Short question topic

[jackssmirkingrevenge]

It doesn't really make sense for us, we can go higher... IIRC D_Hall played with 6000 psi at one point, I know Gippeto did some really hardcore testing too.

[farcticox1]

Yes, I posted my nerf gun on Nerfhaven, and they are saying 'woh HPA, that's dangerous', and I'm saying 'No, it's nowhere near HPA'

[jackssmirkingrevenge]

Do you expect NERF people to have a functioning sense of proportion

[farcticox1]

Not really

[Cthulhu]

I've been working on my first hybrid, and I'm getting some serious grief with the ignition.
I epoxied a spark plug into a pipe reducer fitting and threaded that on to the combustion chamber and I got it to spark with a regular barbecue igniter (one of the ones that uses batteries, not a piezo). But I still can't get ignition. Should I just give in and order a taser? Or is it more likely a mix problem?

I really jumped head first into this one

Also, has anyone experimented with using electric matches (the ones they use for model rockets) on hybrids? I feel like it would give a much more surefire chance of ignition and it's easier to make.

[jackssmirkingrevenge]

How are you filling your fuel/air mix?

[Cthulhu]

How are you filling your fuel/air mix?

syringe fueling Its worked well for me in the past but I can't even get a 1x to ignite on this.

[jimmy101]

Either you aren't actually getting a spark or your mix is wrong. Pretty much any electrical spark should ignite a correct mixture. (Though at high compression ratio's it'll take either a higher voltage or a narrower gap to get a spark.)

[jrrdw]

Either you aren't actually getting a spark or your mix is wrong. Pretty much any electrical spark should ignite a correct mixture. (Though at high compression ratio's it'll take either a higher voltage or a narrower gap to get a spark.)

Well said! :bigsmurf:

[Cthulhu]

[youtube][/youtube]

Found this neat video of a guy's solenoid artillery cannon. Anyone have any ideas on how he made that elevation adjustment wheel? Overall the sighting system is very nice and I'd like to make it on my next cannon.

[jrrdw]

This cannon was posted approx. 3 maybe 4 years ago here on Spudfiles, happy hunting. :bigsmurf:

[Alex345]

Short question! How much PSI/BAR can those clear braided hoses from the general DIY stores handle? Looking for a more flexible way to pressurize my cannon with a fridge comp at about 40bar MAX.

[jrrdw]

Pex?

[Alex345]

I don't see a max pressure stated on the website tho? it still looks rather rigid. I've seen them before in construction works. I'm currently working with 8mm OD copper tubing and brass union fittings but it's a mess and i need to tighten them so hard with a wrench that the soldering often gives or the tefloned fittings get reversed and start leaking.

[mrfoo]

ISTR PEX has a maximum pressure rating of about 10 bar at room temperature. And although it's fairly rigid, it's also flexible enough that it will "balloon".

How about a flexible from a grease gun? Commodity part, high pressure rated (400 bar or so), flexible, standardised threaded ends (1/8 BSPT, if memory serves)