[TowerTalk] Crankup Tubular Tower Info

[Mike Newman]

My thanks for the replies to my queries. 

I've learn't a lot about how these masts are assembled.  I had the rope and pulley system figured out, but wasn't sure about the key, particularly how it was fastened to the tube.  The photos from the eBay site were very helpful.

I'd given away welding for two reasons 
1) damage to the zinc galvanizing on the tube, and 
2) more importantly, the unavoidable curvature which would develop from welding distortion.  The tubes would no longer be straight. 

The answer obviously is -- no welding. 

Being in a fairly windy locality on a coastline, I'm concerned about  both the lateral forces on the key and it's fastening to the tube, and  protection from corrosion.

I'd be grateful for some information on the size and spacing of the screws attaching the key, and of the size of the key itself.  If I make these too light or insufficient in number, then I could experience damage from rotation of the mast by winds.

Is the key galvanized, or has the whole assembly been hot-dip galvanized after assembly?

I've built the foundation, base, and the tilting arrangement, they're adequately sized.

Just have to get this project completed.

Thanks  de  MikeN   ZL1BNB