Drill press thrust bearing seat

[tjwanek]

So I purchased a used Grizzy drill press, a G7948 20". I used a hole saw to put some 2 3/" holes in 1/2" mild steel. It did pretty well but it was obvious that there was significant "wobble" in the chuck. So I grabbed a dial indicator I use for measuring tension on a bandsaw mill and rigged up a semi-solid mount for it (I'm new to this stuff). It showed about a 0.01" TIR. Not great.

I ordered new bearings for the spindle and the driveshaft that is connected to the pulleys above (insert pulley?). When I disassembled it all, this shows what the thrust bearing is resting on.

The bearing seat in the quill is badly off center, with very little lip on one side.

Is this going to cause me issues? I replaced the bearings, put it all back together and now get a TIR of .002-003. The obvious issue was one of the bearings in the insert pulley, which could be felt dragging in certain spots.

But I wonder if this is going to come back to bite me later.

 

[Ulma Doctor]

yes the haunting will return, but it might not be as bad as you may envision.

drilling is not a really a precision sport, you may be just fine with what you got.

 

[Superburban]

If you center punch where you want the hole, even an old clapped out drill press can do good holes.

 

[darkzero]

2-3 thou TIR for a drill press is good. What did you mean by "thrust bearing seat"? I can't think of why a drill press like this would use a thrust bearing for the quill. I just looked at the parts manual & did not see any thrust bearings.

It looks like we are looking at the bottom of the quill at the spindle's morse taper. I was gonna say indicate the taper but you stated 2-3 thou. I can't tell from the pic but is there a chamfer machined on the end of the quill? If yes it could be that the chamfer was just poorly machined off center. If the taper was truly machined way off center like that you would be reading a crazy amount of runout.

Earlier this year I rebuilt a 12" import DP. It had a chamfer on the end of the spindle that looked like it was put on there by hand with a file & the edge was very sharp. I don't have a good pic of before but I remachined that chamfer to make it look better. If it is just the chamfer we are looking at it won't affect functionality.

 

[matthewsx]

So,

First of all Welcome To Hobby Machinist, you will get good answers here from friendly people unlike most of the rest of the internet

You're just up the road from our place in Elk Rapids, I understand your town is truly Beautiful

So now I'm going to give you a warning.

Many have trodden down the path you're starting on and few have returned. The answers you seek can be found here but we will most likely direct you to something like this

Mill Rite Vertical Mill - tools - by owner - sale

Mill rite vertical mill 240v, 3ph, 1hp. Includes collets, end mill holders & rotary phase...

nmi.craigslist.org

Cheers,

John

 

[tjwanek]

2-3 thou TIR for a drill press is good. What did you mean by "thrust bearing seat"? I can't think of why a drill press like this would use a thrust bearing for the quill. I just looked at the parts manual & did not see any thrust bearings.

It looks like we are looking at the bottom of the quill at the spindle's morse taper. I was gonna say indicate the taper but you stated 2-3 thou. I can't tell from the pic but is there a chamfer machined on the end of the quill? If yes it could be that the chamfer was just poorly machined off center. If the taper was truly machined way off center like that you would be reading a crazy amount of runout.

Earlier this year I rebuilt a 12" import DP. It had a chamfer on the end of the spindle that looked like it was put on there by hand with a file & the edge was very sharp. I don't have a good pic of before but I remachined that chamfer to make it look better. If it is just the chamfer we are looking at it won't affect functionality.

What you're looking at is the inside of the quill from the bottom. There is an upper and a lower spindle bearing, and directly above the lower spindle bearing is a thrust bearing that is between the seat you see and the spindle bearing. So you have that seat, then a thrust bearing, then a spindle bearing and then the lower end of the spindle. The upper end of the quill only has the spindle bearing.

 

[tjwanek]

So,

First of all Welcome To Hobby Machinist, you will get good answers here from friendly people unlike most of the rest of the internet

You're just up the road from our place in Elk Rapids, I understand your town is truly Beautiful

So now I'm going to give you a warning.

Many have trodden down the path you're starting on and few have returned. The answers you seek can be found here but we will most likely direct you to something like this

Lead me not into temptation...I can find it on my own.

 

[darkzero]

What you're looking at is the inside of the quill from the bottom. There is an upper and a lower spindle bearing, and directly above the lower spindle bearing is a thrust bearing that is between the seat you see and the spindle bearing. So you have that seat, then a thrust bearing, then a spindle bearing and then the lower end of the spindle. The upper end of the quill only has the spindle bearing.

I see now, thanks for clarifying.

 

[Grandpa's Barn]

Not to insult anyone but were you indicating on the spindle or the chuck.? Taper mounted chucks typically require aligning after installation. There's plenty of tube videos on how to do that. Also a chip or burr in a taper will cause major run out. The Asian manufacturers are mot big on cleaning out chips after machining. I had to replace the chuck on my DP with a quality chuck to get it within acceptable tolerance.
Glad you conquered it, enjoy

Sent from my SM-P550 using Tapatalk

 

[tjwanek]

Not to insult anyone but were you indicating on the spindle or the chuck.? Taper mounted chucks typically require aligning after installation. There's plenty of tube videos on how to do that. Also a chip or burr in a taper will cause major run out. The Asian manufacturers are mot big on cleaning out chips after machining. I had to replace the chuck on my DP with a quality chuck to get it within acceptable tolerance.
Glad you conquered it, enjoy

Sent from my SM-P550 using Tapatalk

I tried indicating on both, but the TIR after the bearing replacement was on the spindle. The taper *seems* clean, but I don't have a reamer to really clean it up. I do plan on getting a better keyless chuck to replace the existing chuck.