One of the most important parts of a good atlatl is its spur; the “hook” on the end; the thing that fits into the cup at the rear of the atlatl dart. Think, “ball and socket.” During the throwing motion, the tip of the spur starts out in the cup of the dart and as the atlatl is levered, the dart rises and the cup of the dart rotates (or should) out of and on to the top of the spur.
When the atlatl is vertical in the air, the dart is sliding along the top back of the spur, connected to the spur only because the atlatl is at this point moving faster than the dart.
Anything that prevents the spur from smoothly rotating into and out of the cup of the spur and anything that prevents the dart from smoothly disengaging from the spur is a sure fire way to create a misfire.
The spur designs most likely to cause problems are:
1. A long, narrow, sharp, pointy spur tip. Such a tip is likely to dig into the cup of the dart and tear the rear end of the dart open. The tip of the spur needs to be rounded and blunt, again, think ball and socket.
2. A spur angled 45 degrees into the atlatl shaft with more atlatl shaft behind the spur. The extra wood behind the spur is likely to smack down on the dart just when the dart is about to disengage from the atlatl. This act is usually accompanied by a loud “thwack!” noise.
I have seen many of this kind of atlatl spur designs and the reason is usually “ease of construction”, as it is always easier to drill a hole at an angle into the atlatl shaft and insert and glue in a peg to act as the spur than to fashion or carve a spur correctly into the end of the ataltl shaft.
3. A spur attached to the atlatl shaft using thick bindings. Again, during the throwing motion, the spur rotates into and out of the cup of the dart. The rear of the dart then slides onto the top and back side of the spur. If binding is present on the back side of the spur, then the rear of the dart will slide into the binding.
4. A completely rounded spur. The possibility exists that the dart butt will slide off one side or the other of such a spur during the throwing motion. The possibility increases if bone or antler or some other dense material is used as the spur.
A good design for a spur:
1. The tip of the spur should be rounded and blunt so that the spur can easily rotate into and out of the cup of the dart. Think “ball and socket”. This requires that the size of the spur tip must compliment the size of the cup in the rear of the dart.
2. There should be no atlatl shaft wood beyond the end of the spur.
4. In my atlatl spurs, I carve a slot down the top back of the spur so that the butt of the dart will not slide off one side or the other of the spur during the throwing motion. Flattening the top back side of the spur serves the same purpose.
5. The best atlatl spurs I have seen are rather small, and angled at 30 degrees or less relative to the atlatl shaft.