Nasty mould after water ans sugar shots.

[microman171]

Hey Guys,

Been a while since I was on here! Before I left I built the Bazookair cannon, the Bad Ass Kiwi Co-Axial.

I have fired all sorts of things from the barrel, including sugar. Being a pneumatic, it is easier to fire a larder range of things.

Sugar, water, and time = mould. I don't know what mould does to PVC. Does it make it more brittle?

And how about UV exposure? I know that makes it more brittle, but does it affect the pressure rating?

I'm not too keen on building another cannon for cost reasons, so would love to fix up this one. I will have learnt my lesson from the sugar xD.


Thanks,

Microman171

[jackssmirkingrevenge]

Being organic, I doubt mould would have any effect on PVC. As to UV exposure, thay would tend to weaken the pipe.

Being a pneumatic, it is easier to fire a larder range of things.

Hah! invisible pun

[microman171]

Hah! Larder range... Oops.

So will this thing still be safe to use? It is class E and F (200+PSI).

[jackssmirkingrevenge]

It's hard to tell, depends on the level of exposure. I wouldn't trust it to high pressure.

[microman171]

Hmm, would I notice any discolouration? The pipe is still nice and white.

[jackssmirkingrevenge]

It usually tends to go a bit yellow. Was it exposed to direct sunlight though?

[microman171]

Not that I know of, more just sat in a garage in the light for a long time.

[Biopyro]

Was it outside in the sun or was the exposure through a window?

[Brian the brain]

I wouldn't worry about the mould.

Would people use PVC for wastewater if that were a problem?

sunlight is a problem.
Try to hydrotest it.
Fill 'er up with water all the way and then apply airpressure to it.
Water holds a lot less energy under pressure as it can't really be compressed, so when it fails it's no real problem safetywise.

Hydrotest it to it's rating and use it below...

[microman171]

Thanks for the info guys =) The light was ambient, not direct. So I'm guessing the pipe will be perfectly fine. I will give it a good hydro test before using it though.

Good to hear about the mould thing. I wasn't sure if it would affect the pressure rating or not. Waste pipe doesn't need to hold pressure?

[Brian the brain]

No it doesn't.

but it needs to ..well..function..for years without leaking..without it being " eaten" by mould..
If mould would damage it, we would never use it.

[microman171]

Cool, glad to hear my gun should still be good =)