This is a rant against marketing hype run amok.
Seems I'm always getting a flat tire on one vehicle or another, and waiting on a slow 12v air compressor. When you go to buy a portable compressor, you read impressive PSI output: "250 PSI!" and even "Produces a fantastic 300 PSI!". Well, maybe they will actually produce those stratospheric and dangerous pressures. But why? This is always at the expense of VOLUME, which is much more useful. Why not make a truly useful portable compressor. Make one with a man-sized piston instead of a thimble sized piston. Trade PSI for volume. Match the piston and motor to produce 35 PSI at the highest possible volume without drawing excessively high amps. Why wait 10 minutes in the freezing cold for a tiny piston to fill your tire when a bigger piston pump may only take 30-45 seconds? It all went wrong when these little compressors first came out. The manufacturer used PSI as the measuring stick instead of CFM (cubic feet per minute) as they should have. The poor average schmuck keeps on choosing the higher pressure pumps, and the crummy slow pumps are perpetuated.-- bobad, Jun 19 2004 A faster alternative http://www.air-up.com/4wd.htmlBetter than your shop compressor at home... [Custardguts, Nov 22 2007] Cool, you could use it to explode people.-- harderthanjesus, Jun 19 2004 //Why 35 PSI? I need 40+, even 50.//
Then use a high pressure pump. They're fine fir bike tires.
//Though I certainly sympathize with your position, a compressor with a "man-sized" //
I don't think replacing a 1" piston with a 2" piston (for example) would take up significantly more room. However, it will put out 4X the volume at a given stroke and RPM.-- bobad, Jun 19 2004 Jeeze, I know that bike tires need from 45-80 PSI, but I've never heard of an automobile tire that takes over 32PSI. Even going from a 250 psi pump to a 50 PSI pump could increase the volume by a great amount.
Rating on portable compressors are on the order of .1 CFM. (they're usually hidden) Even a .5 HP motor pulling 30a could probably get you over 1 CFM. It's very do-able. There's no demand because consumers think astronomically high pressure is the holy grail.
I've looked high and low for a faster pump. I simply can not fine one.
Oh well, no big deal. I just like to peck away at life's little annoyances.-- bobad, Jun 19 2004 Road tires on racing bicycles can sometimes handle in excess of 100 PSI, but I've never heard of anything running in the 250 range.-- 5th Earth, Jun 19 2004 I really don't think these compressor makers are responding to consumer demand and driving up the pressure. They are making them as cheap as they possibly can, and scrounging around for any big sounding spec they can find to put in big type on the front. Those tiny compressors are designed to be good gifts, not to be good inflators. Throw it out. Buy one of those spray can style one time tire inflators (they just take about 30 seconds) and then drive home to where you keep your really nice shop compressor (or to the gas station) and finish the job properly. And while you're out getting the fix a flat can, stop off and get a new set of tires that don't leak so much.-- oxen crossing, Jun 21 2004 Use a foot-pump. Inflate tyre moderately quickly *and* keep warm.-- benjamin, Jun 21 2004 I feel kind of perplexed to find out that the halfbakery has a 'halfbakery: category' category for non-inventions. What exactly does that mean to a site mostly devoted to inventions?
Is there a 'halfbakery: non-category: invention' category?-- RayfordSteele, Jun 21 2004 [rayford] By looking at the other entries in this category. It seems as though this is a category for the creation of new categories which have other material rather than inventions. This would probably be better suited to a different category (like car:tire), rather than one about the creation of categories.-- reap, Jun 21 2004 See [linky] for the fastest method.-- Custardguts, Nov 22 2007 random, halfbakery