[TowerTalk] Big rotators

[Kurt Andress]

Original Message
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Message: 7
Date: Thu, 27 Apr 2006 21:44:57 -0700
From: Dino Darling <dino at k6rix.com>
Subject: Re: [TowerTalk] Big rotators
To: towertalk at contesting.com
Message-ID: <7.0.1.0.2.20060427213803.0346be60 at k6rix.com>
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I just sold a Prop-Pitch motor to Kurt Andress, K7NV, while at 
Visalia.  Kurt rebuilds these motors, converts them to rotors and 
uses a modified M2 control box.  I've seen his work and he comes 
HIGHLY recommended!

http://www.k7nv.com/notebook/ppinfo/
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Dino, Great to see you in Visalia!

For those interested in such things....
I will be at Dayton this year and will be showing one of my small prop pitch systems along with the brand new control box I developed with Green Heron to properly & reliably run these things. 
Stop by booth 531 and at least say HI, 
Looking forward to seeing everyone this year.!

73, Kurt, K7NV
www.k7nv.com


On another note: 
Regarding the slippage problems with the OR2800 mast clamps. The cast teeth on the clamp jaws are very irregular and won't fit any size cylinder properly. 
I've put these jaws on several prop pitch systems. I resurface the jaw teeth to fit the mast that will be in the clamp. 
This can be done with a tube or bar that is the same size as the mast and some wet-or-dry sandpaper.
This greatly improves the gripping capability of the jaws. I also recommend that the user pins the mast to this clamp with a grade 8 bolt that is provided. This works very well because the prop pitch can't be broken, like other rotators. If the prop pitch is overloaded it will just be driven backwards and can easily be recalibrated at the control box.
The only guy that I've heard from that actually was able to drive the pp backwards was turning a 30' dia EME dish.