Friday, March 29, 2013

From Jörg Sprave for Jörg Sprave

My name isn't very common in Germany. But I do have exactly one name cousin - a guy whom I never met. As far as I know, we are not even related. But he hasn't anything to do with slingshots, that much is clear.

I have a monster footprint on the web. The other Jörg does not. I have thought quite often about him, poor fellow must have gotten so many remarks and messages because of me.

He wrote me a message lately. A fan sent him a slingshot that was obviously meant for me! He asked for my address so he can forward the parcel. Nice!

I wrote him back, apologized for the hazzle, and expressed my general sympathy for the many other misunderstandings I might have caused. He said no problem! So I promised him a hand made slingshot. He was elated, and even asked me to sign it!

So I made a slingshot from Jörg Sprave for Jörg Sprave. Slightly spalted, well grained birch scales on a 19mm multiplex core. Linseed oil finish. Hand Mortar design (I know I gave this to Cold Steel, but for non commercial use I think that is still OK).





I will band this up with a nice target band set, ideally suited for beginners, and I will add some ammo, too. Who knows, maybe soon we will have TWO Jörg Spraves that shoot slingshots!

Sunday, March 24, 2013

Office wars reloaded

I explored the pump concept a bit more.

This time I made one out of cardboard, entirely with desk tools and materials. No Thera band, no scroll saw, no screws.

While cardboard, if used right, can be incredibly strong, it is a b..ch to work with. You really have to take care.

The shooter holds 12 two-eurocents-coins in the mag. You can also use US dimes and M5 washers, all having about the same dimensions.

It is impressive how much power this little thing has, propelled by just 10 normal, thin office rubber bands.

Sunday, March 17, 2013

Separating Oreos like a boss

Oreo, the maker of the famous three-layered cookies, launched a viral marketing campaign a few weeks ago. They hired four different inventors to come up with crazy machines. The most successfull video already has four million views:

http://www.youtube.com/watch?v=pii4G8FkCA4&list=HL1363533455

I was not invited to join, but I nevertheless decided to give it "a shot" (pun intended). Here is what I came up with:

Sunday, March 10, 2013

IWA 2013 news

The IWA, held annually in Nuremburg/Germany, is Europe's most important show for weapons and gear. A pure B2B event, so "normal" consumers can't get in.

I visited the show again, upon special invitation by Cold Steel. See this year's news - Zombie killing blades and axes, great arrow shooters, and even a side by side rifle that is chambered for four caliber (1" dia) ammo.


Deadly Marriage: Paper Planes and Kunais

Have experimented with the paper plane idea some more, and tried a Kunai modification that allows me to shoot them from the Machete shooting crossbow.

It works!

A specifically bent nail, attached with rubber, for bands with a loop attached to each end, and the paper plane as shaft/fletching. A length of paracord with a knot at the end, so it locks into the mechanism of the crossbow.





Shot from the Machete shooter, the thing flies straight, true, and with mighty force. This is from 12 meters distance.


Friday, March 8, 2013

Hand Mortar Lineup

The Jörg Sprave HandMortar (formerly known as ManuMortar) line is now ready to be presented to Cold Steel (tomorrow at the IWA show in Nuremberg).

Rubber, Osage Orange, Purpleheart and Red Cedar. Black, Red and Gold if you want (the colors of the German flag).



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The red cedar one is a bit different, I used very thin 9mm Multiplex in order to "simulate" a steel frame. Works really good.

Red cedar - 55 gramms, Purple Heart - 85 gramms, Rubber = 125 gramms!

Tuesday, March 5, 2013

Black Ops Slingshot

I want to give a total of four ManuMortars to Cold Steel on Saturday. I already have the Osage Orange one. Next, I tried something very different: Rubber as material for scales.

I bought a huge rubber mat, 1 cm thickness, on amazon. Not expensive. That isn't foam rubber, it is the massive type. Think car tyres. Butyl, of course, so useless for slingshot bands.

But it offers more friction than anything else. Like a competition grade motocross bike handle.

It was easy to shape (you can cut it, saw it out, file it, sand it - no problem). What you can't do is polishing it - it will always stay rough, like suede leather. And - like the motocross handle - it will always rub off a bit. So dirty hands are to be expected.

You can glue it onto wood with epoxy, no problem. The only issue arises when you finish the frame. No matter what you do, it is impossible to NOT darken the wood with the rubber particles that rubbed off. Since the effect is uneven (kind of blotchy), I decided to go ahead and use black ink on the wood. I put on the ink, then sanded with 1200 grit, then inked again - and afterwards, I applied linseed oil. The oil takes the ink deep into the wood, and seals it there.

The effect is stunning (I think). With Thera Band Black, this will look so cool. And the purchase you get from the rubber is out of this world.


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Saturday, March 2, 2013

2nd gen Manu Mortar

Kept working on the ManuMortar design for Cold Steel.

Following Tobias's suggestion, I lowered the clearance between the fork from 6,5cm to 5cm. This will allow the target shooters to keep the target "outside" of the frame, and it also makes the support grip style more comfy - especially for those with smaller hands.

Used Osage Orange for the scales this time. Bright wood, good contrast to the Multiplex. Just a bit of rounding, the heavy Moorhammer style sculpting isn't necessary on this frame. Will make production cheaper.

A great shooter! I am not sure if I will add the "dicks" for the tubular rubber. Looks more clean this way.


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