FountainPenFan

While perhaps not the best overall homemade, blowguns are quite fun to use and likely the easiest to make. I recall getting the 100ft ranges you mention with a four foot long piece of 1/2" Sch40 PVC, practice, and stock tagger darts (which can be had at Toys-r-us, since Target doesn't carry them anymore.) You can get decent RoF by having a handful of darts in one hand ready to load and simply feeding them after each shot. Blowguns are also extremely quiet compared to most blasters I've heard, making it harder for an opponent to dodge (you can even slide a 4 inch or so long piece of pool noodle over the muzzle of a blowgun for even quieter shots.) You can shotgun 2-3 darts at 50ft ranges (taggers, PVC) without much difficulty. Probable cons are moving the relatively long barrel around indoors (though a recent test with an 18" PVC barrel and stock buzz-bee suction darts got roughly 50ft ranges, so shorter barrels are an option) and the requirement of not being terribly out of breath to fire. I plan on making a bolt action, magazine fed wood frame/PVC barrel blowgun after finals this week.

Looks like cool stuff. I also wouldn't worry about too much strength (as long as it's cold...) as you can just mash more of the stuff on your part in most contexts. Repair is probably as simple as "push the other way". At some point material cost will be an issue, which seems roughly 1.5x as much as ABS filament by mass. This is much faster, will make smoother shapes, and doesn't require a robot with a hot-glue gun.

True, though it would probably be best to make frames and other large sections of homemades out of cheaper materials (i.e. the hardwood I will be using for frames.) I don't know about filament, but this plastic does have the advantage of reuse for continued development of parts or designs - that aspect might make it more cost-competitive with the filament. As you pointed out, this obviously doesn't require any use or access to either drafting software or printer hardware.

I'll order some of the plastic and begin work on my project, and post results here. I will probably make the bolt handle/knob for the action out of the InstaMorph, with a wooden dowel bolt, hardwood frame with InstaMorph grips (since you could make a very nice custom molded grip to fit your hand around a wood core), and PVC barrel with InstaMorph braces to bind the round pipe to the flat wood.

I don't have pictures, but I was able to make a trial construction of the 3rd draft. I left too much room for error in making a dart guide out of four cut pieces of wood attached together, so the sled wobbles up and down quite a bit when not under tension. I have not tested it with tension yet, and likely won't because I don't expect it to work well.

So, I'm taking some of the advice from this thread and also changing the design from a faux crossbow to a more realistic shoulder mounted ballista (so I'm dubbing it the SMB.)





Just like a ballista my design uses rigid arms (blue) that pivot under tension to move a bowstring. The rail is now to be made up of 4 wooden dowels (pink) precisely spaced apart that will directly guide the dart as it is pushed from behind by the (dark red) block. The catch block (red) is also separate from the trigger in this new design, and for the trigger I plan to release the bowstring from the catch block by using a set of 2 connected clothespins: one inside the dart guide right by the catch with a string running through a hole in the bottom of a frame and attached to a second clothespin. When the outer clothespin is pressed, the inner one should have the same amount of travel and lift the string onto the angled part of the catch.

I will attempt the new design this weekend.

Less 3D models and more actual builds please. I'm going to close this thread in 1 week if there isn't any evidence of something actually being built.

Alright. I am going to be meeting with the friend who is going to be helping me with getting (more inexpensive) wood and making all the machined cuts this Friday, and was just posting the design's development to see if there was any input. Thank you for the notice.

@Meaker VI: Interesting design. My only question is if those round pairs of pegs at the front are the mounts for whatever you're using for the tension, and if so I wonder if you'll have unnecessary slack as the dart pusher nears the front of the rail. I'm keeping with the crossbow's perpendicular arms so that I can have tension throughout the travel of the dart pusher.

After going back to the drawing board:

















New trigger/rail sled cutaway:

The tube, taking the place the block with the dart peg, which will avoid the need to coat the inside with acrylic and will be made of either a metal tube or PVC pipe.

EDIT

This version will have tension the bottom and top, and there will be rubber bands stretched across the two paler blue pins near the trigger block to act as a trigger return.