JasonPAtkins
Hot Rolled
- Joined
- Sep 30, 2010
- Location
- Guinea-Bissau, West Africa
Hi all, I've been away for a while, but get to get back to work soon!
I work at a fab school in West Africa and get to send a limited amount of stuff in a shipping container headed out soon. One of the things on my wish list for some time is a stout ring roller. It's main uses would be 2"x1/4" bar the hard way, angle, mostly leg in, up to at least 1-1/2"x3/16", and some solid rounds up to 3/4". I'd like to design it to be able to get close to 1-3/4" OD 1/4" wall pipe if needed as well.
The plan would be to build it from scratch, and I've spent a fair amount of time collecting build threads around different sites to come up with a final drawing. I don't have the final drawing yet, but have just this weekend to carefully choose from my stock shelves here in Michigan what to send over.
There were a few threads a while back on PM debating what kind of bearings to use for such a project, and I realize the answer to that will affect the diameters of the tube. I'd like to build one like the industrial models, with the rolls on the outer side of the two vertical pieces of plate, not one of the horrible freight type models where the rolls are in between the two plates.
I can scavenge the solid round from the scrap yards over in Africa, so I'm not worrying about that part now.
Here's what I know:
1) I have a 13" long piece of 4.5" dia solid 4140 that I assume must be heat treated, because it has black mill scale on the outside. I'm hoping that will be enough material (and hard enough) to make the adjustable width rolls and spacers that come standard on most of these machines, where you can vary the gap to roll bar either way, solid square, angle, and solid round in a pinch.
2) The actual shafting will be scavenged over there
3) I have two pieces of 1/2" wall tube that are candidates for the three tubes that hold the bearings/shafts. One of them is 29" long and 3.5"OD x 2.5"ID. The other is 4.25" OD and 3.25"ID, but is only 19" long. Bigger is probably better, especially if using something other than bronze plain bearings, but I don't know that a third of 19" = 6.333" is long enough for this kind of machine's width.
4) I have a 1/2 hp motor on a 60:1 worm gear reduction to power it. I assume that should be plenty of torque through a big sprocketed drive system, even if it's a little slow. The motor will be on a VFD, so I can overspeed it some.
I need to get the heavy parts over now, but can have someone hand carry the lighter stuff later, like bearings or bronze to make bearings from.
So, here are my specific questions:
A) Am I an idiot. I'm not a super fast machinist and all work will be done on decent manual machines. Does this sound like a 20 hour project or a 200 hour project?
B) If no on A, is 4.5" rough OD enough for the rolls? Bonus points if I can find out the ID of rolls from an established mfg so later I could buy their tooling to use on my machine.
C) Do I go for the 2.5"ID tube where the three sections could be up to 9" long, or the 3.25"ID tube where each can only be a hair over 6" long?
I have seen these machines work on youtube, but never been around one in real life. I would like to try the build, even if I end up making a machine that has less capacity than I was hoping for, my fab students will still get a lot of use out of it.
Advice is appreciated!
I work at a fab school in West Africa and get to send a limited amount of stuff in a shipping container headed out soon. One of the things on my wish list for some time is a stout ring roller. It's main uses would be 2"x1/4" bar the hard way, angle, mostly leg in, up to at least 1-1/2"x3/16", and some solid rounds up to 3/4". I'd like to design it to be able to get close to 1-3/4" OD 1/4" wall pipe if needed as well.
The plan would be to build it from scratch, and I've spent a fair amount of time collecting build threads around different sites to come up with a final drawing. I don't have the final drawing yet, but have just this weekend to carefully choose from my stock shelves here in Michigan what to send over.
There were a few threads a while back on PM debating what kind of bearings to use for such a project, and I realize the answer to that will affect the diameters of the tube. I'd like to build one like the industrial models, with the rolls on the outer side of the two vertical pieces of plate, not one of the horrible freight type models where the rolls are in between the two plates.
I can scavenge the solid round from the scrap yards over in Africa, so I'm not worrying about that part now.
Here's what I know:
1) I have a 13" long piece of 4.5" dia solid 4140 that I assume must be heat treated, because it has black mill scale on the outside. I'm hoping that will be enough material (and hard enough) to make the adjustable width rolls and spacers that come standard on most of these machines, where you can vary the gap to roll bar either way, solid square, angle, and solid round in a pinch.
2) The actual shafting will be scavenged over there
3) I have two pieces of 1/2" wall tube that are candidates for the three tubes that hold the bearings/shafts. One of them is 29" long and 3.5"OD x 2.5"ID. The other is 4.25" OD and 3.25"ID, but is only 19" long. Bigger is probably better, especially if using something other than bronze plain bearings, but I don't know that a third of 19" = 6.333" is long enough for this kind of machine's width.
4) I have a 1/2 hp motor on a 60:1 worm gear reduction to power it. I assume that should be plenty of torque through a big sprocketed drive system, even if it's a little slow. The motor will be on a VFD, so I can overspeed it some.
I need to get the heavy parts over now, but can have someone hand carry the lighter stuff later, like bearings or bronze to make bearings from.
So, here are my specific questions:
A) Am I an idiot. I'm not a super fast machinist and all work will be done on decent manual machines. Does this sound like a 20 hour project or a 200 hour project?
B) If no on A, is 4.5" rough OD enough for the rolls? Bonus points if I can find out the ID of rolls from an established mfg so later I could buy their tooling to use on my machine.
C) Do I go for the 2.5"ID tube where the three sections could be up to 9" long, or the 3.25"ID tube where each can only be a hair over 6" long?
I have seen these machines work on youtube, but never been around one in real life. I would like to try the build, even if I end up making a machine that has less capacity than I was hoping for, my fab students will still get a lot of use out of it.
Advice is appreciated!