Quote:
Originally Posted by Stan Hoover
Edgar,
Can you share what speeds you would recommend??
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Stan, Given that the old hand crank tools were in use for paper hulls, I run my Rockwell press at 300 rpm. I'm using Nick Ross tools which have more pins than the common ones sold by either BP or precision.
The key to roll crimping plastic hulls is A) start with a smooth case mouth. If you're roll crimping 2 3/4" hulls, you already have enough extra to trim off, because the roll uses less than the star crimp. B) Heat. Start with a light pressure on the hull and withing a few seconds you'll feel it begin to roll, because the plastic is more pliable when warmed up by friction. Once its begining to roll, give it more pressure, and don't delay, because you can soften the plastic too much, and get crappy results.
I roll my 8ga hulls at a much slower speed, because the tool has six pins. I do them in either my Bridgeport with the back gears engaged.(I'm not suggesting you go out and buy a 2000lb milling machine) Anything more than 150-200 rpm and the tool heats up and scars the outside diameter of the hull.
Be aware of the tool temperature. I load up a tray with 25 or 50 hulls at a time, but don't roll all at one shot because the tool gets too hot. Rolling paper (I roll 12,16 & 20 paper also) heat doesn't seem to hurt the hulls but paper likes the slowest speed, or it scars, almost tears, the lip.
I've had many conversations with Nick Ross, and I will say, he puts a great deal of thought into his tools. To the extent, he is considering two different tools for 8 ga. hulls because of the hull thickness difference between Winchester and Remington industrial hulls. The 'smoothness' of the inside diameter of the finished roll is as important as the outside, and the internal tool profile takes hull thickness into account.
Cheddite paper hulls are thinner than Federals, and roll well with Ross tools, but I roll the Federal hulls in and old Deluxe Bridgeport Implement Co hand cranked roller.