SpudFiles

I decided to build a hybrid for my next gun and I just wanted to run my design by the forum.
thanks,
pat

ps. should any steel pipe work? my Lowes sells pipe that I think is sch 10.

SCH10 doesn't sound very thick at all. Would you trust a chamber made from Steel Foil 0.5mm thick just because it was made from steel?

Try and find something thicker.

MaxuS the 2nd wrote:SCH10 doesn't sound very thick at all. Would you trust a chamber made from Steel Foil 0.5mm thick just because it was made from steel?

Well, 0.5mm steel wouldn't worry me too much. UK copper pipe is usually only around 0.9mm thick, and it's not as strong as steel - so it would be similar in yield strength.
But, I went and looked, and surprisingly, SCH 10 is around twice as thick as UK copper in similar sizes, so a lot stronger than pipe I already trust almost to the ends of the earth (...well, I'm not that thick, but there are few things I would rather use.)

It might do, but as steel doesn't have the favourable failure characteristics of copper, I would suggest something much thicker would be a LOT better.

Your pressure gauge is going to receive a spike when the cannon ignites, which may break it. This can be solved by putting it on the other side of that ball valve that's on your meter. You may also want to consider moving the spark into the chamber. Other than that, it looks good.

yeah that spark would be useless:)

what are you planning to use for ignition?

if it has a decent amount of power (stun gun, electric bbq, etc.) , i suggest you go with 2 plugs along the chamber for better performance

I was planning on using a bbq lighter. where do you guys get your steel pipe. I knew something was up when it was the same price as pvc.

they sell it at any hardware store up to 2in if you live in the us.

Some say one could use Sch80 for a hybrid, but only up to 4x. I wouldn't know as I've never tried it. This may be a thought if you can't find the steel (and 4x is pretty impressive, especially if you've never experienced a hybrid).

Never use sch80 ibn a hybrid there have been multiple failures with them espesially at the unions.
Check the failure analisis tread there is a hybrid there that blew at 2x im not sure it may have been 3x.

SCH 80 should be fine to use up to about 20x, just as long as it's steel

Well sch 80 pvc has been used, dont forget about the hybrid on advancedspuds.com as shown here

But personally, i would go with steel, and never use pvc.

pat123 wrote:I was planning on using a bbq lighter

piezo or electric?

The peazo ones dont provide enough ompff to ignite it very affectively it has been done before but I would recommend a more powerful igniton like an electric BBQ ignitor or prefferable a stun gun.

thats why I'm asking lol. because to use a spark plug on a regular piezo is ridiculous because the spark you get from it is less likely to ignite the fuel than using flint and steel by hand.
So if you are planning on using a piezo, please don't. especially not for a hybrid. For $15 more, you can get an electric one that rarely miss fires and won't ware down (just need to replace batteries).