11 replies to this topic

[Buffdaddy]

As is obvious, I'm going to be making some Tornadobows, but with SNAP-style internals. This has several advantages, mainly that since the plunger head and catch are one and the same, I can theoretically keep the stock trigger. This would greatly simplify things and, pending blaster construction, allow this kind of blaster to be (slightly) more common. However, I have several things I"m looking for as references before settling on the final design, and I'm searching to no avail:

1) Examples of homemades that use 1.5" PVC as the plunger tube
2) What the best method of constructing a plunger rod ramp is these days (normally for clothespin triggers
3) Anything else you can think of

That, along with any other pointers you can think of, would be greatly appreciated. Currently, the plan is to use an enlarged version of Nerfomania's Pumpsnap, but things can always change.

[Exo]

There'sTHIS, but it has a really crappy plungerhead (no offense, Mr.pzowned).

There's also Venom's AT?K pump head that might be able to do something here, I used a version of it on a LAMP.

I think most people use a PVC endcap that's been psychotically sanded, but you could get fancy and make something on a lathe, or a suicide catch might work (langley's design).

You could also try the semi-overused ring catch design.

[Edible Autopsy]

Pertaining to the ramp, a superlative plunger head is definately the most reliable/stable/long lasting.

[Carbon]

I think most people use a PVC endcap that's been psychotically sanded

A better solution is to use a rounded end endcap. Those work pretty much off the shelf, with minimal sanding...they're all I use. Sanding a square end endcap works, but it greatly weakens the endcap: go too far, and it can (and will) break.

[Curly]

I trust those are 100% homemade, not homemade internals. If so, I have been tinkering with a 1.5" PVC pump action SNAP. One thing I very strongly recommend is using TantumBull's plungerrod-free design. They allow a wider variety of springs to be used, and no small slots to cut. I don't know whether the TornadoBow itself had a telescoping priming handle, but plungerrod-free SNAPS make it easier to incorporate one, for facerape and such. If you give me the draw and some other specs I can make a CAD drawing if you like.

The floating plungerhead I am using is superlative. Nothing I am using is from Mcmaster, so that's handy. The large washers are 1.5" OD and about 1/4"ID. For my O-ring rest I used a 1/2" ID washer, a very thick one at that(if the O-ring is pinched it will pop off). It's just under 1.5"OD. I used some small 1/4"ID washers to space out the catch area and to give the nuts a better spot to sit. Behind that I used a 3/4" PVC to 1/2"PVC adapter for E-conduit. It's like a flat endcap with a hole in it. You can secure it by placing a small washer in the 1/2" coupler before assembling. To attach metal wire I drilled a hole on each side of the coupler, and looped the wire through. To join the wire buy a metal sleeve and hammer it furiously.

To summarize that washer mess, I used the following setup of the mentioned hardware, starting from the front:
Nut. Tiny washer. 1.5" washer. 1/2"ID medium washer(for O-ring to sit). 1.5" Washer. 3-5 tiny washers. 1.5" washer. PVC adapter. Tiny washer. Screwhead(end of screw).

The PVC stock can be triangular with a slot on top and bottom of the top pipe. You then affix a Tee for something to a bolt running through the pipe. If you add a 2" disc of PVC inside the stock the bolt will straighten out a bit. Just hook the wire around the bolt to make a telescoping priming handle.

EDIT: Also, the catch ramp will require epoxy or something. To make the coupler and ramp removable you can slip on a rubber 1.5" washer behind the 3rd 1.5" metal one. The epoxy putty will bond to the PVC and rubber, so you can swap it out for maintenance/replacement.

Edited by Curly, 27 September 2011 - 06:12 PM.

[Jilliop]

Talk to SlightlySane about 1.5" plunger tubes. I bought an R2L from him and that's what it's got, and I know he makes a lot of those.

[Buffdaddy]

Talk to SlightlySane about 1.5" plunger tubes. I bought an R2L from him and that's what it's got, and I know he makes a lot of those.

Thanks for suggestions, guys. I decided since it could fit, I'm doing 2" by 1 3/4" polycarb tubing for the barrel, and getting the parts to go with that. Updates later, I promise!

[Daniel Beaver]

What type of 1.5" plunger tube fits in a Tornado shell? They're fairly cramped, and I have a hard time believing that you can fit anything that big in there.

Edited by Daniel Beaver, 29 September 2011 - 08:46 PM.

[thedom21]

I made a polycarb ramp using just a drill and dremel. If you want pics I can get some for you.

[TxNerfer]

Fuck those fancy ramps, use epoxy putty!

[thedom21]

There are the pics.

[Buffdaddy]

Haha, thanks!

Ran across a few problems, so that project's on the shelf temporarily.