|Another machine idea, this one more practical.
||[Oct. 19th, 2011|11:13 pm]
Since there's been no word on the rolling mill from the guy out in LA, I've been thinking about how to make one.|
I have a hydraulic forging press coming in the spring, that would give me the up/down and mechanical advantage needed to squeeze steel, but it will also need to have a rotation.
2" dia rollers are trivial -- I have thicker than that in tool steel in stock, and may even just scavenge the roller-mill setup for the rollers and bearings. It really didn't have enough power, though. The Mcdonald plans suggest a 1-1.5hp motor, significantly more than the 1/4hp motor on the existing mill (assuming it ran at all), and a 30RPM final speed.
It looks to me like if you take a 1 HP 56C-frame 1725 RPM motor and connect it directly to a matching 60-to-1 righ-angle gear reducer and connect that to the lower roller assembly via flexable coupling, you'd have your 30 RPM with a weakest-link of the coupling at 680 in-lbs max load. That's nearly a hundred newton meters, for those who think in metric. Try torqing a bolt down with a torque wrench to see what kind of force that is -- you may need a cheater bar. A quick check of McMaster shows similar inserts with twice or more the rating, so even that's upgradable.
Mount thaht on a baseplate that sockets into the press's die holder, put the other roller on the top part, turn it on, and you have a 30RPM rolling mill with hydrualic gap control. It wouldn't have as much feedback as the leg-operated versions, but it should work.
Let's see, that's ~$400, probably andother 100 for shipping, and if I shop around I can probably knock down quite a bit. Not in this year's budget, maybe next year. Hmm, if we go up a notch in power, 2hp on the motor and gear reducer, stronger coupling, it's about $500 plus shipping. Doable. I'll probably wait until I take delivery ofthe press, so I can see how the dies tie in. And, of course, if a mill became available again I'd just go buy one, but this looks doable.