aarrrggggghhh vibration problems

[treefella83]

i have a record power cl 1 mounted on a very sturdy bench which is bolted to a concrete floor and both the shelves under the lathes are packed with large lumps of timber so i don't think that weight is a problem but trying to turn any face work i get stupid amounts of vibration no matter how gentle i am with the bowl gouge.
this has been a long running problem ever since i purchased the lathe over a year ago.
basically any timber on the lathe that is not supported by the tail stock will vibrate even bottle stoppers 2 inches long.
i have been in contact with record power many times and i have replaced the drive belt, bearings and even purchased a new motor and pulley wheel to see if that was the problem.
the lathe does not vibrate when running only when i apply a tool.
after reading a thread a few months ago about this sort of problem i placed a length of 10mm steel plate between the lathe and the bench to stop the lathe sinking into the bench as the bolts holding the lathe down were very tight but still the same problem.
the bench has been bolted to the wall and left free standing but still the same problem.
only tonight have i noticed that a gentle tap with the palm of my on the headstock or tailstock and the whole lathe will gently vibrate.
this is a long story without a happy ending does any one out there have any ideas?
i'm starting to think that my bench is the problem and i'm looking at getting the lathe stand supplied by record power to fit the cl1.
before i spend any more money can anyone think of anything that i could have missed any advice would be very helpful.
i keep telling myself that woodturning is a weekend hobby over and over again. thanks jon

 

[Wanlock Dod]

Have you considered a piece of fairly hard rubber between the lathe and the bench? No idea where you'll find such a piece, although Rowley seems to recommend a piece about 6mm thick in his "Foundation Course".

Cheers,

Dod

 

[Russell]

Where are you are you near J27 of the M62

 

[treefella83]

cheers i will try some rubber as we have loads of offcuts from the floors in horse boxes we build.
and i live in bishop auckland no where near the m62 sorry

 

[Russell]

A little far to come up for a look

How are you holding your work, face plate or chuck, if you are using a chuck which chuck.

 

[paulm]

Sounds like either the bench is not rigid enough, or the the lathe bars are not mounted securely or squarely on the end pieces.

Have you tried unbolting the bars from their supports and then reseating and tightening them making sure there is no flashing or lumps of paint or anything preventing them from tightening up fully and evenly ?

Likewise check the seating of the headstock assembly on the bars.

Also check that the bench surface that the lathe bolts to is even and in line both ends with no twisting that might distort the bed bars and their alignment.

Does the vibration happen when using drive centre, face plate or chuck or all three ? May not be the lathe but could be an issue with the way the work is mounted ?

Just some more things to check out if you haven't already, good luck !

Cheers, Paul.

 

[treefella83]

the lathe does not vibrate at all when turning between centres but when any work is not supported by the tailstock thats when the trouble starts.
i use 2 different chucks a supanova and an old bonham lever scroll chuck and its the same problem if the work is held in the worm screw or any of the jaw sets i have spigot or dovetail and even with a face plate.
and i have taken the lathe apart twice making sure that every thing is correct using 3 spirit levels on the bed bars.
thanks for your replies.

 

[Russell]

You said the head stock vibrates when tapped with your hand do you mean like a bell. If so unbolt head stock leaving the base plate on the bars (I can’t remember if this lathe has a separate disc that sits on the base plate between the base plate and head.) If so remove this disc and clean off any thick grease. The base plate should have a fine film of grease and no more. If no disc then there is a disc cast in to the base of the headstock check this is not over greased. When you reassemble bed the head in by rotating to disperse the grease. Ensure that the convex and concave faces of the saddle under the bed bars match the contact lugs on the base plate a single lug opposes a concave surface giving 3 contact points on the bar and the double lug side having the convex face opposing again giving 3 contact points on the bed bar. I am assuming at this point bed bars are parallel, level and locked in the end supports again ensuring 3 contact points on each bar (the saddles again have concave and convex faces and the end supports 1 or 2 lugs that the bars sit on)

When you lock the lathe head down the nut on the inside of the head stock will either sit in a groove the width of the nut or in newer models a split pin will stop it rotating. A problem can occur here if the nut is not allowed to sit square over the hole. I have had instances where the split pin is positioned incorrectly preventing the nut from seating properly if this is the case this may cause you vibration because the lathe head is not held as securely as it should be. When the nut is sitting correctly tighten up the lathe head and check alignment (point to point) to ensure head stock and tail stock are the same height.

When bolting record lathes to a wooden bench I like to ensure the lathe is on metal plates under each bed support to stop the lathe bruising the wood. The wood under the metal must be smooth (rough saw or unfinished timber does not give a good enough surface) a piece of kitchen work top is ideal. You must also use the large disc approc 3” supplied with the lathe under the bench to distribute the clamping load from the bolts as they are tightened. Ensure when you lock these down you don’t twist the end supports as this will put tension into the bed bars.

If you are happy that the bench is secure, rigid and as solid as possible the vibration if It occurs is in the lathe then follow the points below to try and isolate the problem.

Working on end grain and unsupported by a tail stock will cause the timber to resonate hence set up a vibration. The lathe you have should handle that easily and from what you have said it seems to me that you have gone through most of the options. I have dealt with this issue before with a CL1 and also a CL3. In the case of the CL1 we changed the bearings twice but did not use bearings supplied by Record we used high quality industrial bearings.

1) With out any work on the lathe and the lathe set to middle speed with belt tension set as per normal. Place a large screw driver tip as close to the bearing as you can without touching any moving parts. Place the other end of the screw driver against your ear and listen to the bearing it should sound smooth without any rumble or grating. Do this with both bearings if they don't sound smooth replace them.

2) Place a face plate on the lathe and position the tool rest so it almost touches the outer face at the edge of the face plate. WITH THE LATHE TURNED OFF rotate the face plate and check the gap between the rest and the face plate is constant. You can also try this with the chuck again with the lathe off. Excessive movement will mean inaccurate chucks and face plate or the register/ thread on the head stock is not accurate or the head stock spindle is bent. Test face plate and chuck on a different lathe if you can to eliminate it. To solve this problem may require a new head stock spindle.

I have been working with and selling Record lathes for 7 years so all of the above are tried and tested set up methods I have developed for solving customer’s problems. If you weren’t so far away I would have come and had a look but instead I wrote a book :lol: hope this helps.

 

[paulm]

Having thought about it some more, and although you have already changed the bearings (both?), the fact that when supported by the tailstock the problem goes away, does suggest to me that there may be play in the bearings which is taken up when you tighten against the workpiece with the tailstock.

Or as Russel has mentioned regarding the bolt arrangement that anchors the headstock, again any play in that would be taken up by tightening the tailstock.

Think you probably have the answer in and amongst the the last few posts somewhere, let us know how you get on !

Cheers, Paul.

 

[treefella83]

i big thankyou to everyone .
this weekend i took the lathe apart and took it off the bench and have found out that the bench vibrates ever so slightly when tapped with my hand.
the funny thing is that i purpose built the bench to be solid and heavy and each leg was bolted to a concrete floor and at one time this year bolted to the wall behind.
i still cant understand why the bench vibrates like it does, may be i'm a bit too fussy but as things were i could not progress with my turning.
a friend of mine has his lathe (a nova dvr ) fixed to a length of kitchen work top which is fixed to the wall and supported by 2 wooden legs i might try that idea or just buy the lathe stand from record power.
once again thanks everyone.