Compressor Question

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watto
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Tue Sep 25, 2007 6:19 am

I saw a hand held re-chargeable compressor that pumps only 3.4L per minute, which is pretty slow I know, but I wouldn't mind it going slow if it meant I wouldn't need a power point or to drain my cars battery. So can any maths wizards tell me how long it would take to fill a chamber thats 220cm² at 3.4L per minute?
spanerman
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Tue Sep 25, 2007 6:37 am

yuor chamber is 2.2l and the pumps output is 3.4l/m


2.2/3.4=0.64m

0.64*60=38s
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watto
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Tue Sep 25, 2007 6:42 am

spanerman wrote:yuor chamber is 2.2l and the pumps output is 3.4l/m


2.2/3.4=0.64m

0.64*60=38s
What pressure will 38s bring the chamber to.
Thanks a lot
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homedepotpro
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Tue Sep 25, 2007 8:30 am

i think its about 15psi so if his math is right it would take 228s to get to 90psi
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Fnord
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Tue Sep 25, 2007 9:12 am

Keep in mind the compressor you are suggesting is one of those emergency tire pumps and will probably die after an hour or two of work.
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watto
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Tue Sep 25, 2007 9:26 am

_Fnord wrote:Keep in mind the compressor you are suggesting is one of those emergency tire pumps and will probably die after an hour or two of work.
Yeh I'm not getting it
DeathBlade
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Tue Sep 25, 2007 10:36 am

Does your car have AC? and do you use the AC/defrost? If you have AC and dont use it you can convert it to compress air, go onto google and search for onboard air sanden (your call will most likely have a sanden rotary compressor)

I have a RV2 AC compressor in place of my stock AC for running airtools/spudguns on the trail.
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Tue Sep 25, 2007 6:02 pm

DeathBlade wrote:Does your car have AC? and do you use the AC/defrost? If you have AC and dont use it you can convert it to compress air, go onto google and search for onboard air sanden (your call will most likely have a sanden rotary compressor)

I have a RV2 AC compressor in place of my stock AC for running airtools/spudguns on the trail.
The only reason AC compressors get high pressures in cars is because they are pumping oil/free-aun(sp). They arnt very good at pumping air, it would take a long time to pump up even a tire with one.
DeathBlade
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Tue Sep 25, 2007 8:50 pm

jrrdw wrote: The only reason AC compressors get high pressures in cars is because they are pumping oil/free-aun(sp). They arnt very good at pumping air, it would take a long time to pump up even a tire with one.
In that you are wrong, you just add a oiler to the intake on a sanden, (york210/rv2 have a oil sump) and it will pump air just as well as it could R-12/134 freon, my RV2 airs up one of my 31x10.5s in well under a minute going from 0 to 30 psi. Even a small sanden or york 206 AC compressor will easily air up a large tire, continously run a impact wrench or fill a spudgun. Hundreds of offroader cant be wrong.
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watto
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Tue Sep 25, 2007 11:13 pm

DeathBlade wrote:Does your car have AC? and do you use the AC/defrost? If you have AC and dont use it you can convert it to compress air, go onto google and search for onboard air sanden (your call will most likely have a sanden rotary compressor)

I have a RV2 AC compressor in place of my stock AC for running airtools/spudguns on the trail.
I live in Australia, so believe me I NEED the aircon, LOL
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Wed Sep 26, 2007 6:57 am

DeathBlade wrote:
jrrdw wrote: The only reason AC compressors get high pressures in cars is because they are pumping oil/free-aun(sp). They arnt very good at pumping air, it would take a long time to pump up even a tire with one.
In that you are wrong, you just add a oiler to the intake on a sanden, (york210/rv2 have a oil sump) and it will pump air just as well as it could R-12/134 freon, my RV2 airs up one of my 31x10.5s in well under a minute going from 0 to 30 psi. Even a small sanden or york 206 AC compressor will easily air up a large tire, continously run a impact wrench or fill a spudgun. Hundreds of offroader cant be wrong.
Yea, i figured there would be a rebutal. At 30 psi, do you have to give the impact wrench a spin to get it going??? How long are you running that impact wrench continously, 10 seconds??? 1 more thing, in all my machanical years i,ve never even heard of hundreds of "off roaders" useing ac compressors. If they are serious off roaders, carring one of these for emergancy uses would just be dead weight, and unessisary strain on the engine. I'm not saying some people don't do it that way, but with my expearance, thats a hard way of doing it.
DeathBlade
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Wed Sep 26, 2007 1:21 pm

In your 'machanical years' wow! I like how you assume that the system is limited to 30psi and it can only run for a second. Here I'll give you some links, to try to correct your 'machanical' knowledge on the subjuct.

http://www.jedi.com/obiwan/jeep/yorkair.html
http://www.huv.com/jon/jeep/Air/index.html
http://www.webejeepin.com/Glenns_Jeep/onboard-air1.htm
http://www.tmcom.com/~tsm1/scout/faq/77onboardair.html
http://www.jeepforum.com/forum/showthread.php?t=436114

Any of the above can easily put out 5-10cfm@90psi. I can run airtools with mine with a near 100% duty cycle. If would have bothered to do a search, you would see that a compressor is quite useful and used by 'hundreds of offroaders' quite alot. When they air down tires for sand, break a part, change a tire, or even fill up there kids waterwings.
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Wed Sep 26, 2007 5:03 pm

DeathBlade wrote:In your 'machanical years' wow! I like how you assume that the system is limited to 30psi and it can only run for a second. Here I'll give you some links, to try to correct your 'machanical' knowledge on the subjuct.

http://www.jedi.com/obiwan/jeep/yorkair.html
http://www.huv.com/jon/jeep/Air/index.html
http://www.webejeepin.com/Glenns_Jeep/onboard-air1.htm
http://www.tmcom.com/~tsm1/scout/faq/77onboardair.html
http://www.jeepforum.com/forum/showthread.php?t=436114

Any of the above can easily put out 5-10cfm@90psi. I can run airtools with mine with a near 100% duty cycle. If would have bothered to do a search, you would see that a compressor is quite useful and used by 'hundreds of offroaders' quite alot. When they air down tires for sand, break a part, change a tire, or even fill up there kids waterwings.
All are modified, correct? Maby i missed you stating they are modified, if i did, sorry, my fault. I would just not like to come back and see that a fellow member sank a bunch of money into something that didn't work on the advice of another member. The sarcasisum was unnessisary. I would scream at you for it, but that would make me no better for it, and would pollute watto's thread.
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Wed Sep 26, 2007 5:45 pm

DeathBlade, I believe you did say an unmodified compressor. And JRRDW here is a pretty damn good mechanic. I've been hanging around here long enough to know that.
DeathBlade
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Wed Sep 26, 2007 6:40 pm

I'm not saying that he isn't a good mechanic, it just the way he stated it previously.
And the compressors themselves aren't modified, just whats attached to them, a tank, pressure/safety switch, and fittings etc. Example for just pumping air/filling tires/spudguns no airtool, I would (lets say I have a stock sanden AC compressor), I would have a shop vent the freon and disconnect the fittings and I would buy a set of rotolock to 1/4"-3/8"s fittings(rotolocks are the hose fitting on most AC compressors), then I would add a oiler/air filter to the intake and a fitting for the air hose to the output a quick disconnect or similar . And a new switch to the compressors clutch. This would be a simple system that could be converter back to AC with flushing out the compressor, reattaching the AC hoses and a fresh charge of R134. It wouldn't be modifying the compressor per say but modifying it application.
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