From: John De Armond
Subject: Re: Where are you getting your air?
Date: Tue, 27 Mar 2007 20:24:39 -0400
On Tue, 27 Mar 2007 13:25:51 -0400, bill horne <firstname.lastname@example.org>
>> Excellent point - gauges vary a lot. It's really ridiculous to
>> agonize over minuscule pressure changes due to shade, etc when your
>> gauge may be off 20%!
>I just gathered up all my 97 cent WalMart pencil-type gauges - 5 of
>them - and checked them. 4 of them read within 1/2 lb of each other,
>and one was different by 1 1/2 lbs. Assuming that the 4 were not all
>wrong by a significant amount - and since my tires wear normally, I
>think that's a reasonable assumption - that means the worst was off
My experience is the same, Bill. Back in my racing days where I
really worried about tire pressures, I spent a small fortune trying to
find something more accurate and more rugged than the humble tire
gauge. Turns out those spring-piston tire gauges are quite accurate,
usually to +- 1 minor graduation. And they can take a beating.
At each of my old trucking company's garage depots there was a tire
gauge checking station. A pressure regulator, a 1% precision gauge
and a shraeder valve. The sign encouraged checking gauges whenever
one was in the garage. It also said that inaccurate gauges (off by
more than 1psi) would be replaced free (we had to buy our gauges,
cheap pricks that they were!) One time I asked the counter guy how
many inaccurate gauges they'd replaced. he replied that other than
those that had been run over or used for pry bars, none.