoped that, as it still sits well below the roof crest and we are surrounded by much taller trees, it would not be too great. Mounting brackets are flat faced into the brickwork with 4xM8 rawlbolts on each and they will accommodate larger poles. I think you are probably right, a pole upgrade might be in order as the most reliable and cost effective option. Thanks for the help Ung, it's appreciated.

 

[UNG]

From past experience of installing satellite comms and radio data comms kit sleeving / extending small diameter aluminium poles is never really an option especially where the aluminium has weathered and become brittle, sometimes you can double pole to extend but for sat dish mounting my preference is 1.75" or 2" pole to reduce the flexing under wind load as previously mentioned