Who makes Artillery ??

[AuxArcher]

Sandrus, thanks. I'm not sure who or what I am going to shoot. Any suggestions?

Dane

[AuxArcher]

Hi, Duncan. I hope you got my PM? It was a question about the length of the bow arms, specifically where you would measure the length. From the tip to where it enters the rope spring? Or would that part of the arm be part of the total lenght?

The rule is 7x rope spring diameter, yes? I'm leaning toward from where the arm emerges to the tip. The arm will of course be longer then, to account for where it is inserted into and is held by the spring.

Thanks if you can help.

Dan e

[P. Clodius Secundus]

Dane,
The Manuballista is looking great, I hope you can bring it to Founder's Day at Higgins. When you get ready to make up the metal cladding I'm sure my local metal fab shop can cut and bend the pieces.
Duncan,
Did you get a chance to see the design for the Carroballista that I posted on the Carrus and Carroballista thread? I've been doing some photoanalysis of the images on Trajan's and overlaying CAD drawings of just the weapons parts. My hope was that by holding the aspect ratio (height/width) the same I can make all the CAD versions the same size and get some rough consensus as to the relative sizes and placements of components. I can also compare them to my design as sort of a reality check. I superimposed a model of a 79mm washer field frame and it sure seems like it will all work.
Has anyone out there tried using parachute cord AKA 550 Cord for spring rope? It's thin nylon cord with an outer sleeve of colored sheathing. It's rated at 550lb test (hence the name) It might be braided somehow to make up a larger/stronger cord. The nice thing is that it's available in a brownish color and possibly in tan as well. I bought a couple of lengths to test with.

[Magnus]

On that note...what about some rock-climbing rope, or gear rope?

[D B Campbell]

Hi, Duncan. I hope you got my PM? It was a question about the length of the bow arms, specifically where you would measure the length. From the tip to where it enters the rope spring? Or would that part of the arm be part of the total lenght?

Hope you got my PM, Dan.
In case anyone else is interested, I'd say that the 7d length of the bow-arm is simply the distance from heel to tip. And once the heel has been jammed through the torsion-spring, there's about 5d (5-and-a-bit d) left sticking out.

(If anyone has access to a definitive Len Morgan original, they could maybe confirm this? )

[JVL]

Here is a report on my recent progress on my vitruvian scorpio.



The plating is a bit too thick, but the wood is not correct so it strengthens it a bit.

[Titvs Statilivs Castvs]

Can't see any image. :?

[Virilis]

Way to go, Juuso :wink: !!

[JVL]

For those who can't see the picture:

http://www.pienoismallit.net/galleria/malli_1901/

There are other photos as well.

[Titvs Statilivs Castvs]

Very nice. When do you hope to finish it?

[JVL]

Within a month or so, when I get the modioli.

[jkaler48]

Daniyal Steel Crafts is working on a source in India for Sinew Rope for
Roman Artillery.
Here is thier Email address:
[email protected]

John Kaler
MSG, USA
Retired
Member LegoV (Tennessee)

[Crispvs]

"If anyone has access to a definitive Len Morgan original, they could maybe confirm this? )"

I won't be seeing our trispithimus again until February but I could check it for you then. Otherwise you could do worse than giving Len a call.

Crispvs

[P. Clodius Secundus]

Seasons greetings to my fellow ballistophiles. Here's a copy of my Visio drawing analysis of the seven iron-framed ballistae depicted on Trajan's column. Using a picture of the original carving as a backdrop I overlayed a simplified line drawing so that I could compare the relative dimensions and features without the background "noise" of mules, troops, etc. The comparison has led me to a few conclusions that will be reflected in my final design.
1. All of the visible bases (5 of 7) were monopods.
2. All three of the fully visible bases have a cross-foot with two angle braces and their overall height is 2/3 or less the distance between the field frames.
3. 6 out of 7 have sliders that project well beyond the field frames even when the weapon is loaded.
4. The top covers on the field frames are all conical (to shed moisture/rain, I suspect) the bottom covers are conical on only one.
5. On all seven the arched portion of the kambestrion (top strut) is 50% or greater of the width of the total distance between the field frames.
6. Four of the seven appear to have a kambestrion that is either "I" shaped in cross-section or actually made up of two separate bars.
Taking the last observations into account I have redrawn my carroballista with a two piece wider-arched top brace. There are a number of possible reasons for having a two piece strut. First, it would be easier to proplerly heat and forge two thin bars than one thick one. Second, if a single bar were to fracture it would be a catastrophic failure. With separate bars the failure of one would likely lead to a slower collapse. Third, two thin bars with a space between would be easier to see through than one big thick bar. (That last reason is for those who still think that the frame was widened to increase the field of view :wink: ) Overall this has led me to believe that the larger set of pittaria brackets may actually have been at the top of the frames to accomodate both bars and a wooden wedge between them. As with all my designs this will be subject to change upon further reflection, but this is where the Trajan's images are leading me.
Happy New Year to all.

[richsc]

Jumping in late, but what wood are you using? Pine? Oak? Ash?