Bogged in winter blues, I struggled to get the rungs done.

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I chose round bar for the rungs because it is very simple, and makes a much nicer hand hold when hefting this thing around.  Eventually the hex head bolts will all be replaced with square nuts.   For the historical purist, screw threads are contraindicated.  However, for the experimentalist, flexibility in how this contraption is assembled makes sense from a development standpoint.  Rivets are more permanent than ideal if one anticipates changes…

A set of lower struts will connect to the ladder at the same point as the these rungs.  The struts will connect back to the stock, much like on Firefly, and stabilize the stock and framework with great rigidity.

The Occamists may object.  But then, they always do.

 

 

4 Responses to “Winter rivets?”


  1. Charles W. Fink says:

    Nick, in April I will be in Texas for about a month. When I’m there I am off grid except for a cell phone. I would like to contribute some boise d’arc wood to your project for you to test.There is a grove of trees that I have access to. If you can think about some dimensions and what kind of grain you want I can rough out a couple of pairs of limbs. I would need to know if you want heart wood centered or two limbs halved from the same log, stuff like that.You have time to think about it and you can get creative if you want. Lamination, etc. All of the finish shaping will be up to you, but I do have a band saw and I know how to use it. Free shipping and handling on this offer.


  2. nick says:

    Charles, that is a truly a kind offer. However, there are some design issues re: the limb irons that I have not yet resolved. In short,the cross section of Phoenix’s limbs is still up in the air. At one point, I was considering using a reflexed limb with the steel tension rod being straight across the concave back of the limb. That way the tension rod wouldn’t need to be set up on that bridge in the middle of the limb, like on Firefly. Let me think on it some and get back to you in a week or so. A pair of gently curved 3″ dia. logs might be just the ticket. I will check the density and strength of boise d’arc. Thanks again for the kind offer. Nick.


  3. Charles W. Fink says:

    Take your time, its almost two months away. I only mention it now in case the mild weather in Ct. changes my plans a little. It seems winter in New England has been cancelled.Hundreds of thousands of brand new snowblowers are sitting idle in garages across the east coast. I think you’ll like this wood, its very strong but its not brittle. With such a rigid frame and the torsion wedging improvements, every possible weak link down the line will want to show up.


  4. Nick says:

    I am thinking that a couple of pieces 24″ long and 3″ diameter at the thick end, would be good for ballista limbs. Perhaps let me know when you get ready to go down there. Thanks again, Nick.

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