BD
02-06-2019, 09:07 PM
I need a new keyed chuck for a drill press, and I really don't know enough about this to make an intelligent decision.
Short version: I needed a drill press on a job site that's local to wear I live so I got a couple of carpenters to help move the 3/4hp 14" Rockwell press from my shop to the site. The guy on one end snagged his pocket on the peg chains on my tractor and dropped the head of the press on the floor, busting up the belt cover and bending the motor shaft. I was able to replace that stuff, but in the meantime I bought another, larger, used drill press to do the work at the site. The replacement is a Craftsmen 2hp 20" press which has some features that are a big improvement over the smaller Rockwell for most of what I do. Unfortunately the chuck on the Craftsmen is loose as a goose. I put an indicator on the arbor and the runout is around 1 thousandth, (about the same as the Rockwell), but a bit in the chuck runs out more like 20 thou, and while it's tight in the jaws, the bit and jaws are loose in the chuck housing. OK for what we're doing at work right now, but I wouldn't want to try drilling and tapping scope mounts with it. The chuck is bigger than I need, 3/16" to 3/4" marked RJ4-19L. The parts list for this press lists the arbor as an MT3 JT4. When I bought the used Rockwell in 1995 for $100 I paid $150 for a good Jacobs chuck and twenty years later the runout on a bit is still not measurably greater than the runout on the arbor. However, these days the equivalent Jacobs chuck for the larger press is nearly $600 new. On line I see many options, some under $50. I really don't need 3/4", I think a 1/32 to 5/8 would suit me better, but a good Jacobs in 5/8" is still over $500. Are any of the other brands out there worth considering? Am I correct in assuming that any MT3 taper for the press quill will work as long as the chuck end matches the chuck spec? How much am I really giving up by giving up bearings in the chuck? Any brand names you'd recommend less expensive than the Jacobs?
Short version: I needed a drill press on a job site that's local to wear I live so I got a couple of carpenters to help move the 3/4hp 14" Rockwell press from my shop to the site. The guy on one end snagged his pocket on the peg chains on my tractor and dropped the head of the press on the floor, busting up the belt cover and bending the motor shaft. I was able to replace that stuff, but in the meantime I bought another, larger, used drill press to do the work at the site. The replacement is a Craftsmen 2hp 20" press which has some features that are a big improvement over the smaller Rockwell for most of what I do. Unfortunately the chuck on the Craftsmen is loose as a goose. I put an indicator on the arbor and the runout is around 1 thousandth, (about the same as the Rockwell), but a bit in the chuck runs out more like 20 thou, and while it's tight in the jaws, the bit and jaws are loose in the chuck housing. OK for what we're doing at work right now, but I wouldn't want to try drilling and tapping scope mounts with it. The chuck is bigger than I need, 3/16" to 3/4" marked RJ4-19L. The parts list for this press lists the arbor as an MT3 JT4. When I bought the used Rockwell in 1995 for $100 I paid $150 for a good Jacobs chuck and twenty years later the runout on a bit is still not measurably greater than the runout on the arbor. However, these days the equivalent Jacobs chuck for the larger press is nearly $600 new. On line I see many options, some under $50. I really don't need 3/4", I think a 1/32 to 5/8 would suit me better, but a good Jacobs in 5/8" is still over $500. Are any of the other brands out there worth considering? Am I correct in assuming that any MT3 taper for the press quill will work as long as the chuck end matches the chuck spec? How much am I really giving up by giving up bearings in the chuck? Any brand names you'd recommend less expensive than the Jacobs?