SpudFiles

One short question: my tazer gives a 3cm spark at normal pressure, how high I can go?
As soon as I find a good burst disc, mix of 20 is coming
Hybrids ROCKs

30x should be within your grasp assuming you have a tiny enough spark gap

Also, good to see you illustrate the syringe fuelling on your video.

oops, forgot to mention, my ignition plug is 1mm.
Yap syringe fueling is the most reliable and simple way to do it, yet accurate

Great job !

You too Petitlu !

Thank you!
this is our first hybrid to both, cool!

Might be worth looking into some of pressure ratings before going too high in the mixes.
There are larger volumes at play here and/or less material than most of the high mix hybrids that have been done so far.
And it's probably a good exercise anyway.


Haha, and for the higher mixes, might be worth clamping down the canon in some way


Nice work.

PCGUY, can we hide a certain users posts on a certain board? As some raging anti-hybrid members spam pointless messages.

al-xg wrote:Haha, and for the higher mixes, might be worth clamping down the canon in some way

Seconded, maybe on a wheeled table

Did more tests today, but had a lot of problems with burst disc

[youtube][/youtube]
I was hoping to go 10x, but nothing holds that pressure. Also, 1mm spark at 10bar can´t be heard, so I ´m not sure if the spark is working, but it should.
Ended up using 7x, the first try was a success, but when I attached the barrel, the burst disc didn´t break I was using aluminium foil, the first few layers broke, the rest were almost.

good video!
I find that the rupture disks are not well cut while shooting.
they are pressed into the fitting?
I used the steel of soda and the disc is well cut

You mean soda cans? lateral or the base?

As to appropriate burst disk material, wyz: aluminum foil will work just fine. The number of layers required can be assumed to scale linearly with the desired rupture pressure. I don't see what you're using as a holder for the burst disk. If it's a 1/2" union, rupture pressure should be 10-20psi / layer for standard thickness aluminum foil. Try a 32 layer disk for 10X, for starters.

The required spark gap length scales approximately inversely with the chamber pressure (for low pressure, at least). If your rig could tolerate a 10mm gap at atmospheric pressure with no arcing across in places it wasn't supposed to, there shouldn't be any problem with a 1mm gap at 10X. I never had the luxury of such long gap. When I used HV ignition (which wasn't all that often in my later hybrids due to issues with high voltage and long wires laying on the ground), the gap was usually less than 0.3mm for a 10X mix (with a capacitor discharge driven ignition coil providing the HV pulse).

Lateral!
I stick the disc in an iron washer with a little super glue, a flat seal is against the washer, perfect seal!

Can soda or can "1664"