Flexispeed Meteor 2

[James AParticipant @jamesalford67616]

Does any of your centres fit? If not, I could measure the dead centre that came with mine. That fits and might help you with your centres.

James.

[James A]

On James A Said:

Does any of your centres fit? If not, I could measure the dead centre that came with mine. That fits and might help you with your centres.

James.

Hi James, that would be great ! Thank you.

 

Regards Sandra

[ferroequinologist]

On ferroequinologist Said:

On James A Said:

Does any of your centres fit? If not, I could measure the dead centre that came with mine. That fits and might help you with your centres.

James.

Hi James, that would be great ! Thank you.

 

Regards Sandra

I shall measure them when I go out there next, probably tomorrow.

James.

[ferroequinologistParticipant @ferroequinologist]

Hi all

after proper oiling and setting up, my Flexispeed is still vibrating a lot. The belts are aligned, but I wonder if it is too much tension in the V-Belts, which are new? Or the motor is just too heavy on the hinge. I was wondering if I should either mount the motor under the bench like Roderick did or put it into an anti vibration cradle as Mark did or simply get a sliding motor mount like this?

Regards Sandra

[SillyOldDufferModerator @sillyoldduffer]

Look for the source of vibration:

• Does the motor vibrate when run without a belt?  If so, faulty motor, perhaps a shorted winding.  Also ensure the shaft turns without wobbling – might be bent.   Replace the motor if it vibrates badly.
• Again without the belt, turn the lathe over by hand feeling for binding.   If found, look for the cause – gears too close together (easy adjust – should be apart by the thickness of a sheet of paper, maybe doubled).  Or might be something nasty like a worn or bent spindle or knackered bearings.
• Put the belts back on and check they are aligned.  (See below)
• Take the chuck off and run the lathe.  If the vibration stops, check the chuck for balance and that it’s correctly attached to the spindle.  (Worn thread, cross-threaded, dinged register etc.)   Dud chuck is unlikely to cause vibration unless a jaw is missing, or they’re wildly off centre.
• Does anything wobble visibly when the lathe is spinning?
• Might be possible to identify the source by listening.  Ideally with a stethoscope, but a wooden rod works too.   Be careful  not to get hair, rings, or clothing caught in a running lathe.  Think scalping, fingers ripped off, and face pulled into steel gears.
• Run the lathe with the leadscrew disengaged.  If the vibration stops, inspect the leadscrew – they are easily bent.   If so, take it off and straighten it.  (Ask if necessary.)
• Worn spindle bearings.  With power disconnected put a 300mm length of 25mm diameter pipe in the chuck as a lever.  Waggle it up/down, side to side and fore-and-aft.  Chuck and spindle shouldn’t move in those directions, only rotate.  Severe wear might be visible, but best measured with a DTI.

Alignments. Can’t tell from the photo of the new arrangement, but the original layout looks off.   The pulleys have to be aligned at right angles and the motor looks off.  The red line suggests the motor and intermediate pulley are misaligned: the motor is a bit off, fore-and-aft and not at a right angle.

The green line between the intermediate shaft and the lathe pulley look reasonable, but cameras can distort reality.  Check the equivalent alignments in the new build with a straight-edge and square. With luck the vibration is due to misaligned pulleys because the fix is just an adjustment, no need to replace faulty parts.

Good luck,

Dave

 

[DiogenesParticipant @diogenes]

Is this with the four-jaw chuck still on it?

[ferroequinologistParticipant @ferroequinologist]

Hi Dave

 

thank you so much for your detailed list, I will hop into my workshop now and look at all these options and will report !

 

@Diogenes, yes four -jaw chuck is on and completely closed so it doesn’t run unequal.

[ferroequinologistParticipant @ferroequinologist]

Hi Dave

all checks completed. The belts are in line, measured with square and laser, the motor runs very smoothly on its own and is very quiet . Astonishing with that age ! Listened to lathe and everything runs very well ( I think the lathe did not see much action to be honest) .

However, put all back together I have found that the motor on the hinge bounces up and down and transfers the vibration to the lathe. I have supported the hinged board with a long aluminium spirit level ( don’t ask, it was just nearby 🙂 )  underneath and the vibration is almost gone ! So if I support the hinge it seems much better. There is a sweet spot where the tension seems enough before it starts making noises ( belt tension too slack I believe) . It defeats the object to support the hinge with motor and countershaft, but I can’t think of anything else.

Thanks Dave

Regards Sandra

[Grindstone CowboyParticipant @grindstonecowboy]

My bench model Boxford has a bolt with a spring arranged to give a bit of pre-load to the hinged motor platform i.e. it pushes it down a little, assisting gravity and limiting uncontrolled upward movement which would slacken the belt. Maybe a similar idea would help in your case?

Rob

[James AParticipant @jamesalford67616]

I have measured the centre that came with my lathe. It is 7.06mm at the narrow end. It is 7.89mm at the other end. It is 28.34 between the two.

My motor is fixed. I use a roller bearing on an arm, the arm pressing down on the belt to take up the slack.

James

[DiogenesParticipant @diogenes]

Re motor mounts – Myford (and others) used a slotted metal strip between the base and motor platform so that they could be locked in position with a little tension on the belt.. ..I’ve seen others with just a threaded stud & nuts arranged to pull the platform back against the belt..

As you say, V belt drives always have a sweet spot where belt tension is just right, and I think you will have to figure some means of positively securing / ‘locking’ the motor platform at that point.

 

 

[James A]

On James A Said:

I have measured the centre that came with my lathe. It is 7.06mm at the narrow end. It is 7.89mm at the other end. It is 28.34 between the two.

My motor is fixed. I use a roller bearing on an arm, the arm pressing down on the belt to take up the slack.

James

Thank you James, very helpful. I have found a photo of your set up in a thread from a couple of years back. Very inventive ! I will look into that as it is indeed taking the equation out of the weight of the motor and the faffing with the countershaft.

[Grindstone Cowboy]

On Grindstone Cowboy Said:

My bench model Boxford has a bolt with a spring arranged to give a bit of pre-load to the hinged motor platform i.e. it pushes it down a little, assisting gravity and limiting uncontrolled upward movement which would slacken the belt. Maybe a similar idea would help in your case?

Rob

Hi Rob, have you got a photo please? I have seen springs on other set ups, but I can’t imagine how big the spring must be to counterweight the bounce? ( Beginner’s brain)

[Diogenes]

On Diogenes Said:

Re motor mounts – Myford (and others) used a slotted metal strip between the base and motor platform so that they could be locked in position with a little tension on the belt.. ..I’ve seen others with just a threaded stud & nuts arranged to pull the platform back against the belt..

As you say, V belt drives always have a sweet spot where belt tension is just right, and I think you will have to figure some means of positively securing / ‘locking’ the motor platform at that point.

 

 

Another good idea, well here is food for thought ! Thanks all.

[ferroequinologist]

On ferroequinologist Said:

…However, put all back together I have found that the motor on the hinge bounces up and down and transfers the vibration to the lathe. …

Well done, I think you’ve cracked it!  I didn’t think the motor might be bouncing on the hinge because the mounts on my belt-driven tools all lock the motor.

Diogenes puts it well, my bold:

On Diogenes Said:

Re motor mounts – Myford (and others) used a slotted metal strip between the base and motor platform so that they could be locked in position with a little tension on the belt.. ..I’ve seen others with just a threaded stud & nuts arranged to pull the platform back against the belt..

As you say, V belt drives always have a sweet spot where belt tension is just right, and I think you will have to figure some means of positively securing / ‘locking’ the motor platform at that point.

 

 

Tension spring, clamping the hinge, support underneath etc.      Slots as suggested by Diogenes would be my first port of call, but this isn’t a problem I’ve solved myself.  Might have to experiment. Someone with an older back-shaft driven lathe should be able to advise; the arrangement used to be common.

For completeness, another cause of vibration on old machines is belts taking a set.  The rubber hardens into a stiff loop which bumps.  Caused by being left for yonks in the same position on the pulleys and not unusual on machines that have been in long storage.   Didn’t list it because your belt is obviously new.

Dave

 

 

 

 

 

 

[James AParticipant @jamesalford67616]

Sandra.

I was wondering whether you have had any luck or success with the 0 Morse arbours that you bought. Have you managed to do anything with them?

 

James

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