Silver Bullet

[Ben]

I'm not quite sure where those pressure numbers come from. The tube can generate about 35 PSI, which is about 10 PSI more than the CPS 2000 reportedly gets, but it doesn't have as much power. I've used those tubes before and they're comparable to the high end CPS blasters like the CPS 1500. They'd be fine. Why do you think I suggested them? If you want more power, but a tube to layer over that one and then buy a bunch of bike inner tubes.

Also, remember that while a narrower ID might make more pressure, the flow will be severely limited by the narrow ID. You can put a larger barb in smaller tubing, but you only can increase the diameter by perhaps 25% before it becomes too difficult. The tube I suggested using has a 3/8 inch ID and I've used 1/2 inch barbs in there. 5/8 inch barbs likely can be used as well and I would highly suggest their use. Anything larger will be hard to do. The tube I suggested is a good combination of pressure, volume, flow, and upgradability.

I have thought of several ideas to make putting a larger barb inside of LRT possible, but all I have tried didn't work. I am sure eventually someone will find a good way to put a larger barb in a smaller tube.

With all that being said I plan on trying some of those tubes they rate at 80 PSI or more next year. I've asked LRT manufacturers about the prices of the thicker tubes with larger IDs and they're out of our league unless someone makes a bulk order.

Edit: Now that I'm taking a look at the various options at McMaster-Carr for latex rubber, I think a homemade Hydropower system would be a very viable option. Higher flow is possible at higher pressures. The rubber would be very expensive ($40 for a 6 inch by 6 inch 1/2 inch thick sheet), but it would be very powerful. They sell gaskets that could be used with this at most hardware stores. I think I'll try this out soon, though, I post stuff like this so that someone could give it a try before me. Saves me money.

[WaterWolf]

Thanks for the help.
For the layering, do you streatch one lenghth of the same type of tubing over another, or do you have to buy a wider ID tube to go over the first?
Basic question is, do I need to buy different sizes of tubing for layers?
If so, what sizes would you suggest for those?

I think I'll go with the 3/8" ID, 3/4" OD, 3/16" Wall, Opaque Black to start with like you said.

[Ben]

Get the 1/4 inch wall 1 inch inner diameter tube. You can slide it easily over the other tube. A significant power boost without much effort. The power should be very similar to the CPS 2000 from what I have been told about this combination. Bike tubes over that of course would increase the power further.

I did make plans for a device that will aid in layering tubes that are more similarly sized before, but I sadly never made it. That's another thing for the to-do list. This device would make stacking tubes that would otherwise be too difficult very possible. It also would make putting a larger barb in fairly easy.

[Silence]

The problem with Hydro Power is that even smaller bladders will have hundreds (maybe even thousands?) of pounds of force. You need a strong frame with lots of screws (which mean you'll spend a lot of time on maintenance), and smaller power bladders for a better screws-to-force ratio.

Good thinking though...I'd like to see a homemade Hydro Power system too. But for high-level systems, you can't beat constant air pressure.

[WaterWolf]

A 1-1/2 inch thick PC before even adding bike tubes?
Wow, I hadn't realized quite how much rubber is used in a CPH.
No problem for me, just surprising.

What about the bike inner-tubes, should I use 1-1/2 ID ones or a different size?

Sorry if these seem like a lot of questions, but you and Drench are really some of the only ones with much experience in the field of CPHs and who are still live on the forums.

[Ben]

Originally Posted by SilentGuy

The problem with Hydro Power is that even smaller bladders will have hundreds (maybe even thousands?) of pounds of force. You need a strong frame with lots of screws (which mean you'll spend a lot of time on maintenance), and smaller power bladders for a better screws-to-force ratio.

It's worth experimenting in. PVC flanges might be strong enough and would be a good start. They only have 4 screws sadly. That might be their biggest weakness.

[WaterWolf]

Someone that just joined our team (who seems like a promising engineer) came up with this idea, built a working model to test on his garden hose and found that it worked amazingly well.

Just after the valve, place an equal diameter cylinder of PVC.

Fill this with lots of straws that have been cut down to size.

Put a reducer on after the straws.

When the water flows out the nozzle and through what I'm referring to as the "Inline-Straw-Nozzle", the water slides through the many narrow tubes and any turbulence that the water has gone through is immediately corrected for.

When he built a working model and tested it, the water stayed as a perfect beam throughout its entire flight. Practically no drips or spray.
At long distances, the beam would run into more air-resistance and spread out some, but its quality would still be greatly improved. The range of a gun might even see a boost, since cleaner beams cut through the air more easily.

He is going to be working some more with this design, to perfect it in time for its addition to the Silver-Bullet. It could also be added-on to practicaly any beam-homemade or modified stock soaker out there.

[Ben]

That's good news. I'm interested in how he got the straws to work well. I've used straws before and they might have improved stream integrity, but enough of them shot out the nozzle to make them less than useful.

[WaterWolf]

This is a different system than I have heard of before.

Rather than sticking one straw in the nozzle, you have a wide tube full of them before any reduction in stream size.

Not sure what he did on his, but we discussed different methods of keeping them, in such as a metal screen or just gluing the straws together. Since the straw walls are so thin, there would be very little resistance to the water, so stream speed shouldn't be affected much.

[Ben]

That's what I did. It was described in the original APH guide, but later removed due to the problem of the straws shooting out. A metal screen would solve the problem.

With that being said, I saw no noticeable increase in range, so I saw no reason to keep it in the design. Perhaps further testing is needed to determine whether or not they help, but from my current understanding, the straws only help systems that have a certain level of turbulence already.

[WaterWolf]

V 0.6.7



I've cleaned up the back section and (for a more compact set-up) moved the pump to an under-cover layout, so that your hand is better able to support the weight of the gun when you're pumping as-well as firing.
(Don't worry, I've still got it planned such that the PC cover is field-strippable.)

I've also made the pump into a tracked version, since I've recently been doing some experimenting with those and would like to try and have one on the Silver-Bullet.

The one problem with pump placement as it is now, is that you have to reach around the reservoirs. But I built a mock-model and found that my arm tended to be oriented that way direction anyhow.


@Ben:
The image inserts aren't working for me, when I try to use it the text doesn't seem to be registered as code.

[Ben]

You didn't type in the http:// part of the URL.

[WaterWolf]

Thanks.
So, what do you think of this version?
It looks like the cleanest design yet, though I have a few doubts on the pump placement. I'll experiment more with configuration on that once I get the parts (which should be fairly soon).

[DX]

You might want to have the reservoirs fill from the back rather than the top. The pc also looks huge compared the reservoirs, they'll drain really quickly. The pump placement looks fine as long as your arm clears the near reservoir.

[WaterWolf]

The PC will carry aproximatly 1200 ml (Using some caluculations Ben gave me), reservoirs together will hold 4000 ml.

I think I made the LRT look too big in this model.
How wide does a fully layered LRT get when expanded?