Search found 38 matches

by joestue
Sun Jun 29, 2008 1:04 am
Forum: Off-Topic Hobbies
Topic: Increase gas milage
Replies: 55
Views: 12146

OK. I am also interested in this subject and have done some research. First of all your alternator is always spinning and not always powering much so are you recovering lost energy from it spinning as long as you don't draw to much current? Second H2 and O2 burn much faster and much hotter than vap...
by joestue
Fri Jun 27, 2008 2:17 am
Forum: Off-Topic Hobbies
Topic: Increase gas milage
Replies: 55
Views: 12146

The alternator is not 90% efficient. at a good load of say 50 amps on a 90 amp rated alternator, at cruising speeds of 4000rpm (2:1 off the engine) figure about 50% overall efficiency into a 12 volt load. HHO is about 40% efficient at 2.6 volts across each cell. The engine is horrendously inefficien...
by joestue
Fri Jun 27, 2008 1:16 am
Forum: Off-Topic Hobbies
Topic: Increase gas milage
Replies: 55
Views: 12146

Last i heard about this, the hydrogen increases the burn rate, so by delaying the combustion via modifying the timing, you increase engine efficiency enough to recover the alternator load.
by joestue
Tue Jun 24, 2008 9:30 pm
Forum: Off-Topic Hobbies
Topic: Electronics people here?
Replies: 25
Views: 5681

"You need at least one EMF source."
Electromotive Force

A battery, transformer and 4 diodes, a solar cell, alternator, etc.
by joestue
Sun Jun 22, 2008 8:00 pm
Forum: Hybrid Cannons
Topic: Safety of malleable iron
Replies: 42
Views: 7766

65 psi is, well, insane. 6.5 psi is a more reasonable burst. even with someone sitting on it, and a one foot diameter circle is touching the ground, which i would imagine is reasonable, yields 113 square inches. at most 2 psi people, unless your grandma is sitting on it... edit: 30-65 kilo pascals m...
by joestue
Sat Jun 21, 2008 1:47 pm
Forum: Ammo & Parts
Topic: Pressure rated dwv?
Replies: 30
Views: 8138

"The numbers are, very roughly speaking, ten to twenty times greater than the actual working pressure rating for typical PVC1120 ASTM D2441. " and that's because the diameter ratio is ten to twenty. in the case of my infamous cannon, the diameter ratio is ~39 so if you take (4000psi/safetyfactor of ...
by joestue
Fri Jun 20, 2008 4:17 pm
Forum: Ammo & Parts
Topic: Pressure rated dwv?
Replies: 30
Views: 8138

"Perhaps you can point to a page that says typical SCH 40 PVC pipe" There is no such thing. your question about the pressure rating shows you don't understand how they rate pvc. 5600 psi burst and a 2.5 safety factor means a schedule 40, 2 inch pvc pipe will be rated at 373 psi pr=(2/diameter ratio-...
by joestue
Thu Jun 19, 2008 5:04 pm
Forum: Ammo & Parts
Topic: Pressure rated dwv?
Replies: 30
Views: 8138

I have been doing a lot of reading, and i'm not convinced even pressure rated pvc is any safer than non pressure rated pvc. Some sources indicate the difference is a safety factor of 2.0 vs. 2.5, but do your own research. There is some massive discrepancies between what constitutes pressure rated pv...
by joestue
Thu Jun 19, 2008 4:12 pm
Forum: Ammo & Parts
Topic: Pressure rated dwv?
Replies: 30
Views: 8138

sorry, i meant the inherent strength of the plastic. you need to take the diameter ratio into account, and correction factors for schedule 80 and higher. before this flame gets any bigger.... if the manufacturing specifications are blatantly false, and your pipe bursts at a pressure more in line wit...
by joestue
Wed Jun 18, 2008 4:54 pm
Forum: Ammo & Parts
Topic: Pressure rated dwv?
Replies: 30
Views: 8138

absolutely, if the manufacturer don't want to guarantee a product but is sill kind enough the give the material properties of the product, feel free to use them
by joestue
Tue Jun 17, 2008 8:51 pm
Forum: Ammo & Parts
Topic: Pressure rated dwv?
Replies: 30
Views: 8138

The PVC1120 means it is PVC type I grade 1. Hydraulic design stress of 2000 psi, or a safety factor of 2.5, industry standard. burst is 5600 psi. the only other PVC i've seen is 2116 Type II grade 1, design stress of 1000 PSI. DHW also means it is good to 140 Fahrenheit at some specific derating, i ...
by joestue
Sun Jun 15, 2008 8:14 am
Forum: Pneumatic Cannons
Topic: 6 inch coaxial
Replies: 32
Views: 8985

lol fill it with water.
by joestue
Sun Jun 15, 2008 7:56 am
Forum: Pneumatic Cannons
Topic: 6 inch coaxial
Replies: 32
Views: 8985

more like 10 shots, but i am going to have my friend destructively test it.

i was never intending at the time to go past 60-70psi!

100 is an absolute limit for the chamber.
by joestue
Sun Jun 15, 2008 7:43 am
Forum: Pneumatic Cannons
Topic: 6 inch coaxial
Replies: 32
Views: 8985

the black plastic is the barrel, the safest place for it. but you forgot about the 6 inch chamber, it's not rated. a 'wrapped' pressure vessel is extremely common, and in fact one of the only economical methods of creating large vessels, for example, 5 foot diameter, 5K psi etc. stress is always 2x ...
by joestue
Sun Jun 15, 2008 1:06 am
Forum: Pneumatic Cannons
Topic: 6 inch coaxial
Replies: 32
Views: 8985

The flat plastic reducer failed at 65 psi, i then replaced it with aluminum. The chamber is rated to 100 psi, it don't say that on the side, but the 2 inch stuff is rated to 300, so by analogy... the valve as is would hold 100 easy, the flat reducer failed around the edges, where the flat pvc meets ...