Over the summer, one of my friends received her scuba diving certification, so as a birthday present, I built her a suction cup spear gun toy. It was a really fun build, since I got to play around with it a bit before I gave it to her, and it cost me $0. With the right rubber bands, this toy has a range of over 20 feet!

Just don't shoot anyone in the face. It's not nice.

Materials:

Suction cup dart heads
1/8" dowels
clothes pins (x3)
3/4" thick hardwood, (I think I used maple)
misc. rubber bands
wood glue

Tools:

jigsaw
drill press/gun
power sander
miter box/saw
dremel (optional)

Step 1: Find a Template

I did a bunch of Google searches for "spear gun" to get a feel for the shape I'd be making, and eventually found this template of the handle. I then sized it in Word (as shown in the .doc file), printed it out, and taped it to the wooden panel.

I approximated the total length to be about 14", in order to keep it toy-sized.

template.doc
Download

Step 2: Make the "spears"

I cut the dowels to be about 11" each with my miter saw. I tore off the suction cups off some old darts from a spring loaded plastic gun - the holes were a tiny bit small for the dowels, but ended up fitting quite snuggly.

I secured them together with a dab of Elmer's glue to the ends of the dowels. Afterwards, I set them aside to dry.

Step 3: Mark and Drill the Trigger Hole

I traced the template in pencil, and approximated where the trigger hole would go. This is mainly for aesthetic, and also for the index finger to go into, to give it a more realistic feel.

I first drilled a pilot hole with a 3/32" drill bit, and the trigger hole was drilled with a 1" drill bit.

Step 4: Cut It Out

I (very slowly) cut it out with my jigsaw. That was pretty straight forward.

I tried to approximate the curves of the handle, but any mistakes would be removed later in the sanding.

Step 5: Sand That Sucker Down

I used 120 grit throughout, both with my sander and by hand on the edges.

To make things go by faster, I used my dremel tool with a sanding disk attachment to smooth out the handle grooves.

Finally, I used 320 grit all over by hand. With maple, this makes the wood extremely smooth and even delightful to touch.

Step 6: Filing the Spear Groove

In order to shoot the darts straight and not have them slip off the top, I needed to add a groove on which the dowels could rest. I marked the groove down the middle of the top, ending it where I approximated the clothes pin trigger to go.

Step 7: The Trigger

For the trigger to work properly, it has to align the spear and the rubber band, thus the trigger has to somehow hold the end of the spear, or else the spear rests on the guns top surface, under the rubber band's path.

Thus, I drilled 3/16" hole at the mouth of the clothes pin, as shown, to hold the end of the dowel so that the rubber band catches it

Step 8: Glue the Clothes Pins to the Body

The two forward clothes pins will act as both rubber band anchors and ammunition holders.

I glued them to the body as shown with wood glue, clamped, and let dry.

I did the same with the trigger, approximating the distance between its end and the butt of the gun, taking into account the ergonomics of a smaller person's thumb's reach to pull down the trigger.

Step 9: Lock and Load!

I used three rubber bands tied together, but it all completely depends on how strong the clothespin spring is.

I also added a short length of duct tape to the rubber bands where the trigger holds them in place, to reduce the wear.

I hooked the fronts of the rubber bands into the clothes pins as shown, and they hold pretty well. I can guess that these rubber bands would have to be replaced every few weeks with constant wear and tear, but otherwise it works perfectly fine.