Bowling Ball Slingshot based on Leonardo Da Vinci' Design?

Seems like the slingshot cannon video will soon be viral. It saw 45,000 views in the first 36 hours already, with a steep increase! People love it, almost 1300 likes and just 6 dislikes...

I was just covered in "Stern View Magazin", a German magazine focussed very much on photos (only a few lines of text). Two pages! They said that the only challenge I did not master was to make a bowling ball slingshot...

The Discovery History Channel did a project a few years back, about building two of Leonardo's designs - the glider and also the giant crossbow. The glider worked, but the crossbow did not. The wooden limbs broke, weren't elastic enough.

Using a ton of rubber instead of the wood would no doubts work much better.

What do you think?

This week's winner is...

..."mckeee"!


Congratulations. Please PM me your address and your choice in slingshots (Panther or Cougar).

Finally. At last. See the cannon in action.

This was probably the most exhausting, but also the most satisfying and fun vacation week I ever had.

It took four days to build the cannon, and then one more day of basic filming with the great guys from The Tapefilm Crew before we brought the cannon to its playground - Tobias's wonderful farm.

He drove the weapon to his romantic apple orchards, on the hottest day Germany saw in the whole year... and then we fired it. Fired it. Fired it some more. Did I mention that we fired it a lot? :)

The performance of this thing is amazing. We did not exceed the strength of 36 conventional "hunterband" catapults (18 times the draw weight and twice the draw length), as it was getting tough to cock the mechanism even though we used long crank handles.

See for yourself:

Watch the video on youtube!

We had a blast that day, even added a full blown slingshot tournament with several different challenges in the evening. I drank less beer than Tobias and even half cheated in one discipline (couldn't resist), but he nevertheless beat me 94:91  - the guy is just a great shooter, hats off.

Now I will go back to my job, a big show next week. But I am much relaxed, having achieved something I started to work on like 9 months ago.

Plunger-Slingshot: Watch it on German TV

Here:


 Galileo Extreme: Plungers

EDIT:
For those who do not live in Germany, the video won't play. But do not despair, "Milchi" has downloaded the essential parts and uploaded them on youtube, here:  Thanks, Milchi!

(Sorry for the German audio)

Ready for some action!

I have newfound respect for cart makers.

I had underestimated how much work it is to make a simple, minimalistic carriage. Fitting the axis into the antique wheels was hard to begin with. Making the hub was not easy, too - especially adjusting the distances.

Then, I found that the forces on the wheels when you try to turn the cannon to the left or right are tremendous. After all, the axis is fixed and the wheels do not turn individually. I had to make a solid fitting from flat steel just to solve that issue.

The whole thing shoots very well, and reloading is fast and easy. But it does look a bit spindly, really. But I assure you it is quite heavy, probably over 100 kg.

Film team tomorrow, and then off to Tobias's farm on Friday. Will see if we can make the cannon a bit better looking. The spindly look is unacceptable.

It is alive!

Yes, despite the sweltering heat, I did my dues and have done the first test shots today. The winch assembly is finished, and very solid (have to cut off the excess steel tube and bolts). I tested the mechanism by pulling back (against the lock) on the crank handle with all my strength, it holds.



No carriage still, so I can not cock it more than 85% (the sled hits the stands at that point). And I "only" used two layers of full with TB Gold per side, one fifth of what I am hoping to do in the end. 

It shoots!  And it exceeds my wildest dreams.

Sorry, no impact pics yet because I don't want to spoil the tension, but this thing is ab-so-lute-ly awesome. I rarely say that about my own stuff, but in this case there is just no way I can downplay the awesomeness.

Tomorrow, the carriage assembly and some minor optmizations. Stay tuned. 

Day 2: The Cannon "Barrel" Assembly is done

A hot day, sweaty work... but I got it done. The frame is finished. I even found enough time to start on the crank handle. The "cross" is made from 12 mm solid steel, 33cm at each side, strengthened by a 16 mm steel tube in the critical first 15 cm. This is all welded together, very strong.

Transmission of the crank is 26:1, means, if I go up to 500 kg (1100 lbs) of a draw, I have to pull with 19 kg (42 lbs) force at the end of the handles, very doable. 

I decided to go with the clamp-on attachment method, will increase safety be using a round rod as an additional "wedge". This is the strongest known attachment method.

Tomorrow, the winch has to be finished, and the two drawing ropes have to be installed. With some luck, the weapon will be able to fire tomorrow evening. Wednesday is reserved for the carriage assembly.

Cannon: Trigger/Lock/Sled Assembly finished, plus This week's winner!

Finished the trigger/lock/sled part today!

As you can see, the sled will glide between the two parallel 4x4 (10cm square) wooden beams, which are 33 cm apart. The trigger is a long upwards pole that you have to pull back to fire. I drilled a hole near the top of the trigger pole so I can later put a length of rope through it and pull from, like, 20 meters back (safety distance).

The winch will roll up strong mountaineer grade rope, actually two of them (you can see the massive rings I attached for the two ropes). It will take about 30 turns of the winch wheel to fully cock this monster.


The third picture shows the 4kg shot put ball, loaded in the double pouch. This is the largest diameter ball (10 cm) the weapon can fire, smaller balls are never a problem as long as you don't go smaller than 25mm (1").

The conventional slingshot is to give you a feeling for the size of the cannon...

Tomorrow, the "barrel" assembly!

Oh, by the way, this Sunday's winner is PetersonOD... congrats! Send me a PM on youtube with your slingshot choice (Panther or Cougar) and your address.

Next raffle is on, of course! Winner will be drawn next Sunday.

Cannon: Rubber arrived

First serious cannon building day today. I basically have five days to make most of the parts, the film team will show up on Thursday and film the preparations. Then we will all drive to Tobias's farm and put it together, then shoot it...

Bought 45 meters (50 yards) of Thera Band Gold. Will start with six full layers of TB gold per side (about 220 kg = 484 lbs of a draw weight), then go up if things hold. I think for the 720 grams boule balls, 220 kg will be fine, but for the 4 kg shot put, we are talking more like 500 kg...1,100 lbs.

Will fire up this ole truck of mine and fetch the 4x4 beams I will use as "rails" for the frame.

Watching your own funeral...

Remember Mark Twain's "Tom Sawyer"? There was this great scene where Tom and Huck returned from the cave, just in time for their own funeral.


As you may recall, I left the slingshot forums a while ago, which did cause some stirring. I took a peek - feels strange, really like witnessing your own funeral. Somehow people think because you have stopped posting, you have disappeared as a person. Guys that used to be honey sweet now dare say kind of nasty things... especially in the so called "rebel" forum.

A nice justification for the step I took, really! But guess what... I am not dead, and I still love slingshots!

Whereas my channel and especially this blog continue to work really well for me, I now realize how much time I spent on the forum for very little attention. I mean, I posted a thread on the forum and got between 100 and 400 views, in the end, after a few weeks maybe. I post a new video on youtube and get between 1500 and 6000 views on the first day.. the largest forum has 3,000 members, my youtube channel has 22,000 subscribers.  Fact is the forums needed me more than I needed the forums.

But just to clarify things, I am neither against hunting nor against target shooting. I was insulted by a German forum member who thinks he is the master and self declared speaker of the "elite" slingshot shooters, some kind of superhuman, noble athlete whose immaculate, sublime sport is now tainted by my lowly presence and activities. Noone else ever insulted me (that is, before I left).

I do like target shooting, I even crossed the pond to go to the ECST in 2010 an 2011... I just don't think target shooters are any more "elite" than those who hunt, shoot at cans or... ballistic gelatin, if that is what people want to do.

I did not leave the forums because of the rather naive fellow who insulted me - I left because I was not getting the support I was expecting from the site administration. I simply felt let down. Given how much time I invested and how many members I brought in, I was disappointed.

Now I have far more time to follow my own projects, which mostly means making slingshots of any kind.

And videos, of course!

PS: I hope that my own website and forum will be online soon.

Tanto/Pachinko!

Made this slingshot today. I named it "Tanto/Pachinko", as "pachinko" means "slingshot" and "tanto" means "dagger".

The handle is the original tanto one, I just welded a slingshot frame that fits the same as the blade. These two are now fully interchangeable.

Feels great in the hand!

I did not polish the steel, just brushed it to give it a rough "fighting" look. A most unusual slingshot.

New "Six Circles" shooter, made from Maka Mong burlwood

I had this piece of rare Maka Mong burlwood I ordered some time ago.

The back side was kind of incomplete, one side was much tapered. I figured that I could make another full "six circles" shooter from it, and got to work. The wood is very hard and has a very distinctive smell.

A multiplex core, for stability. Came out beautiful! The burl is incredible.

Home made crossbow: Finished!

Finished the weapon today, works very well!

Project: Making a crossbow from an old compound bow

I still have my Razor Edge compound bow. Not a bad weapon, but ever since my Liberty 1 arrived, it really only caught dust.

So I had this idea to use it as a part for a home made slingshot crossbow, much like the medieval style rubber powered model I am so happy with.

Took a whole afternoon, but it is now very functional. Medieval style trigger and rolling nut meets modern compound technology! The low letoff (15%) allow very easy trigger pull weights, making the weapon very accurate.

It shoots very well, but it is very ungainly to look at... still. Will make it nicer tomorrow! A video is called for, too.

Winner number 3 (of 52) is...

..."Ryan"!


Congratulations. Please PM me your address and your choice in slingshots (Panther or Cougar).

For the others, 49 more chances! New video will come up probably today, maybe tomorrow (lots of work to do and tomorrow is a holiday, no work). .

Making The Cannon Pouch

In preparation for the big event in two weeks, I started to put things together.

Today, I made the pouch for the monster. I want to use boule balls, 2kg, 3kg and 4 kg shot put as ammo. The pouch has to be big enough for the largest ammo type, which has 10 cm (about four inches) in diameter, solid steel. (The pictures show a 15 mm steel ball, typical larger size slingshotz ammo, in comparison.)

As the clamping mechanism needs some space, this means the pouch has to be about 50 cm long and 10 cm high.

I punched in 4 cm holes for the centering and also for the bands.

As I want to go up high in draw weight, I used very thick leather (3 mm), well made and totally strong (I had to hammer about 50 times PER HOLE on the hole puncher, which is really sharp...). I used two layers for a total thickness of 6 mm.

This meant the inner layer had to be cut shorter to end up even when the pouch is wrapped around the ammo.

The pouch alone weighs 200 grams, more than a 30 mm steel ball (130 grams)!

I will used looped Thera Band Gold, so I can simply add one more full width band when the shooting starts.

This pouch will endure crazy draw weights, and it will need every bit of that endurance.

Natural and Antler

Another natural from the dogwood tree (cornus sanguinea)...

I love that wood, it looks like ivory when polished. And it is very strong. I added antler scales, just to try something new, and also to straighten the handle (it was off to one side). A low, narrow fork allows really strong bands and offers lots of power.

A frame for the experienced shooter, you have to flip this to avoid fork hits. But for those who can handle it, low and narrow forked hammer grip slingshots deliver the hardest shots.

The Slingshot Cannon Project - Wheels arrived

The last week of August will be dedicated to the making and shooting of the slingshot cannon.

The parts are starting to come in. Ammo is on its way, 18 Boule balls (1,6lb each), two each of 2kg (4,4 lb), 3 kg (6,6lb and 4kg (8,8 lb) shot put balls.

Bought the cannon wheels on ebay, from an old firefighter carriot (three ft. dia, iron ringed). 1 Euro for both! My wonderful wife drove 50 miles to fetch them (always good to have a pickup), but this will look gorgeous and saves a lot of time.

This project is so exciting... can't wait to shoot the shot put against the (clonker) car I bought just for the purpose.

Plunger video: Will be on prime time German TV soon

As you may recall, a German film team visited me a while ago. They filmed me shooting a plunger ("Pümpel") with a slingshot crossbow, for a "science entertainment" show called "Galileo" on the German Pro7 network.


Watch the trailer on youtube

The piece will be a part of a Galileo "plunger" special.

It will air August 25, 7:05 PM. My "turn" will be around 8 PM, truly prime time. The network will make it available worldwide on the web, I will post the link after the show has aired.

First "natural" from the dogwood tree

Here is the first "natural" from the tree/brush (common dogwood) I had to fell.

Started with an ugly fork and sawed the "handle" of, then I carved a nicer handle from a thicker branch and attacged it in the magic "Phoenix" angle (120 degrees). It has a steel core for total stability.

The wood can be polished like ivory, feels fantastic. It is so dense and hard.

I added a "collar" from shrink tube to cover the "throat cut". Nice cushion for the webbing of the hand, too.