SpudFiles

With a manometric meter, the size of the meter doesn't really matter does it?

(if so my chamber will be approxiamately 12" x 1.5" or 1.25")

thanks

edit- my meter will be made from 1/2" copper & will be about 8" or 9" long (planned)

Well, take a look at the name of what you are building.

A manometric meter.

As opposed to a volumetric meter.

So, what do you think?

uuuuuhhhh... heh heh

(i got the volumetric, what's mano again?)

It's just a fancy way of measuring the chamber pressure very precisely when propane is added. You're basically using your chamber as the "meter volume".

You'll need a pressure gauge with a fairly low and accurate range like as is discussed here. Then pressure your chamber for the desired mix, thusly:

Nx.Propane....Air........Total
1-- 0.616psi 14.7psi 0.616psig
2-- 1.23psi 29.4psi 15.93psig
3-- 1.85psi 44.1psi 31.25psig
4-- 2.46psi 58.8psi 46.56psig
5-- 3.08psi 73.5psi 61.88psig
6-- 3.69psi 88.2psi 77.19psig
7-- 4.31psi 102.9psi 92.51psig
8-- 4.93psi 117.6psi 107.83psig
9-- 5.54psi 132.3psi 123.14psig
10- 6.16psi 147.0psi 138.46psig
11- 6.77psi 161.7psi 153.77psig
12- 7.39psi 176.4psi 169.09psig
13- 8.00psi 191.1psi 184.4psig
14- 8.62psi 205.8psi 199.72psig
15- 9.24psi 220.5psi 215.04psig
16- 9.85psi 235.2psi 230.35psig
17- 10.47psi 249.9psi 245.67psig
18- 11.08psi 264.6psi 260.98psig
19- 11.70psi 279.3psi 276.3psig
20- 12.31psi 294.0psi 291.61psig

A manometric meter is only useful if you have a very accurate gauge and run on a high mix.
Most launchers simply use volumetric.

DYI is a real fan of manometric use on his hybrids. However, volumetric I believe can be just as easy if you get your setup right and meter sized properly for the chamber and mix you want.

Speaking of DYI, has anyone heard from him. He hasn't signed in to Spudfiles in about a month now.

I can tell you that DYI is in good health.