Bearing Click

Hi,

I've been doing a lot of work on my Clarke CL430 lathe recently and noticed when it's idle and I turn it that there is a clicking noise,

i'm sure that no gear train is engaged so it leads me to believe that deep within the gubbins of the headstock the wee little taper roller bearing is at least on it's way out.

Although this doesn't seem to have affected the work produced or any run-out, there are no tapers on turned shafts at least.

I would normally be the first to try and mount the challenge of gutting out the headstock and sourcing a replacement bearing to refit, having rebuilt nearly everything but the headstock, but I saw a video of a guy taking one apart on youtube and it looked very involved?

I only wonder to myself if I should be thinking about doing it in the first place.

If anyone wants to know what lead to this situation I think it might have something to do with me drilling out the motor pulley to a larger size and the inevitable happening of it going slightly out of centre, soooo, that would also be something else to redress.

I don't really push my lathe hard very often but it has done a lot of work.

I'll try to anticipate the "get a new lathe" comments, sorry it's not on the cards, just not an option.

Michael W

Edited By Michael-w on 23/04/2017 19:55:55

Could be a loose key?

> I'll try to anticipate the "get a new lathe" comments, sorry it's not on the cards, just not an option.

I'm sure you're capable of changing the bearing. Just take it a step at a time.

Neil

Don't delve into the headstock bearings. It's pretty rare for a taper roller bearing to wear in such a way it makes a clicking noise, providing they are correctly adjusted for preload.

First thing I would do is take the chuck off and rotate the spindle and see if the noise is gone. It seems quite a few Chinese three jaw chucks develop a rattle or click noise over time due to the scroll plate or one of the chuck key barrels being a loose fit in the chuck body.

Second thing to check is the last thing you worked on, the motor pulley. If it is bored a bit off as you say, could be a belt climbing up the side of the V and snapping back into position with a click. Easy test there is to take the belt off and rotate the headstock spindle. If the noise goes away, its source is the belt/pulleys.

Yeah I definitely wouldn't be doing any damage to it but hopefully I could disassemble the rig if I have to, what I would like to do is take a good look at the gear box just under the headstock section to see if I can take a look at any of the headstock components passing through.

First things first though, i'll remove the chuck and belts and see what difference that makes, the turn pinion in the chuck are a little loose so maybe one is waggling around a tiny bit.

Michael W

Might be bad advice as I haven't heard the click, but how about "if it ain't bust don't fix it"?

I once had a car with a gearbox that suddenly got worryingly noisy in third. A car-wise friend told me to ignore it. Four years later when I scrapped the car due to rust, the gearbox was still OK.

A stethoscope can be very helpful pinning down exactly where a noise is coming from. A length of wooden rod can be used or, even better, you can buy the real thing on ebay.

Dave

If for some reason you do decide to do a strip down, grab your camera/phone what ever, and take plenty of photos, so that when it comes to putting it back together you don't have too many spare parts left over.

Ian S C

If it's any help, when I spin my spindle in neutral I get a lot of rattling, turned out it was the turny bits the chuck key fits into, I wrapped a turn of tape round the chuck and .............total silence.

now I know what it is i can ignore it.

Roy.

.

I replaced my headstock bearings.

In my case it was quite straight forward and was certainly not the dark voodoo art some seem to make out it is. But mine is a small and simple lathe.

Hardest thing was having the balls to get quite enthusiastic with a lump hammer and a block of wood to remove the spindle from the old bearing inners.

Initially the job took about an hour to get the old bearings out and the new ones in. ........... Then came the time consuming bit of pre loading the new bearings. You need patience.! I did it over a couple of evenings of gradually tightening, running for 20 mins and feeling the temp. Then suddenly they 'switch on' as the difference between loose and too tight is small.

Remember it's far easier to tighten a taper bearing on the spindle than it is to loosen it again. Loosening it may require application a hammer tap.

Resist the temptation to cut any metal until you are confident that the adjustment is lets say ..... 'in the zone' as if they are very slack you may give them a good hiding and ruin them from new.

Shop around for bearing prices as they can vary considerably for the same item and maker. - Cheap bearings IMHO are a false economy as are cheap lubricants.

After about a week of use they required a very, very slight tightening again. Presumably after it had warmed and cooled a few times the new bearing cups settled into the headstock casting a smidgen more.

Use common sense, patience, clean everything like a hospital operating room and you will be fine.

Nick

Edited By Nick_G on 24/04/2017 14:50:18

Well I started to dismantle the headstock and this was as far as I got to where the rear taper roller starts, the front one is apparently just a "roller bearing"? according to the diagram.

The rear one seems to be the one clicking, it quietens down if I put a little grease on it. I watched a youtube vid of a guy doing exactly what Nick G, said, luckily the guy specifies the part from RS at £18.

Having said that, it would probably be wise for now to leave everything alone, but I've saved the link to the bearing I need just incase, it's only noticeable very quietly if it's idle and turned by hand, I am going along with S.O.D's wisdom here and, if it's not affecting anything i'm making, it's probably better to leave it for now.

I am glad though that I am atleast aware of what I need to do just incase, I think all that needs to come out after the pulleys is a front securing plate and the whole assembly can be knocked out with a wooden dolly.

Michael W

That's good. No point in fixing a problem that is not a problem.

Have you adjusted the pre-load on the bearings so there is no slack? That might eliminate the rattle.

If you do eventually fit new bearings it is worth paying the extra money for good brand name bearings such as Timken or SKF from a specialist bearing supplier. Unbranded bearings off the net are an unknown quantity of widely varying quality.

I don't know this lathe, does it have back gear, if so is it the (disengaged) pin in the bull gear clicking over the engagement hole in the pulley assembly.

Ian S C

Thanks for the suggestion, but there is no back gear on this one, just a gear box that runs below the headstock for switch between half speed, idle, full speed for the lead screw self cut pitches.

Although sound can be deceiving sometimes, i'm fairly confident this is a little bit of bearing noise, which doesn't seem to be affecting the performance of the machine for the moment so I'll leave it.

You can only notice it if you really listen and it may have been that way since I've had it and just simply didn't notice it before.

Michael W

I don't think i'd even know where to begin on pre-load, I haven't touched the headstock since I bought it. All I've seen from the utube vid is that it's a taper roller that sits inside a tapered ring, which is just force fitted into the housing.

I think you're probably right about the bearings too, but i reckon RS is pretty sound when it comes to their selection.

Michael W

.

At £18 for the bearings plus a can of new oil if you cock it up it's not the end of the world now is it.?

I wish mine had been £18.!! - Headstock bearings can run into the 100's and on larger machines 1000's £ per bearing.

Nick

This is probably your problem then. The tapered roller bearings need adjusting to take up wear. This is usually, but not always, done by tightening up a nut on the spindle to draw togethter the inner halves of the bearing at each end. You need to consult a manual for your lathe for the correct procedure. See also the ARCEurotrade website section titled ARTICLES for a rundown on one or two types of headstock rebuilds that should include adjustment. It's best to learn how to do the simple maintenance on your machine before you start thinking of totally disassembling and rebuilding it.