If you have a pressure gauge for 1 athmosphere you can usually open it
up and bend a little piece of metal to zero the pointer at "1" and you
have your vacuum gauge.
(No warranty on accuracy, but i've done it and it seemed fine).
ST
On Sun, Mar 22, 2009 at 8:35 PM, warrenbrayshaw
<
warrenbrayshaw@...> wrote:
> DJ Delorie wrote:
>
>> > Sounds like you need a calibrated hole :)
>>
>> That's why I was looking for my vacuum gauge :)
>>
>
> Teenage vacuum gauges are susceptible to peer pressure and will go missing without explanation.
>
> Should it not return I would make an adapter for the hose with many holes drilled along its length and progressively tape them off until you observe the required push on your stack. If the combined area of all these holes starts out equalling that of the open hose, then the experiment will start at nearly no push.
>
> Additionally the shop vac is then getting the maximum cooling air available.
>
> Looking forward to you entry in the spirals competition.
>
>