- Joined
- Oct 9, 2013
- Messages
- 4
Hello all,
I have been pretty quiet on the forums and this will be my first project posting.
I thought my latest project, a tower extension for ham radio antenna tower, might be of interest, in terms of material properties and selection, engineering design and fabrication. However, there is no lathe or mill work involved however, mostly fit-up, weld up and general fab.
The project will be to build a 32 foot tower base for a 54 foot crank up tower purchased from Tashjian Towers. The crank up tower, 19 3/4 inches at the base, is 21 feet collapsed and 54 feet extended in three sections. It is designed to attach to a concrete base and weighs 600 pounds.
Instead I'm going to add 30 feet ( for a total height of 84 feet extended), attaching that base to a 30 foot extension and that is this project.
I already have a 51 foot tower in place that tilts on a hinge I fabbed from old tractor parts.
The lower 8 foot section of that, fabbed from 3x3x3/8 angle, will be re-used as part of the 32 foot new base build.
I will also re-use the hinge, beefing that up for the added weight and wind load.
The overall design must withstand the 80MPH (1.5 times that for safety) gusting limit for my area ( 26 miles east of Seattle).
The reality is, in our Cascade foot hills I will never see 80MPH gusts, but that is the engineering standard.
The 54 foot Tashjian Tower is designed for 80mph gusts of 3 second duration at its full height. At full collapsed it can withstand much more.
I will post a picture of the current base for reference, here we go.............must be done by Sept.
I have been pretty quiet on the forums and this will be my first project posting.
I thought my latest project, a tower extension for ham radio antenna tower, might be of interest, in terms of material properties and selection, engineering design and fabrication. However, there is no lathe or mill work involved however, mostly fit-up, weld up and general fab.
The project will be to build a 32 foot tower base for a 54 foot crank up tower purchased from Tashjian Towers. The crank up tower, 19 3/4 inches at the base, is 21 feet collapsed and 54 feet extended in three sections. It is designed to attach to a concrete base and weighs 600 pounds.
Instead I'm going to add 30 feet ( for a total height of 84 feet extended), attaching that base to a 30 foot extension and that is this project.
I already have a 51 foot tower in place that tilts on a hinge I fabbed from old tractor parts.
The lower 8 foot section of that, fabbed from 3x3x3/8 angle, will be re-used as part of the 32 foot new base build.
I will also re-use the hinge, beefing that up for the added weight and wind load.
The overall design must withstand the 80MPH (1.5 times that for safety) gusting limit for my area ( 26 miles east of Seattle).
The reality is, in our Cascade foot hills I will never see 80MPH gusts, but that is the engineering standard.
The 54 foot Tashjian Tower is designed for 80mph gusts of 3 second duration at its full height. At full collapsed it can withstand much more.
I will post a picture of the current base for reference, here we go.............must be done by Sept.