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Old Brown and Sharpe Rotary Table Help Please
- Thread starter Janderso
- Start date
Mine is a 6" Chinesium RT with a MT center. I wanted a center hold down & made 1 to fit the MT center that bolts from the bottom, is just lower than the surface of the RT table & is threaded for a hold down. Why not make a plug, dial in center on the outboard of the RT table & then drill & tap a hole in the center of plug?
Here’s a pretty easy expandable plug I made awhile back. Aluminum plug snug fit to hole then sliced and taper put in bottom. Stainless threaded taper gets pulled up into the plug and expands. Use any length bolt to hold your part down. That’s a 5/16-18 bolt for a size reference. Very useful for holding can be inserted in RT already mount and can be removed also without having to unbolt RT.
- Joined
- Mar 26, 2018
- Messages
- 8,397
I just found a 1" thick piece of aluminum about 11" square.
I'll need to figure out a way to bore a center hole (Bridgeport) and mate it to the 1 1/4" RT pilot hole.
Should be a fun project. I assume once I mount the sacrificial plate, I can use a small rounded end mill and make the alignment rings.
This is uncharted waters for me.
I'll need to figure out a way to bore a center hole (Bridgeport) and mate it to the 1 1/4" RT pilot hole.
Should be a fun project. I assume once I mount the sacrificial plate, I can use a small rounded end mill and make the alignment rings.
This is uncharted waters for me.
Real easy. Center your RT to the spindle on mill using your preference. Lock both axis. Then mount you aluminum plate on top a sacrificial piece so you can drill your center hole. Probably want to put your mounting holes for the plate in prior to this suggest a tapered head Allen so it will be flush or recessed from cutting surface. I’d fly cut plate then cut center hole making it as perfect as can be for aligning purposes. You can cut OD and put your alignment rings and fly cut all in one set up. Center hole should be a touch bigger than RT center hole so you can access without interference. A thing I’ve found is the slots in RT are never where I need them so a grid bolt pattern might be more useful for hold downs. Good luck.
