hondo Posted November 6, 2007 Share Posted November 6, 2007 I fixed my bottle jack and attached a pressure gauge, I also signed up for pass fire, in the rocket section there is a calculator for detrrmining pressure, when I calculate it I come up with about 3500 psi, on the site it comes up to 1918 psi, I am making 1 pounders, 0.750 Id, my press ram is 1.375 and the rammer is 0.747. I tried to press on last night and can get to 3500 with out cracking the casing, is the calculation on passfire the right pressure? Link to comment Share on other sites More sharing options...
Mumbles Posted November 6, 2007 Share Posted November 6, 2007 Where are you getting the force measurement? Are you just using the maximum your press can produce, or do you have a gauge of some sort? Link to comment Share on other sites More sharing options...
hondo Posted November 6, 2007 Author Share Posted November 6, 2007 Yes I have a pressre gauge, and that is where I am getting the readings Link to comment Share on other sites More sharing options...
FrankRizzo Posted November 6, 2007 Share Posted November 6, 2007 What's your gauge pressure reading? Link to comment Share on other sites More sharing options...
hondo Posted November 7, 2007 Author Share Posted November 7, 2007 sorry, but read my first post cause I told you that there. The question is if any one has a pressure gauge on their hydrolic press and pressing 1 pound rockets what pressure are you pressing them. If I press at 3500 psi I split the casing on purchased tubes not hand rolled Link to comment Share on other sites More sharing options...
Mumbles Posted November 7, 2007 Share Posted November 7, 2007 In your first post you say when you calculate it, you get 3500. You never state this is a reading in anyway. Anyway, assuming it's the actual pressure being read by the press, you have roughly 11750 psi on the tooling. Even higher if using a cored rammer, such as one used for ramming nozzles. It's really easy if you look at the units. 3500 pounds per square inch. Pounds is the force. So multiply this by the area of your ram, which is 1.4848 sq in. This gives 5196 pounds of force. Divide this by the area of your ram, which is .4382 sq in, and you get your value. Link to comment Share on other sites More sharing options...
NightHawkInLight Posted November 7, 2007 Share Posted November 7, 2007 The first post says it comes to 1918psi on site. I don't know if that was an edit or not. Link to comment Share on other sites More sharing options...
Mumbles Posted November 7, 2007 Share Posted November 7, 2007 I think he means passfire when refering to "the site". Thats the way I read it at least. Link to comment Share on other sites More sharing options...
hondo Posted November 7, 2007 Author Share Posted November 7, 2007 Ok on passfire, in the rocket section there is a fill in the blank formula section for pressing rockets and when I enter the variables the pressure at the gauge says 1918 psi. and in the formula section when I work out the formula and enter the same variables I get a differnt answer( 3500 psi), so am I to assume I calculated it wrong or passfire is wrong, all I know ,I cannot press the black powder fuel to 3500 psi (gauge reading) with out splitting the casings Link to comment Share on other sites More sharing options...
Mumbles Posted November 7, 2007 Share Posted November 7, 2007 I understand what you're saying now. You calculated it wrong, passfire is right. With your setup, the following are your values Gauge Reading - applied pressure1918 - 6500psi3500 - 11750 psi You want 1918 on your gauge for BP rockets. Link to comment Share on other sites More sharing options...
hondo Posted November 8, 2007 Author Share Posted November 8, 2007 thanks thats what I needed to know, now I just need to redo my press for a more stable one. threaded rod streachs too much, Like always I could have purchased a press at harbor freight for the time and cash that I have in the home made one Link to comment Share on other sites More sharing options...
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