Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 73 users online :: 3 registered, 0 hidden and 70 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

Registered users: Bing [Bot], Google [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

Need Answer ASAP

Post questions and info about hybrid (compressed gas with fuel) powered cannons here. This includes discussion about fuels, ratios, ignition systems, build types, safety, and anything else relevant.
Sponsored 
  • Author
    Message

Need Answer ASAP

Unread postAuthor: FishBoy » Thu Dec 04, 2008 7:31 pm

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)
  • 0

"You polish a turd, it's still a turd"

Remember DYI!!!
User avatar
FishBoy
Colonel
Colonel
 
Posts: 575
Joined: Tue May 27, 2008 5:51 am
Reputation: 0

Unread postAuthor: mark.f » Thu Dec 04, 2008 7:43 pm

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?
  • 0

User avatar
mark.f
Donating Member
Donating Member
 
Posts: 3464
Joined: Sat May 06, 2006 11:18 am
Country: United States (us)
Reputation: 21

Unread postAuthor: FishBoy » Thu Dec 04, 2008 7:54 pm

uuuuuhhhh... heh heh

(i got the volumetric, what's mano again?)
  • 0

"You polish a turd, it's still a turd"

Remember DYI!!!
User avatar
FishBoy
Colonel
Colonel
 
Posts: 575
Joined: Tue May 27, 2008 5:51 am
Reputation: 0

Unread postAuthor: Fnord » Thu Dec 04, 2008 8:00 pm

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".
  • 0

Image
User avatar
Fnord
Major General
Major General
 
Posts: 2244
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Reputation: 7

Unread postAuthor: starman » Thu Dec 04, 2008 8:39 pm

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
  • 0

User avatar
starman
Donating Moderator
Donating Moderator
 
Posts: 3041
Joined: Wed Dec 12, 2007 12:45 am
Location: Simpsonville, SC
Reputation: 0

Unread postAuthor: psycix » Fri Dec 05, 2008 4:07 am

A manometric meter is only useful if you have a very accurate gauge and run on a high mix.
Most launchers simply use volumetric.
  • 0

Till the day I'm dieing, I'll keep them spuddies flying, 'cause I can!

Spudfiles steam group, join!
User avatar
psycix
Donating Member
Donating Member
 
Posts: 3684
Joined: Mon Jun 25, 2007 7:12 am
Location: The Netherlands
Reputation: 0

Unread postAuthor: starman » Fri Dec 05, 2008 8:44 am

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.
  • 0

User avatar
starman
Donating Moderator
Donating Moderator
 
Posts: 3041
Joined: Wed Dec 12, 2007 12:45 am
Location: Simpsonville, SC
Reputation: 0

Sponsored

Sponsor
 


Unread postAuthor: Larda » Fri Dec 05, 2008 9:03 pm

I can tell you that DYI is in good health. :)
  • 0

Push to test... Release to detonate.
User avatar
Larda
Donating Member
Donating Member
 
Posts: 119
Joined: Wed Jul 18, 2007 7:52 am
Location: Sweden
Reputation: 0

Return to Hybrid Cannon Discussion

Who is online

Registered users: Bing [Bot], Google [Bot], Yahoo [Bot]

Reputation System ©'