Mumbles Posted June 8, 2010 Posted June 8, 2010 I'm looking to make some hummers for the next shoot, and perhaps some competition entries. Does anyone have any hints or tips? Right now I am planning to use .5" ID x 1" long parallel wound tubes (1/8" walls), with probably a 1/8" or 3/32" vent. I am planning to use meal with 7% titanium. My meal is generally pretty hot, equaling if not surpassing commercial BP in lift. I blew up several farfalle inserts with the same mix. Do you guys think I should tone down the meal with maybe 5-10% charcoal?
sparksnsky Posted June 8, 2010 Posted June 8, 2010 I'm looking to make some hummers for the next shoot, and perhaps some competition entries. Does anyone have any hints or tips? Right now I am planning to use .5" ID x 1" long parallel wound tubes (1/8" walls), with probably a 1/8" or 3/32" vent. I am planning to use meal with 7% titanium. My meal is generally pretty hot, equaling if not surpassing commercial BP in lift. I blew up several farfalle inserts with the same mix. Do you guys think I should tone down the meal with maybe 5-10% charcoal? I'd say its a matter of pressure. If you use a press and a sleeve for the paper tube, then force will consolidate your mix so much that it cannot blow up. I've made hummers with such hot BP and dimensions you say but without Ti using a press and the hum produced was loud. I think that if you add more charcoal there is a possibility to loose the hum, because thrust is moderated then.
PyroMan LTU Posted June 8, 2010 Posted June 8, 2010 I made hummers some time ago. i used also .5" ID tubes around inch long. My BP isn't so tough maybe but I used shimizu's composition: Meal - 70BP granules (20-40mesh I used) - 10Al (I used very fine and dence aluminium it is said to be 7um) - 20 This composition worked fine, just It didn't produce as good sparks as Ti would. Ti here where I live is very expencive, for me at least And about you're mixture - I'd make a few tests If I were you It's the best way to find out, I think. No one know's how strong your meal is PyroMan
TheEskimo Posted June 8, 2010 Posted June 8, 2010 (edited) I use that finer mesh spherical Ti that Skylighter no longer carries. I so totally should have ordered more than one pound:(. I am rationing it like it's gold.I use regular 75-15-10, lightly milled so that it burns quickly, but not like meal. Fast 60-30-10 also works well. Add the usual amount of Ti. I then granulate this with acetone or water. As a note, the BP doesn't have to be the fastest to get them to work. The angle of the hole into the tube always matters.Anyways, I have used the 1pound tubes from Skylighter for them. I cut them about 1.5-2 inches long. I pound in about .25-.35 inches of clay. I then drill in, with a 1/8 in drill bit, at an angle into the tube, just level with the clay. I insert a fuse, and and ram in enough fuel to leave room for a bulkhead at the other end. I then ram in a clay bulkhead.2 vids for your enjoyment, both made using said methods.http://www.youtube.c...h?v=mBOFL0_aoXk Edited June 8, 2010 by TheEskimo
PyroMan LTU Posted June 9, 2010 Posted June 9, 2010 Eskimo, that sound more like shimizu describes as "mad lion" Nice!
Recommended Posts