Search found 194 matches

by Cthulhu
Thu Jul 02, 2020 9:18 pm
Forum: Ammo & Parts
Topic: Brass as the foundation of a projectile?
Replies: 6
Views: 15821

Re: Brass as the foundation of a projectile?

Doc j wrote:
Thu Jul 02, 2020 12:03 am
How would hollow cylinder and sabot go.
Someone's thought about it.
I have wondered about this too, particularly with a helical vane inside the hollow to facilitate rifle stabilization in a smooth bore barrel.
by Cthulhu
Thu May 07, 2020 2:54 pm
Forum: Pneumatic Cannons
Topic: is my valve good?
Replies: 3
Views: 3654

Re: is my valve good?

It's more work but if you really wanna go electronic you could make a piston valve that is vented with an electronic solenoid.
Also look into sprinkler valves that are modified for pneumatic action, they also work with just the push of a button, but without having to worry about batteries.
by Cthulhu
Sat Apr 25, 2020 1:39 pm
Forum: Combustion Cannons
Topic: Propane fuelmix problem solved.
Replies: 1
Views: 2893

Re: Propane fuelmix problem solved.

This is pretty interesting, is there any loss in performance from the valve needing to close during combustion rather than before? And how about safety? I'm sure some gas leaks from the check valve before combustion, is there any chance the check valve won't close before the reaction hits the outsid...
by Cthulhu
Sun Feb 23, 2020 9:44 pm
Forum: Combustion Cannons
Topic: Shooting various materials with my spud gun
Replies: 3
Views: 12745

Re: Shooting various materials with my spud gun

Fun video, I missed seeing content like this.
by Cthulhu
Mon Feb 03, 2020 4:51 pm
Forum: General How-To & Discussion
Topic: Taking examples from nature: hydropneumatic spuds
Replies: 3
Views: 4480

Re: Taking examples from nature: hydropneumatic spuds

I've never been good at physics but wouldn't you want a more viscous liquid so that it can impart more momentum to the projectile? Something like a syrupy liquid under high pressure could impart a lot of force
by Cthulhu
Sun Feb 02, 2020 7:16 pm
Forum: General How-To & Discussion
Topic: Taking examples from nature: hydropneumatic spuds
Replies: 3
Views: 4480

Taking examples from nature: hydropneumatic spuds

So my college education and personal interests have started making me get into mycology, and I read about a type of mold called pilobolus which fires it's sporangium at astounding rates of velocity by pressurizing water into a vesicle until the connection between the vesicle and the sporangium pops ...
by Cthulhu
Sat Dec 28, 2019 10:59 pm
Forum: General How-To & Discussion
Topic: Short question topic
Replies: 1502
Views: 657679

Re: Short question topic

I find it a bit complicated to electrically insulate the high voltage cables from the sparks. At times it seems that only space can make the spark not jump where she wants. :? What materials do you use to insulate? Is there any special type of cable for this purpose? They tell me from these sides t...
by Cthulhu
Wed Dec 25, 2019 11:03 am
Forum: Hybrid Cannons
Topic: Single pumping hybrid, "Strong Boy"
Replies: 59
Views: 109419

Re: Single pumping hybrid, "Strong Boy"

I'm really impressed by this! It's such a nice sleek design!
How did you make the O-ring that seals against the projectile and what stops the compression from the piston from pushing it past the o-ring?
How does metering work with that cut down syringe?
I can't wait to see more of this!
by Cthulhu
Sun Dec 22, 2019 3:39 pm
Forum: General How-To & Discussion
Topic: "In the world of spuds today"
Replies: 2461
Views: 1785509

Re: "In the world of spuds today"

Got some practice with the welder by making a tool for the lathe. I've been needing a tool rest more suited towards the carbide tooling I use so I welded this together. The welds have really bad porosity but I believe that is because I was holding the gun at the wrong angle and I wasn't moving consi...
by Cthulhu
Mon Dec 02, 2019 9:06 pm
Forum: General How-To & Discussion
Topic: "In the world of spuds today"
Replies: 2461
Views: 1785509

Re: "In the world of spuds today"

I wish! I had to settle for fluxcore, which is basically stick welding but the electrode is in a wire form. Luckily it was less than 150 bucks on black friday though
by Cthulhu
Sun Dec 01, 2019 3:22 pm
Forum: General How-To & Discussion
Topic: "In the world of spuds today"
Replies: 2461
Views: 1785509

Re: "In the world of spuds today"

Just bought my first welder, looking forward to moving on from pvc! Now I have to learn to weld properly lmao What welding processes do you guys use? I picked up a titanium flux 125 on black friday, I was originally gonna try stick but the learning curve was intimidating and it didn't seem well suit...
by Cthulhu
Fri Nov 29, 2019 1:54 am
Forum: Pneumatic Cannons
Topic: preloaded pneumatic cartridge
Replies: 338
Views: 226987

Re: preloaded pneumatic cartridge

Cartridges seem to be making me more excited than they should nowadays... What's your opinion on this Jack? It's probably a bad idea but I was thinking about those old wax dueling pistols and I was wondering how a company could make one time use disposable cartridges to fire wax bullets (that would ...
by Cthulhu
Sat Nov 16, 2019 12:42 am
Forum: Combustion Cannons
Topic: A new look at combustion cartridge Spud guns
Replies: 25
Views: 15297

Re: A new look at combustion cartridge Spud guns

Ok so being the stubborn guy that I am, I'm back at this again. This time I have multiple successful combustion guns under my belt and I actually know how to use HGDT :lol: Here's a really crappy animation I made showing my idea (sorry for the bad lighting and the rapid speed, still learning): [yout...
by Cthulhu
Fri Nov 15, 2019 1:05 pm
Forum: General How-To & Discussion
Topic: Short question topic
Replies: 1502
Views: 657679

Re: Short question topic

hahaha, alright. I always feel bad when I do that and my ideas turn into a pipe dream :oops:
by Cthulhu
Thu Nov 14, 2019 1:12 pm
Forum: General How-To & Discussion
Topic: Short question topic
Replies: 1502
Views: 657679

Re: Short question topic

You should be able to add as many layers of foil as it takes to hold a wide range of pressures. What are the dimensions of that thing? Also, I wouldn't want to mess with 8 screws every time I wanted to shoot the cannon. Can you use a cam-lock instead? What mixtures you going to run? The OD is 2.067...