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Posted: Thu Aug 26, 2010 11:18 pm
by Gippeto
Gun Freak wrote:It depends on how much you weigh. If you weigh 100 pounds then it can do roughly 314 psi, and if you weigh 200 pounds then it can do over 600 psi. I would guess you weight about 150 pounds so probably an absolute max of 450 psi.

Your math is off somewhere.....or I should stop drinking...one or the other. :occasion5:

1" copper has an id of between .995" (Type K) and 1.055" (Type M).

Using a 1" as a rough average, the area of the piston head would be .785in.sq. ( A = pi *r*r)

Psi = pounds force / square inches, so...

200 lbs / .785in.sq. = 254.8psi.

Posted: Fri Aug 27, 2010 5:06 pm
by Gun Freak
My bad! Stupid math, I used the diameter instead of the radius. :tongue3: Sorry Lnl and Gippeto.

Posted: Fri Aug 27, 2010 6:07 pm
by Lockednloaded
.957 is the ID of 1" SCH 80 pipe, could i reach 300 psi if i weigh 150 pounds?

Posted: Fri Aug 27, 2010 6:32 pm
by Gippeto
The required information to work it out is in my previous post..... :?


Hear the sound of the spoon...."Clink".... :roll:

~208psi without "jumping" on it.

Posted: Fri Aug 27, 2010 6:49 pm
by inonickname
By the way, don't use PVC as a pump cylinder locked. Not only does it lack the structural strength of a lot of metal ones, it's plastic, and thus will be susceptible to softening due to heat created by compressing the gasses.

Posted: Fri Aug 27, 2010 6:58 pm
by Lockednloaded
sorry gippeto, wasn't really paying close attention...

inon, i totally forgot about those factors, but this pump wouldn't be built until at least christmas. I've got some time to figure things out

Posted: Fri Aug 27, 2010 10:01 pm
by Mr.Sandman
Why not search the classifieds, and buy a cheap fridge for like 20 bucks, salvage the compressor and take the refrigerator to the landfill? Very simple and allows you to pump to higher pressures faster and safer. There is TONS of information about using fridge compressors on these forums, including how to's, modifications, and tips on maintaining them.

Posted: Fri Aug 27, 2010 10:06 pm
by BeaverRat
BeaverRat wrote:Thanks guys, I decided to order the serfas pump, I only need to be able to reach 250 with that one. For the higher pressures, I have a fridge pump in the making.
Hmm