Problem with chuck runout

[Andy]

I had exactly the same issue with a Clarke drill press I bought a few years ago. For a long time I struggled with it running off centre and then I bought a second hand Jacobs chuck off ebay. Problem was instantly resolved and I now have a very useable drill press.

Obviously you shouldn't have to invest more money when you have already spend a lot on a new machine, however, for the sake of an extra £20 I now have something that satisfies all my needs.

 

[Fergie 307]

If the arbour appears to run true, but a drill clamped in the chuck doesnt, or whatever the arbour error was it is increased, then the first thing I would check is whether the bore is actually concentric. Certainly dont assume that it is on a new one, especially if its a cheap as chips far eastern job. You really do get what you pay for, so you will rarely go wrong with a Jacobs or similar chuck, but yes they are expensive, because they are properly made.

 

[Fergie 307]

On my Chinese chuck, the outside is way off, looks like I machined it!!

To quote a very famous detective.....When you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth.

Have to say in the OP case where he gets a decent reading off the arbour but then any error is magnified with the chuck in place, the very first thing I would be checking is whether the bore in the chuck is concentric with the body. An error there is by far and away the most likely explanation for the symptoms he has got, nothing improbable about it.

 

[bertterbo]

Hello again, just for clarity sake

I take it the arbor isn't bottoming out in the quill like in the fellas video above.

So you were saying, the position of the arbor in the quill doesn't make difference,
not even with the arbor swapped 180 degrees.
I've got that.

Have you got three arbors or just three chucks?


Is the runout greater if chuck is hand turned in the other direction/reverse, i.e possibly noticeable with even the table raised and rod centered in bore.

And do you notice less runout of that rod if twisted so as to align the chuck jaws in the direction of drilling force.

My video demonstrates this well, and originally I was doing this just incase I felt any burrs.
I think it makes a difference.

Just trying to get some insight, as I've spent a few months working on getting my drill working
and only just got the results I was needing, after quite a few attempts.
So have much interest should you get this sorted.
Might save me needing to purchase a dial indicator and base.

I was going to go down this road once I'd exhausted everything else,
and not really content with the machine yet.

Thanks

Tom

The arbor isn't bottoming out, and yep, 3 arbors and 3 chucks

I think you have shown that the drill is OK, I think it's very good, which is good news.

You have also shown that inexpensive chucks are pretty poor and all three are poor. You need to get a much better quality chuck if you need the precision
Out of interest, I did a check on my lathe with a chinese chuck on an MT2 taper.

At the lathe spindle, 0.0025mm runout.
At the MT2 arbor going in to the chuck, 0.005mm
At the chuck with various bits, 0.1mm.
On a 10cm ground steel bar, measured 23cm from spindle measurement point
Reading 1: 0.24mm, then release bar, rotate and tighten a number of times.
reading 2: 0.34mm
reading 3: 0.18mm
reading 4: 0.24mm

Not as bad as your 1mm, but I suspect that's what you will get with a 'non precision' chuck. Some may be a lot better.
I don't see any spec for accuracy in the Axminster user manual, so you don't know if it's in spec. I suspect it will be within their spec for the spindle.

They do specify the runout for their engineering series

"""The TB-16 bench pillar drill is truly designed for engineering and production use. Very heavily built and manufactured to exceptionally accurate tolerances,.This drill press will stand up to hard work day in day out. The headstock has been machined to precisely match the quill housing, virtually eliminating any spindle run-out, even at full quill extension. The tolerance of the spindle runout (Quill movement) is + 0.01mm. """ I don't see a figure for the runout at the chuck.

NOTE: your spindle is well within tolerance for their Engineering series, so you should be really pleased about that!!


I think the issue is the chucks. You either need to get Axminister to give you a better chuck or buy/borrow one to get the improvement you want.

and as @Chief Sawdust Maker just said, make sure the mating surfaces are clean, page 13 in the manual.

Thanks for taking the time to do those measurements. Interesting results. For reference, the replacement chuck they sent (which is different to the one that comes with the drill press) is this one Axminster Workshop 16mm Keyless Chuck. So not exactly cheap.

Sorry if you have already done this, but have you clocked the outside of the chuck. Seems likely that the taper bore is not centred correctly to the rest of it.

The outside of the chuck on all 3 looks off when running, but I didn't think that mattered? surely only the maching of the arbor mount and jaws section matters?

I've contacted Axminster again to see what they say.

 

[AJB Temple]

I had worn chuck issues on my Fobco. Thread here: Chuck advice please - for Fobco Star

After a couple of false starts with eBay Jacobs chucks, which had stacks of run out, I eventually got a sheffield made new and unused old stock from Fobco | store.lathes.co.uk as originally fitted apparently.

That has run out measured at the end of a Fische quill/chuck checker (basically a short steel smooth rod) of about 2thou at most. This demonstrated that chucks vary a lot. I sold on the original and both Jacobs replacements I tried (if they were genuine) on eBay. Kept the Sheffield one of course.

I would invest in a good quality precision engineering chuck. Good luck.

 

[Sandyn]

Thanks for taking the time to do those measurements. Interesting results. For reference, the replacement chuck they sent (which is different to the one that comes with the drill press) is this one Axminster Workshop 16mm Keyless Chuck. So not exactly cheap.

I agree and understand your dilemma. That chuck should not give the problems you are seeing, but what else can it be? Interestingly, I don't see any figures for runout, so what they describe as high precision is unknown.
I doubt it would cause the problem, but have you tried reseating the arbor in 4 positions inside the taper and doing a sanity check on the runout. There are five interfaces (counting the chuck as three) to the spindle. Make sure inside the taper is really clean. I usually get a lint free rag and soak it in IPA (not beer), then push it up inside the taper and rotate.

Do you know anyone with a good chuck you could borrow to do a comparison?

 

[bertterbo]

I agree and understand your dilemma. That chuck should not give the problems you are seeing, but what else can it be? Interestingly, I don't see any figures for runout, so what they describe as high precision is unknown.
I doubt it would cause the problem, but have you tried reseating the arbor in 4 positions inside the taper and doing a sanity check on the runout. There are five interfaces (counting the chuck as three) to the spindle. Make sure inside the taper is really clean. I usually get a lint free rag and soak it in IPA (not beer), then push it up inside the taper and rotate.

Do you know anyone with a good chuck you could borrow to do a comparison?

Reseating the chuck/arbor doesn't seem to help.

Just had an email reply back from Axminster which I am pretty shocked at...

"The spindle run out tolerance is 0.2mm"

 

[Sandyn]

"The spindle run out tolerance is 0.2mm"

This is something I haven't looked at in detail before, but I think that is probably typical for a 'normal' chuck Here and here are Rhom chucks. Their best one is 0.05mm concentricity and 158 Euros, but some of the 'Supra' chucks are 0.35 and 85 Euros!

 

[bertterbo]

This is something I haven't looked at in detail before, but I think that is probably typical for a 'normal' chuck Here and here are Rhom chucks. Their best one is 0.05mm concentricity and 158 Euros, but some of the 'Supra' chucks are 0.35 and 85 Euros!

Interesting.

Looking at some of the most expensive Rohm chucks (£100 +) on Cromwell state "High concentricity of up to 0.15 mm"

Not entirely sure where they're measuring that though

 

[Sandyn]

Looking at some of the most expensive Rohm chucks (£100 +) on Cromwell state "High concentricity of up to 0.15 mm"

Not entirely sure where they're measuring that though

It's only when you start delving into these type of things you realise how vague some of the specs are. I'm sure some quote the runout at the spindle, others with something in the chuck.

 

[Fergie 307]

Reseating the chuck/arbor doesn't seem to help.

Just had an email reply back from Axminster which I am pretty shocked at...

"The spindle run out tolerance is 0.2mm"

In engineering terms that is a shocking figure. Not surprised at the sad face.

 

[Fergie 307]

Interesting.

Looking at some of the most expensive Rohm chucks (£100 +) on Cromwell state "High concentricity of up to 0.15 mm"

Not entirely sure where they're measuring that though

Jacobs give a maximum TIR of 0.004" for their 13mm capacity K2 keyed chuck, which is a whisker over 0.1mm. This is, as far as they are concerned, a cheapo plain bearing job, about £60. For their high precision chuck the figure is 0.0016, they are a bit more pricey !

 

[redhunter350]

A bit late to the party and haven't read every post but reading Bertterbo's opening posts etc my immediate thought were that the Morse taper in the spindle is at an angle to the spindle axis ? If tis is so the mouth of the taper or the arbor which is ver close shows little runout but when you add the length of the chuck and the drill because of the angle the runout will increase.
One way to check this would be to use a morse taper testing/setting mandrel thus no chuck and you can check with a dial gauge close to the chuck and at the tip of the bar, they should read the same or VERY close.
Regarding inexpensive tooling you pays your money etc etc and can be lucky but more often than not its performance is disappointing !

 

[bertterbo]

A bit late to the party and haven't read every post but reading Bertterbo's opening posts etc my immediate thought were that the Morse taper in the spindle is at an angle to the spindle axis ? If tis is so the mouth of the taper or the arbor which is ver close shows little runout but when you add the length of the chuck and the drill because of the angle the runout will increase.
One way to check this would be to use a morse taper testing/setting mandrel thus no chuck and you can check with a dial gauge close to the chuck and at the tip of the bar, they should read the same or VERY close.
Regarding inexpensive tooling you pays your money etc etc and can be lucky but more often than not its performance is disappointing !

Yes, it would be ideal to have a test bar, but at £50, and something I would only use once, probably not something I'll invest in. This is the sort of scenario when you need to know a mate you borrow this stuff off


https://www.rdgtools.co.uk/cgi-bin/sh000001.pl?WD=test mt3&PN=3MT-TEST-BAR-892793D3.html#SID=543

 

[Fergie 307]

In the above case the end of a rod held in the chuck would describe a circle, increasing in diameter the further away from the spindle you get. This is not what the OP appears to be experiencing. The measurements appear reasonable taken off the arbor, but deteriorate once the chuck is installed, and the measurement is taken off a rod held in the jaws. This suggests that the axis of the arbour bore in the chuck is not concentric with the axis of the jaws. So the rod describes a circle, but its circumference doesnt alter, hopefully that makes sense.

 

[Fergie 307]

Going back over the post, I see one of the things causing confusion was that rotating the drill in the chuck gave different readings. This is most probably simply because the jaw parts are not sufficiently accurately machined for them to always close in exactly the same relative positions, so repeatability is not necessarily great. I suspect you might find you would have the same issue of you simply undid the chuck, removed the drill and then replaced it and re tightened the chuck without turning the drill at all. If you can get hold of a really good chuck the difference in the way it operates, smoothness, precision and so on is very noticeable. Keeping the chuck clean and properly lubricated helps, but a chuck that costs £25 is simply not going to be as good as one that costs ten times that figure. How much you need to spend depends on the level of accuracy you want. But you probably need to budget £60+ for a decent quality 13mm capacity, and several times that if you want a high precision item. A regular plain bearing keyed Jacobs or similar should be perfectly adequate for wood working. Always buy from a reputable company. If you take a chance on somewhere like e bay there are so many counterfeit items that the "Jacobs" chuck you buy may well be a Chinese knock off. You can get bargains in second hand tools, but equally you may find that the reason it's being sold is because it's damaged, doesn't run true or whatever. Unless the seller has made specific claims for its accuracy you wont really have any come back. As you may have gathered by now I am a fan of Jacobs chucks. I have several different types, including the high precision ones. I have also acquired a number of Chinese made chucks, mostly already fitted to machines I have bought. Some are not bad and some have been shockers that have gone straight in the bin. So it really is a case of getting what you pay for. Having said that if I had paid £800 for the drill I would be a bit miffed if they couldn't fit it with a bit better quality chuck than they have.

 

[bertterbo]

As I mentioned in an earlier post, they replaced the chuck with this one Axminster Workshop 16mm Keyless Chuck

But I am still getting the same issues.

Can you post a link to the type of high quality Jacobs chucks you're referring to?

 

[Fergie 307]

As I mentioned in an earlier post, they replaced the chuck with this one Axminster Workshop 16mm Keyless Chuck

But I am still getting the same issues.

Can you post a link to the type of high quality Jacobs chucks you're referring to?

Best bet is to look at the Jacobs web site. There you will find all the information you need concerning the various different types, including detailed specs. They dont sell direct, as far as I know, so you will have to search for the particular one you like to get the best prices. For a 16mm capacity plain bearing keyed chuck you are probably looking at £70ish, a bit more for the keyless type I think. This ought to be fine for woodworking use. Their best high precision one the same size is probably in the £250+ bracket, a bit OTT for what you want !

 

[Sandyn]

It's really difficult to find specs for chucks, but here is one which is fairly good 30u, (0.03mm) but very pricey. They have a selection of other quality as well.
Here is a link to some Jacobs stuff I think 0.04mm TIR

 

[Fergie 307]

Interestingly one of the reviews for the axminster chuck you have claims runout as 0.04mm, although not clear what they are referring to exactly. Axminster dont appear to give figures, or not that I could see. Before you go throwin more money at the problem i would confirm your existing meaasurements. So make sure the arbour and spindle bore are spotlessly clean and install the arbour in the spindle. Mark the realtive positions of arbour and spindle with a sharpie or similar. Use your dti to take a runout figure at the top of the projecting arbour taper, and repeat at the bottom. Make sure your dti is at right angles to the surface being measured. Ideally the figure should be the same for both readings. If there is a big variation then either the bore in the spindle is at an angle or the arbour is not straight. Mark the high spot on the arbour with a sharpie, ie where it is closest to the dti. Now take the arbour out and re install it 180 degrees from the previous position relative to the spindle. Repeat your measurements, and note where the high point is, relative to where it was before. If the readings are the same but the high point has shifted 180 degrees then your arbour is straight, and the error is in the spindle. If the readings have changed appreciably then there is an issue with the arbour. To check the arbour properly you really need to mount it between centres. If you cant do this then roll it on a flat surface. Even very small errors can be quite apparent. Hope this is helpful.