oldguy Posted March 8, 2011 Posted March 8, 2011 (edited) Anyone have any idea how, or what kind of tooling it takes to knurl a tube end inward. Like this.......... Edited March 8, 2011 by oldguy
Algenco Posted March 8, 2011 Posted March 8, 2011 looks like an old roll crimp used on shotgun shells. Ballistic products sell them, the crimper is chucked in a drill press and spun http://www.ballisticproducts.com/-Roll-Crimping-Tools-/products/128/
dagabu Posted March 8, 2011 Posted March 8, 2011 There is also a hand version available, here is one on eBay. LINK
oldguy Posted March 8, 2011 Author Posted March 8, 2011 You both are gentlemen & scholars.I have a large stationary variable height & speed drill press. Which would be ideal, if I can find a roll crimper to fit. Off to the ammo cabinet to do some measuring. 12 Gauge measures .72920 Gauge measures .615410 measures .410 The tubes I want to roll crimp are ½ inch (.500). With a .025 wall thickness. So, it appears no standard reloading size will work. Called my gunsmith, he has an old 12 gauge one, he will trade for a fifth of good whiskey.I am up for that trade, then plan to take that the 12 gauge example to a machine shop & have one made to suit my needs.
Mumbles Posted March 8, 2011 Posted March 8, 2011 It would appear those tubes may be a bit thick to properly roll down like the example you have.
daron Posted March 9, 2011 Posted March 9, 2011 does anyone elses eyes light up and get warm fuzzy feeling when ya see a pic of box full tubes:) the mind races with ideas
oldguy Posted March 9, 2011 Author Posted March 9, 2011 (edited) Whats the crimp for? The spiral wound tubes? My adult boys work in the high artic, one in an underground diamond mining operation, the other in oil-gas exploration. They suffer winter temps often in the - 30 F range. Far colder if you factor in wind chill. Often they have trouble thawing, deicing or igniting various things. So, I set out to try to resolve that issue for them, with a special purpose flare/fusee that might help in certain instances. I have spiral, parallel & plastic tubes, half, five eighths, three quarter & 1 inch.. The crimp is functional, to hold the plug in place. These are not rocket tubes (subject to CATO), the intended purpose is special purpose ground flare/fusee tubes. A glued in 3/16ths inch thick hard cardboard, Kraft paper or plastic plug would function as well. But, thats crude. I think I can do better. I am still at the 15 ways this way, another 15 ways that way stage. Remember, this oldguy was a pyro virgin just 2 months ago. So, I set out on this project, a utter complete novice in this arena. First thing, I had to get the comp in the ball park. As a beginner I did not realize a comp burns one way unconfined. And, another way confined in a tube. Nor did I realize a hard bound comp, burns differently than a dry slightly compressed comp. I also faced the conundrum of hot burning, verses a desired burn time. Which is a tough nut to crack. Especially so, if you want a flare/fusee to burn at or above a certain temperature, for a certain time. One conflicts with the other, in that hot comps burn fast. Ones that burn slower do not exceed the temp range I am shooting at. Moreover, I want the flare/fusee to have a fairly large flame envelope, as well as emit large long lasting sparks. So, this has been a real SOB from the start. Thermite like comps suffer from hazmat shipping costs. Plus, are dangerous SOB's, that if used wrong could lead to majorsafety factor issues. There are other variables as well. The flare/fusee requires rugged construction, and must store well over the long term. If I used cardboard tubes. They may be encased in a Mylar metal looking durable waterproof shrink wrap film, before loading. Then plastic capped, to make a waterproof seal on both ends. The purpose being rugged & waterproof. I can dip the tubes in a plasticized parlon like solution to waterproof them. But, that adds another laborious step, I don't want to go through, if possible. The trouble with polypropylene plastic tubes, is the filler in them creates a molten plastic residue. I could overcome that by having some custom tubes extruded with less filler, thus more flammable. But, the cost is very high to do that. Simply because the plastic extruder outfits I have talked with have minimum runs, that exceed my needs 10,000 X. I am also experimenting with differing types of plastic tubes, that may combust at the same rate as the comp, without a molten slag residue. Again, with each small step, I run into another puzzle to overcome. So it's been 3 steps forwards, 2 steps back & try again. But, I am patient & slightly tenacious. So, I will get there sooner or later. Edited March 9, 2011 by oldguy
oldguy Posted March 9, 2011 Author Posted March 9, 2011 28ga .550 Good call. I have two 12 gauges, 1 twenty & one .410.I never thought about a 28ga.
oldguy Posted March 9, 2011 Author Posted March 9, 2011 It would appear those tubes may be a bit thick to properly roll down like the example you have. Tube wall thickness is the same as standard road safety fusee/flares.I cut 1 in half & measured it. Which is very near a shotgun shell wall thickness.So maybe, maybe not, I can only try.
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