# Chuck and bearings runout question



## astjp2 (Jun 4, 2019)

So I picked up a Duracraft DP1214 drill press for cheap.  It has a 5/8" MT2 chuck, so I bought a couple of MT2 threaded adapters for some smallerjacobs chucks that I have.  Right now the run out is between .0025- .003"  Would this be acceptable for all 3 chucks?  It also has a growl, I am thinking that either a belt or bearing is bad, is it worth tearing down to put new bearings and belts on or should I just run it to failure?  Tim


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## mikey (Jun 4, 2019)

When you say you have 0.0025 - 0.003" TIR, how and where are you measuring this? I ask because dynamic run out that is checked while the machine is running is fraught with inaccuracy and tells almost nothing about what is doing what. 

It sounds like this machine has an MT2 socket and it might be a good idea to check static concentricity inside the spindle to see what that looks like; this will give you a baseline so you'll at least know what the spindle is doing. If you then install a chuck and have a large increase in static run out then you know that it is the arbor, the chuck or the way the arbor was install in the chuck. 

I don't know anything about Duracraft machines but from a quick search on the net, it is a Taiwanese machine. Typically, these machines were made to a price point and it is a good bet they use cheap shielded bearings on the spindle and drive sleeve. When these bearings go bad you will see run out increase and hear excessive noise when it runs. They will also run hot. If you wish to get it running as accurately as you can, change both the spindle and drive sleeve bearings with good sealed bearings. This makes a huge difference in accuracy.

Drill presses are not intended to be precision machines, just as drills are not precision cutting tools. However, I can tell you that 0.003" TIR at the arbor is enough to see 0.006" TIR at the end of a drill and that much run out is visible as a wobble. If you see that, its time to assess the machine.


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## astjp2 (Jun 5, 2019)

I put a TDI inside the spindle and it was the same as when I put in a dowel pin in the chuck.  It looked to me that the arbor was running true in the spindle but the spindle was not running true.  I guess I will pull the spindle bearings and get some replacement belts from Motion.  It is a way heavier machine than what I had before.  I guess I will have to mill a socket to make a spanner socket to get the spindle nut off.  

I need to get my Delta DP220 cleaned up and rebuilt too.  That one needs the chuck fixed and new bearings, I can turn the spindle on it and feel the grit in the bearings.


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## mikey (Jun 5, 2019)

If you replace the spindle bearings, replace the drive sleeve bearings at the same time. If one pair is shot it's a good bet that the other pair have failed as well. Both contribute to run out. Good luck!


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## astjp2 (Jun 5, 2019)

mikey said:


> If you replace the spindle bearings, replace the drive sleeve bearings at the same time. If one pair is shot it's a good bet that the other pair have failed as well. Both contribute to run out. Good luck!


drive sleeve?


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## mikey (Jun 5, 2019)

The spindle rotates inside two bearings at either end of the quill; these are the quill bearings and there are two. The spindle extends up through a sleeve with internal teeth that match those at the top of the spindle. This is the drive sleeve that runs inside two more bearings separated by a spacer. The top of the sleeve has a taper that mounts the drive pulley. As the pulley turns, it turns the drive sleeve that, in turn, drives the spindle. That is how power is transmitted to the chuck.

When you change bearings, you should change all four - two quill bearings and two drive sleeve bearings. Pull the bearings and buy the equivalent bearings but I suggest you use sealed bearings, not shielded ones. The grease in sealed bearings last longer. I also suggest you buy deep groove bearings from Nachi or NSK. Deep groove bearings can sustain high axial and radial loads and quality Japanese bearings are worth the small extra cost. 

My 30 year old Craftsman drill press has Nachi bearings that are at least 8 - 10 years old by now and it still holds about 0.0005" TIR at the spindle despite frequent use. Most folks worry about how accurate their drill chucks are but the primary source of accuracy in a drill press are in the bearings, all four of them.


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## markba633csi (Jun 5, 2019)

Sealed bearings have the rubber seals, shielded ones have a thin metal cover with a tiny gap that can let debris in.  Nachi makes good, reasonably priced bearings, it's a Japanese company.  
Mark


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## astjp2 (Jun 6, 2019)

So I got the drill press apart, it is missing a few small items like thumb screws but it is intact.  
I pulled the spindle, it has a 6205 and a 6203 bearings in it,  the grease was old and stiff but not gritty.  With the spindle in the vise, runout was .0002

There was an intermediate slow speed pulley that seems to be causing most of my problems, there seems to be a manufactures defect in one of the sheaves, and the 6202 bearings were gritty.  It also has belts that were too tight and cracked.  So the only thing I have to do yet for tear down is to get drive sleeve off once I find a spanner socket.  I dont like using a punch to take them off if I dont have to, it makes it hard to get the proper torque on bearings.  

Tim


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## astjp2 (Jun 6, 2019)

mikey said:


> The spindle rotates inside two bearings at either end of the quill; these are the quill bearings and there are two. The spindle extends up through a sleeve with internal teeth that match those at the top of the spindle. This is the drive sleeve that runs inside two more bearings separated by a spacer. The top of the sleeve has a taper that mounts the drive pulley. As the pulley turns, it turns the drive sleeve that, in turn, drives the spindle. That is how power is transmitted to the chuck.
> 
> When you change bearings, you should change all four - two quill bearings and two drive sleeve bearings. Pull the bearings and buy the equivalent bearings but I suggest you use sealed bearings, not shielded ones. The grease in sealed bearings last longer. I also suggest you buy deep groove bearings from Nachi or NSK. Deep groove bearings can sustain high axial and radial loads and quality Japanese bearings are worth the small extra cost.
> 
> My 30 year old Craftsman drill press has Nachi bearings that are at least 8 - 10 years old by now and it still holds about 0.0005" TIR at the spindle despite frequent use. Most folks worry about how accurate their drill chucks are but the primary source of accuracy in a drill press are in the bearings, all four of them.


Mikey, do you happen to know the dash number for the high precision deep groove bearings? I found the  Nachi 6203-2NSE and 6203-2nse9, but I am not seeing in the naichi catalog what the 9 means, they also carry them for the 6205 and the 6202


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## mikey (Jun 6, 2019)

I don't know what the "9" means, sorry. There is a seller from Turkey selling the 6203-2NKE version with free shipping. This is the rubber sealed, non-contact version of your bearing that will take more heat. The 2NSE version is a contact seal type which is fine for a drill press, though.


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## Ulma Doctor (Jun 6, 2019)

The nachi 6203-2NSE9 is the C3 equivalent.
they are suitable for use in electric motors and drill press quills too !

C5 is a higher grade as well as a more expensive bearing

SKF 6203-2RS/C3   are very good bearings too


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## jwmelvin (Jun 7, 2019)

Ulma Doctor said:


> C5 is a higher grade as well as a more expensive bearing



I thought C3 and C5 are increasing clearance, not anything to do with quality. ABEC ratings are the quality rating, right?









						BEARING CLEARANCE | Bearing Corporation
					

BEARING CLEARANCE   Radial Internal Clearance The radial internal clearance of a ball bearing affects life, noise, vibration and heat generation.  It is important to select the appropriate internal clearance for each application. The three types of internal clearance of a ball bearing are radial...



					www.bearingcorporation.com


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## astjp2 (Jun 7, 2019)

Here is a one stop shopping, I was checking ebay but some of those suppliers were 2 weeks to ship, amazon was not any better


			Search Results -> 6205  : CNC Specialty Store, Industrial Supply


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## Ulma Doctor (Jun 7, 2019)

jwmelvin said:


> I thought C3 and C5 are increasing clearance, not anything to do with quality. ABEC ratings are the quality rating, right?
> 
> 
> 
> ...


 my bad, i should have said ABEC5 bearings are more precise and expensive than ABEC3 grade


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## astjp2 (Jun 10, 2019)

what about FAG 7205-B-XL-2RS-TVP?


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## pontiac428 (Jun 10, 2019)

If you want to make it easy on yourself, try vxb.com (vxb bearings) for your Nachi needs.  I've had mixed results buying bearings on eBay, so I prefer to go to a reputable distributor.  The prices are similar to fleabay in spirit, and they won't pass off flood-ruined parts as "new old stock"


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## mikey (Jun 10, 2019)

astjp2 said:


> what about FAG 7205-B-XL-2RS-TVP?



I'm not sure if precision bearings are justified in a drill press, even if they fit. Your call of course. If you can find a double row angular contact bearing to fit in the lower spindle then that would be a win.


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## astjp2 (Jun 12, 2019)

Well I got the pulley off, I found a puller that I forgot I had, now I need to get the shaft out, do I use a piece of all thread and push the shaft out the bottom?


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## mikey (Jun 12, 2019)

It should push out from the bottom. These bearings are usually a slip fit but can bind if cocked in the bore. If you have a small jack, you can put that on the table and put a piece of wood on top of the small jack to push the sleeve out the top.


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## francist (Jun 12, 2019)

Just don't snap the table off in the process


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## astjp2 (Jun 12, 2019)

There is a snapring groove at the bottom of the visible part of the shaft.  I wondering if that is supposed to be used to seat the shaft height.  I am back to the all thread or an acme thread.  I am prone to breaking things with jacks.


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## mikey (Jun 12, 2019)

The circlip below the drive sleeve is just to limit travel of the lower drive sleeve bearing - its just a stop and need not be removed or disturbed. 

The drive sleeve is a SLIP FIT in the bore and does not require a great deal of force to remove it. I suggested a jack to simply give you a controlled way of nudging the sleeve out without cocking it. There is almost no force applied that could damage anything as long as the sleeve comes out straight. You could use a piece of pipe and all-thread to pull the sleeve out if you wish; it will accomplish the same thing.


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## john.k (Jun 13, 2019)

Personally,I would be very happy with 005 runout in one of the Oriental pillar drills.....usually around 015,and the runout is in the spindle .....the cure is to use a oriental chuck ,and before mounting the Jacobs taper permanently ,see if you can equalize the runout..........incidentally,the first time a drillbit slips in the chuck,all bets are off ,and runout will be anything,depending how much damage is done to the jaws.


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## astjp2 (Jun 14, 2019)

I pressed out the spindle bearings and the drive sleeve bearings today, I got a few surprises!  I wound up pulling the head off the column to get the spindle sleeve bearings out, I had to turn the head upside down and use the arbor press to get them out.  They were not just a slip fit.  They also only come out one way!  I also press the spindle bearings out of the quill.  I found a 3rd bearing.  It is an NTN 51105 thrust beairng.  Now I just need to order new 7 bearings and 2 A26 belts and a few hours, I am back in business!  Woo Hoo!


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## astjp2 (Jun 14, 2019)

john.k said:


> Personally,I would be very happy with 005 runout in one of the Oriental pillar drills.....usually around 015,and the runout is in the spindle .....the cure is to use a oriental chuck ,and before mounting the Jacobs taper permanently ,see if you can equalize the runout..........incidentally,the first time a drillbit slips in the chuck,all bets are off ,and runout will be anything,depending how much damage is done to the jaws.


Well I was able to get the spindle bearings cleaned out a little and the spindle runout was less than .001, so a good set of sealed bearings pressed in and I will have a good drill press.  I am worried about  the pulley that has a chunk missing causing a problem, I guess I will find out when I run it.


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## astjp2 (Jun 19, 2019)

I found some
*SKF 6205 RSJEM*

The are listed as ABCDE1 precision bearings.  Prices are better than the Naichi bearings.  What sayeth the tribe?


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## mikey (Jun 19, 2019)

SKF makes good stuff. If it fits the machine and budget, go for it.


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## astjp2 (Jun 19, 2019)

Bearings were $68 for all 5, I got 3 of the SKF 2RS-jem bearings for the spindle and 2 Naichi bearings for the drive sleeve.


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## astjp2 (Jun 25, 2019)

bearings are installed, the drive sleeve has a tight spot in it when I rotate it, the spindle now has .0004.  I need to get one more belt, Oreilly's carries gates A22 and a26 belts for under $10 each.  I dropped the metric set screw that holds the collar on the spindle splines, so I have to go get one of those soon.  I also need to replace a few handles, I found what I think I need from https://www.essentracomponents.com/en-us/knobs-handles-grips/levers/gear-lever-assemblies-shafts  They also carry machine handles for decent prices.  I ordered from them before and was satisfied.  Tim


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## mikey (Jun 25, 2019)

Tim, have you sorted out why there is a tight spot when you rotate the drive sleeve? That should not be there. Is the spindle straight?


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## astjp2 (Jun 26, 2019)

No, I pressed them onto the shaft and they felt like it had a stiff spot once I pushed them into the head, so I am going to run the press without the spindle and see what happens.  I don't have any gritty feeling from the balls brinelling into their races, I am thinking that one of the bearings is bad.  The spindle is still removed.


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## mikey (Jun 26, 2019)

Haven't ever seen a bad Nachi bearing out of the box but I guess that can happen. Keep us posted, please.


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## astjp2 (Jul 2, 2019)

Well I ran the drill press tonight after putting the pulleys and spindle back in.  So after about 20 minutes of free wheeling, I checked the bearings, the press started to clatter a little so I checked the spindle first.  Those bearings were cool.  So next was the drive sleeve, well they were pretty hot.  It was about a 4 seconds and pull your had off.  The slow speed pulley, now that was a different story.  It was so hot I was expecting to see smoke.  

Now I know that the belts were a little loose and may have contributed a little towards the heat but I really think it was not that big of a factor since the motor pulley was only warm.  So I have to get an a25 belt for the spindle side and I have a new 4l240 for the motor side.  If the belt changes dont cool down the pulleys, I will pull the bearings in the slow speed pulley and see if I did something wrong. If not, I will order another pair, its not like they are expensive.  

So I checked the runout at the MT adapter, it was showing about <.0015 tir, but putting in a precision pin into the screw on Jacobs chuck gives me about .010, so I swapped chucks, it went down to about .006, so I swapped adapters and it was similar.  I have another MT to JT3 adapter, I will put a pin in on it an see what I get with it.  My first priority should be getting the correct belts and my heat issue under control.  Well at least I am learning with this project.  

I used a gray moly lube on the spindle sleeve to spline, white lithium for the 51105 bearings.  I would have prefered using red lithium but in this application it should be fine for the next 40 years.  

That is all for now.  I just want a descent heavy duty drill press, this should work ok once I get it squared away.  Tim


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## astjp2 (Jul 7, 2019)

Well I did some troubleshooting on the heat issue, I checked the alignment of the pulleys, they were off by about 3/16" total between the three.  I also pulled the hat plate from the motor that mounts the motor to the adjuster.  So my heat problem got better, the intermediate pulley still gets hotter than I want to touch but the other 2 pulleys are just over warm.  Now I have a vibration with the motor, but a little block of wood keeps it from vibrating.  Progress!


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