I have around 8 various chucks in the shop with different mileage. Taiwanese Vertex, Jacobs, old Rohm, and other Chinese versions.
My best is keyless VERTEX capable to take 11/16 stock. Measuring run out of a ½” solid carbide LMT ONSRUD (mill with basically zero run out) and measure about 1” below the jaws of the chuck, I get 0.002 run out. Not bad.
One problem with this chuck is, it is unable to take small drill bit. Less then 1/8”
Old Rohm is out 0.005 measured within same location.
Worst is a Chinese junk at 0.015 sitting at the edge of the rubbish bin.
Since it made me sick to watch a small drill wobble (stubby machines drill is not so bad)
with my second best 0.005, I decided to go all out and spent $220 to purchase a brand new Rohm from MSC. As even the Jacobs are now made in China. Read a 4 star review where it stated run out was basically immeasurable.
Today I installed the new chuck to my milling machine.
67437657 CAP. 1/32-1/2 J3 MOUNT ROHM DRILL CHUCK KEY TYPE
Spindle run out is 0.0001 to 0.0002
R8 arbor JT3 run out 0.0004
Top of the drill chuck 0.0005
Body of drill chuck just below the chuck key holes 0.0008
½” carbide stock known to be basically perfect, ½” below jaws 0.0012”.
I thought if it was 0.0005” I would be OK with that. Being a German precision tool,
purchased from reputable supplier, is this acceptable? Only thing I can see is R8 arbor JT3 run out 0.0004”. When measured 2.5 inches lower, that may be the culprit. Maybe new arbor is in order.
My best is keyless VERTEX capable to take 11/16 stock. Measuring run out of a ½” solid carbide LMT ONSRUD (mill with basically zero run out) and measure about 1” below the jaws of the chuck, I get 0.002 run out. Not bad.
One problem with this chuck is, it is unable to take small drill bit. Less then 1/8”
Old Rohm is out 0.005 measured within same location.
Worst is a Chinese junk at 0.015 sitting at the edge of the rubbish bin.
Since it made me sick to watch a small drill wobble (stubby machines drill is not so bad)
with my second best 0.005, I decided to go all out and spent $220 to purchase a brand new Rohm from MSC. As even the Jacobs are now made in China. Read a 4 star review where it stated run out was basically immeasurable.
Today I installed the new chuck to my milling machine.
67437657 CAP. 1/32-1/2 J3 MOUNT ROHM DRILL CHUCK KEY TYPE
Spindle run out is 0.0001 to 0.0002
R8 arbor JT3 run out 0.0004
Top of the drill chuck 0.0005
Body of drill chuck just below the chuck key holes 0.0008
½” carbide stock known to be basically perfect, ½” below jaws 0.0012”.
I thought if it was 0.0005” I would be OK with that. Being a German precision tool,
purchased from reputable supplier, is this acceptable? Only thing I can see is R8 arbor JT3 run out 0.0004”. When measured 2.5 inches lower, that may be the culprit. Maybe new arbor is in order.