Tower base rebuild, something a little different

[Rover]

My tower is a little different than most, its a derick style that use a cantiliver mechanism to raise lower.
It's only 30 ft, but still a lot of weight on the winch that raises and lowers it. And the reason for the rebuild is my design flaw makin the pivot point to low, straining the winch. (This did start out as a smaller tower, and yes it does work).

So I had to raise the pivot point. Working with an in-place tower and pour new pillars to a new height, without binding the center pole. Grin I need to bring her down to replace the sole blade remaing on the mill with a proper set.


Full tower with a too low pivot point


The lower pivot point and rigging


Concrete form being built, that was interesting, lots of spray foam


Pillars poured with high strength concrete (glass fibers)


Form removed, Yeah!! the corners are true


From the front, I managed NOT to pinch the pipe wich would have made it impossible to ever bring down



Full Tower new base... next, cut hole in fence, redo some ofhte lattice, bring her down

[97fishmt]

Hi Rover

You put some steel in there didn't you? Concrete needs to be re-enforced for any kind of loading.
Re-enforced all the time actually.  Let us know how it works.

[Rover]

Rebar.. yep... everywhere.  I have an SDS hammer drill so I drilled 8" into the top of the old pillars and ran 4 rebar on each to the top of the new forms. Plus studding the lower pillars. There are 14 80lb bags total in the new pillars (fiber reinforced concrete, plus the rebar) .

So 7 bags each pillar at ~ 560lbs per pillar. The original pillar posts displaced some concretes a well, and they go down another 2 ft along with the pad, which is 3 1/2' at the center.

I'm still wetting her down as well.

I'm not worried about the pillars they will stand, and during normal use (not raising lowering) they share with the 4 corners of the derrick rig.
 

[ghurd]

Very Cool!
G-

[Rover]

Finally got aound to bringing the tower down, no issues

This phot is her down. In order to bring her down I had to nothch a hole in the fence, nd remove the tower front lattice. The 1700 lb Warn winch worked like a charm, and I think the garage door springs that ran from the base of the pilars out to the end of tower helped as well

All told 6hrs, prep, attach new hub and b;lades, back up.