Haven't built a bow in 2 years now

[Badger]

I am only going to leave that pic up a couple of days then remove it, i don't think I am supposed to post it LOL. Steve

[Dane]

Jude, regarding size of artillery, I think that was not the same issue for a Roman army as it is for us. Some of the machines were absolutely enormous monsters, based on the sizes of stones found at various archeological sites. They were far too complex to have been built on site, as some would suggest, but were probably transported from centralized shops, or borrowed from allied city states and forces at times, too. Transportation and logistics are a big factor in who wins and who looses a battle or a war, then and now. I’ve designed my little 2” (spring diameter) arrow shooter so it fits into the hatchback of my Saab 9-3. Easy to move, easy to play with, and it does reflect the small size of the arrow shooters that would have accompanied a late Republic / Early Empire legion.

One guy in our legio built a very small stone throwing ballista. Small is relative in artillery. It weighed over 3,000 pounds and took a huge trailer to transport, was dangerous to set up and break down (each of the two spring assemblies weighed close to 300 lbs and took 2 guys to manhandle), and had teething problems never resolved because it was impractical to transport and use. We only fielded it 2 or 3 times over a 2 year period. It is sadly now the property of a Hollywood prop house.

Steve, that machine looks familiar I recall telling my wife while watching the episode “Oh, that’s Steven Gardner.” Then I had to explain who you are. I think she thinks all of us have too much time on our hands, and are prone to violence, but as I point out, it’s better than my hanging out in bars all day and tipping strippers. What is debatable is which activity is more fun.

Dane

[Badger]

   Dane, I actually had built several versions of that same machine in smaller scales trying to fine tune it. The best results I had were converting it to a trebuchet. So much of the energy went into rotating the drum and lifting the throwing arm that the efficiency was horrible. As a trebuchet I was able to tune in a stall speed allowing the payload to stop the arm sapping all the energy back out of it. More than doubled the distance I was getting. Steve

[Dane]

Steve, sounds a lot like the same challenges facing an onagar builder. Those too use a sling to hurdle the stone. Most people who build follow Payne Galloway or Marsden, or some of the other earlier builders like Schramm. In the smaller machines, stopping the forward momentum of the arm is one of the big challenges, and where failure most often occurs. I have a friend really into these machines, if you want me to put him in touch him.

So you had build that same Da Vinci design before? Do you have any photos of your work? It is a striking looking machine, no pun intended.

Dane

[Badger]

Dane, I hadn't really looked at the catapults too much until the show came along. I folled around with the prototypes durring and after the show was completed. I doubt if I will do much more with seige engines besides this last project I have set for myself. If I don't get the results I am hoping for with a 20 footer i will likley just abondon the project. I belong to a sight called catapult message board. These guys are brilliant some of the stuff they are comming up with. I iamgine your friend proably frequents this sight as well. Steve

[El Destructo]

Badger...now that is quite the Contraption there...I would really like to see that work.....in Person!!

[Dane]

Dane, I hadn't really looked at the catapults too much until the show came along. I folled around with the prototypes durring and after the show was completed. I doubt if I will do much more with seige engines besides this last project I have set for myself. If I don't get the results I am hoping for with a 20 footer i will likley just abondon the project. I belong to a sight called catapult message board. These guys are brilliant some of the stuff they are comming up with. I iamgine your friend proably frequents this sight as well. Steve

Steve, could you send me the url for that message board. I may already know it, though not sure.

As for me, the catapults are more facinating than bows, so much is unknown about them, and a great deal of work is to be done in the field. My plans down the road are to build a gastrophetes (belly bow), probably the first catapult, a little hand held machine featuring a composiite bow. The closest that has been attempted was one by Schramm in the early part of the last century, but he used a metal bow. The arcuballita is interesting, as is one scholar's theories about tiny hand held dart shooters. The Hatra machine is something no one has tried to recreate, an inswinger with an all wooden spring frame.

Ultimately, I want to build a machine using only the tools and methodologies available to the Greeks and Romans. That means to me all hand built using forged metal tools, ancient metal working, alloys, and casting methods, and even the raw materials gathered and processed as we think they would have been 2000 years ago. I've been compiling the tools (chisels, draw knives, etc. Not cheap, but the work of one smith I buy from is exceptional), and am starting to use them in regular projects. This machine will have sinew ropes, etc.

Dane

Dane

[Jude]

Jude, theoreticaly with bows each time you double the size you 8 times the payload and 8 times the stored energy and double the dstance, don't quote me on that but i think I saw that when researching somewhere. I plan to start with a 12 ft bow then a 24 ft bow and these should tell me a lot about how it will scale up. Going to use a simple pyramid design to avoid tillering, will also allow some slack in the design instead of trying to peak it out right away. More intertested in the scaling process than peak performance at this point

Steve, well, it looks like I wasn't too far off with my 6' 50# bow becoming a 12' 400# bow.  Good to see I'm not losing my mind just yet.  The point I was getting at in my long-winded, meandering sort of way, was that the wood itself would be under twice the strain in tension and compression in the 12' bow.  I think the bow would have to become progressively more of a flatbow as it grows, increasing more in width than in thickness, for a big bow to work.  However it turns out, it's likely to be a fun project.  I just wouldn't want to be in the way if it blows.  I don't think artillery failures are a pleasant thing, regardless of the propellant used.  Good luck.

Dane, I was just going off on a tangent there, sorry.  It just occured to me that since the propelling force of modern artillery is based on volume, not on surface area and distance between working surfaces, we can scale up artillery as much as we want.  As for portability, the biggest thing we use in the Army today, is essentially a 6" gun.  The 8" to 16" guns of ww2 are gone.  The German railcar guns required an entire battalion, of around 800 men to service one piece.  They only had 2, because they weren't practical, and used them as an intimidation tool, rather than a tactical tool.

[Dane]

Jude, the older artillary pieces are interesting. I was never a redleg, I was an 11Bravo. When I was in Germany, I was with a Pershing warhead detachment, another form of artillary which would have made a very large boom had we used them. None of us would be here on this board though if they had ordered a fire mission. One writer called the Cold War era infantry the doomsday grunts, which I think is appropriate, and wish I had coined the term.

Dane