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Posted: Wed Jan 02, 2008 10:20 pm
by homedepotpro
looks good, whats your compression ratio, and what did you use as a bumper.

Posted: Wed Jan 02, 2008 10:24 pm
by cwazy1
compression ratio, i have no idea. its a 16" shaft/drive with a 36" body,

well i have screws/bolts stopping it and i just placed an old sock on them, once it fails, then i'll change it..lol

EDIT: cool, i have a red star now.

Posted: Wed Jan 02, 2008 10:26 pm
by elitesniper
wow thats cool cwazy1 mabey you can put a gauge on it to see how many psi its creates when you jump, but i think it varies on how much a person weights

Posted: Wed Jan 02, 2008 10:36 pm
by Atlantis
If you do put a gauge put a check valve before it so it stays up there.

Posted: Wed Jan 02, 2008 10:49 pm
by homedepotpro
when precompressed to 25 psi and fully depressed at the bottom of a bounces it creates 100psi. mine has a 4-1 compression ratio. it makes calculating the pressure pretty easy.

Posted: Wed Jan 02, 2008 11:06 pm
by cwazy1
does 4 to 1 compression ratio mean that your length of the "body" is 4x the length of the shaft?

so like a 4 foot body and a 1 foot shaft thing?

and so for mine, would i have a 2.2-1 ratio? so if i precompressed it to say 30psi, i would get 60psi? cuz that doesnt sound right.

Posted: Wed Jan 02, 2008 11:12 pm
by homedepotpro
no thats what i got. but it actually might have a lower ratio than that because of the dead space at the top in your handle. the ratio is the volume of the cylinder when full y expanded to the cylinder when it is fully compressed. seems like you rush this project and didnt crunch the numbers.

Posted: Wed Jan 02, 2008 11:44 pm
by hi
does it work if you don't pre compress it? how long will it work before you have to compress it again?

Posted: Thu Jan 03, 2008 12:06 am
by homedepotpro
hi wrote:does it work if you don't pre compress it? how long will it work before you have to compress it again?
-not really
-i dont know yet, i havent had enough testing

Posted: Thu Jan 03, 2008 12:29 am
by cwazy1
ohhh, okay i know what you mean.

well im adding a different foot petal, so this time, i can do some number calculations. is there a perfect ratio?
does it work if you don't pre compress it? how long will it work before you have to compress it again?
it "works" if you define working as it moves up and down, but you will need a long shaft thats close to the length of your body in order to get enough pressure build in your body in order for it to push you back up.

Posted: Thu Jan 03, 2008 12:52 am
by homedepotpro
i dont know if there is a "idea" ratio, but im pretty sure it depents on the a multitude of factors. the real one has a 3:1 ratio but it also has a 3'' cylinder.

Posted: Thu Jan 03, 2008 12:57 am
by cwazy1
hmm yeah, im thinking 3-1 as well. 3foot long body with a 2 foot shaft but mines 2" pipe. hmm trickty. i'll play with it.

Posted: Thu Jan 03, 2008 7:33 am
by jrrdw
homedepotpro wrote: btw jrrdw, i rebuilt the pegs, i knew those old ones wouldnt last.
I'm glad to hear that. How did you attach them? They looked like shelf braces.

Sooooooo, who's gonna win the race to get the first video up and posted?

Shhhhhhh! Thats a challenge!

Posted: Thu Jan 03, 2008 7:17 pm
by cwazy1
lol

teamwork, not competition. not yet at least.

so hey HDP, i rebuilt mine with a 3-1 ratio, i redid the pegs with a 2" cross cut down the middle then scrapped with hose clamps and pvc glue. should hold nicely.

have you got to fully test yours yet? mine is drying again.

Posted: Thu Jan 03, 2008 9:12 pm
by homedepotpro
yes i have and id have to say im impressed. it is different than any other pogo stick ive jumped on. its hard at first because the compression stroke is so long but i got used to it. i was getting about 1.5' of air at 25psi and i wasnt even bottomed out yet.