SpudFiles

A few questions,

1. Is aluminum something worth making my next hybrid out of?
2. Am I better off (and/or safer off) using something like stainless steel? I was planning on making the chamber out of a solid rod of stock, and bore it out, leaving one end already closed off and an extra large wall thickness.
3. Would it be better (also cheaper) to simply buy a section of aluminum pipe and just weld on a cap?
4. I'm probably gonna be running it at a 2x mix, just because.
5. If I wanted to run it at say a 6x mix though, what would be my best option for material.

Thanks I feel like I'm forgetting something though, I'll have more questions I'm sure.

And yeah, I'm back too, it's been a while.

1.Any metal with decent stregth is strong enough and aluminum has nice acstetics and decent stregth and doesnt cost to much so yeah Id say it would be worth it .
2.It doesnt matter, eigther way you wont be comprimising saftey until you get to 8x or 9x(some members may dissagree, that is fine)
3.?
4.Why would you waste a hybrid made of metal with such low mixes you are completely safe, no chance of explosion all the way up to 6x although higher would still be considered safe.
5.Any metal with reasonable strength

Go for it, just make sure you keep the walls nice and thick.
Have you got any rough dimentions you were planning on using? Even relatively thin walled Aluminium can take pretty decent pressure- i think 2" with 1/8th walls fails at around 2000 psi (6061).

Best Cheap and Easy way to go about this would be to get some SCH40 Aluminum weld your cap or whatever on it because that weld is gonna be stronger than the original metal if you know how to weld. Doing it that way is gonna keep your cost down while still giving you a great amount of strength.

Edit wtf this post belonged in another thread.

Ignore it

I would use steel as it easier to weld. A good property of aluminium is that it is flexible and elastic. Steel has a high strenght and has less flexibility. I would say just use steel as it is safer, unless you are building a lightweight cannon. Another factor btw is temperature, steel can take higher tempertures as aluminium can take lower temperatures (below freezing'') bc of its higher elasticity. Btw check how the pipe is manufactored> pipes that are drilled from a massive cylinder are less strong'' then pipes that are rolled or extruded. I think most aluminium pipes are drilled. Some of the things I said could be a bit off as I simplified my explanation:)

Aluminum and stianless are both expensive metals and unless you have the proper welding equipment you won't be able to weld them either... I think your better off sticking with steel... unless you have a bunch of stianless or aluminum stock laying around.

Jared Haehnel wrote:Aluminum and stianless are both expensive metals and unless you have the proper welding equipment you won't be able to weld them either... I think your better off sticking with steel... unless you have a bunch of stianless or aluminum stock laying around.

Oh yeah right stainless doesnt have the right carbon level to weld with simple welding machines, thats right.

BigGrib wrote:Best Cheap and Easy way to go about this would be to get some SCH40 Aluminum weld your cap or whatever on it because that weld is gonna be stronger than the original metal if you know how to weld.

Ummm.... You mind backing that up; or at least qualifying it?

The most common structural aluminum out there is 6061 T6. See that T6? It's a heat treating process. You weld on it and it you've drastically reduced it's strength. So yeah, maybe the weld is stronger than the vessel, but since you've destroyed the heat treatment that's not saying much.

Yes, you can always re-treat it to bring the whole mess back up to a T6 specification, but I'm going to go way out on a limb and say that damned few of the people around here will have the required knowledge and capabilities to do that.

Now obviously not all aluminum is of the 6061 T6 variety, but that's the most common and the point is that unless you're going to qualify your statements it's pretty wreckless to run around implying that welding aluminum results in a stronger item than you started with. In certain circumstances, it may, but to make generalizations along these lines is - IMHO - careless at best; dangerously ignorant at worst.

Threading is the way to go. Yes, I know that is not an easy thing... just saying, it's not that expensive to find a machine shop to make a couple parts that you can use as a basis for more experiments.
Don't fool with your life. Dangerous shit we play with. I almost got killed once, almost lost my toes another time. Be safe whatever you do.

I've ended up going out and just buying some steel pipe from my local Lowes.

Yay or Nay? All connections are threaded and then welded.


Now it's been a while since I've used this here fuel tool, I need some assistance in figuring some things out.

I wanna run my gun at a 2x-4x mix. I can't decide. Also, I don't know what to input aside from how big the chamber is into the fueltool. Any help?


Edit: Shitty Paint Drawing: Basically I don't know how big the meter pipe needs to be, and it's more of a bunch of elbows and fittings so I was just gonna measure its volume with water until I got it right. But I don't know how big to make it.

2" SCH 40 steel was tested up to 11x by _Fnord.

And don't use a fuel tool for hybrid metering. Just do the calcs yourself, as fuel tools don't compensate properly for hybrids. Check out the first post of the "HYBRID FUELING 101" thread for all you need to know.

And use oil for your liquid volume measurements. I caused some pretty bad rusting in a 4" schedule 40 steel pipe by measuring its volume with water (lucky I still have about 15 feet of the stuff handy).

Also, you should design your meter so that the air flows in behind the propane inlet - check out SB15's hybrids.

Quite a bit has changed since you used to frequent this forum.

hahaha... woops DYI, i used water, oh well i blew it all out with air and tried to dry it as best as possible, hope it doesn't come back to slap me in the face.

Yes DYI, alot has changed. For the most part I like though, so good job everyone.

Edit: Got me curious, what point does oil serve versus water in measuring up my gun?

Edit2: Shitty Paint Drawings, part 2:




Edit3: Went and spent quite a lot more time than I should have trying to figure out a number for how much volume the propane meter should contain to get me to the proper ratio. The gears are so rusty.

Any help? ~500-550mL chamber, plan to run at 3x or 4x mix (if deemed safe)

Recently, several calculators and programs have been set up in which some do hybrid calculations. just look in any of the recent topics for calculators/programs. I made my own in Java