Clear PVC? - At McMaster

[Rook]

McMaster sells clear PVC of all shapes and sizes. It's significantly more expensive (a 4' section of 3" PVC is around $65). However, it may have some use. You could get a segment with a small diameter and connect it to a PC/Reservoir, and make a gauge.

Here is my idea:



A 4' segment 1/2" clear PVC is less than $10, and you can get smaller diameters for less than that.

I know some of you are probably wondering if it withstands pressure: it does. It says it can hold ~300psi.

Sorry if this idea has been brought up before. I don't think it has.

[SSCBen]

Nice find. That water level gauge idea is a good one. I'm considering trying that sometime this summer... just need to get the time to do it! No one's tried clear PVC pipe in homemade water guns to the best of my knowledge.

I think you should mention however that the pressure ratings depend on which pipe is chosen. Larger diameters have lower pressure ratings. The 3 inch pipe you mentioned before only has a pressure rating of 130 PSI, which will be derated by temperature as well as the use of fittings. I doubt anything really bad will happen from using it because those ratings are already conservative, but I would prefer the use of pipe with notably higher pressure ratings. Good design does matter and part of good design is adding fail safes (they make pop-safety valves that should be on any system where you have doubts about it's ability to hold pressure). So I think you get a safer and better deal from regular PVC.

McMaster-Carr seems to overprice this product. I've seen it used before in homemade Nerf guns. Then again, from the other sites I've seen, you can't order unless it's a huge segment of 10 feet. McMaster-Carr at least gives you a little flexibility, but the shipping costs are going to be huge.

The use of smaller diameter pipe probably is the best use for clear PVC pipe for us, unless you're rich.

[isoaker]

hehe.. neat design! Ben knows his stuff on PVC; me, I've always been given the impression that clear plastics tends to be more brittle than semi-clear and/or opaque, thus have a generally lower maximum pressure rating.

PVC aside, while the fill gauge design on the PC is neat, I'm not too sure about its overall battle practicality. Typically, when I use a soaker, I gauge pressure/water remaining by both weight and stream performance. The only time I use pressure or fill gauges is when prepumping soakers like the XP110 or XP310 where the gauge lets me get an idea on how much air I've pushed in. Additionally, I've got two concerns on the side-fill-gauge design: i) it adds an added bit of complexity to the design, adding in another T-joint between the PC and the nozzle; and ii) unless it is positioned right beside the PC, a thin, clear PVC tube sticking upwards unshielded is more likely to be hit/snapped by accident.

Idea for a fill gauge: put a small, decently strong magnet on a guided float inside the PC before you seal the end cap; on the outside, put a ball bearing within a clear-plastic casing. As the float inside moves up, the ball-bearing on the outside will slide up the side of the PC. Guides would be attached by either glue and/or waterproof tape. The ballbearing must be steel, iron, or something that is attracted by the magnet. The movement of the magnet and ball-bearing should be tested before the PC is sealed. Preferably, a screen should be placed at the bottom of the PC just in case the magnet/float system does get detached from the inside of the PC to prevent it from entering the tubing or being launched out the nozzle as a projectile... hmm.. yeah... my design is more complicated to build and has the problem if the magnet gets stuck or gets loose... I'll think on it a little more...

[HBWW]

I agree with iSoaker, though I haven't used seperate firing chamber air pressure guns that much and haven't used the pressure gauges to find how much air I'm pumping in. However, I can usually go without a pressure gauge, though it's definately better if you're not the tap shooting type or if you're using guns that have high outputs and low shot times.

[SilentGuy]

Definitely a neat idea--the smaller diameter by using a gauge instead of the whole PC being clear allows for greater pressures and lower price. Nice!

However, I'd be more inclined towards an actual pressure gauge given the choice.

[Croc]

Is this the same stuff as PETG, or is it some other thing like it? That looks similar to the PETG that most Nerfers use to modify barrels.

[SilentGuy]

Is this the same stuff as PETG, or is it some other thing like it? That looks similar to the PETG that most Nerfers use to modify barrels.

Nope. PETG sounds like it's mainly polyethelene polymers. PVC is polyvinyl chloride. I don't even think PETG can take pressures, but I might be wrong.