Vibration when turning

[Xim]

Hi All,

1st time on this site,

I have recently started turning again after a long break and I am experiencing vibration on the work in between the centers.

I turned a small spindle to accommodate my wedding ring so i could re-polish it. Using a skew the whole thing started to vibrate quite quickly.
That particular piece was an old broom handle turned down to approx finger diameter- total length 8 inches.

Also I made a rounders bat 16 " approx' length diameter from 2" down to 1" approx and during the narrower parts the vibration has caused almost like a barley twist effect.

Any ideas ?

Xim

 

[Paul Hannaby]

The problem is probably due to you putting to much pressure on the wood from the tool. Once the vibration starts, it tends to be amplified with each cut, causing the spirals you mention. Try the following - sharpen the tool, change the angle of approach and minimise pressure against the wood.

Alternatively, claim the spirals are an intentional "design feature" ;-)

 

[Dalboy]

The problem is probably due to you putting to much pressure on the wood from the tool. Once the vibration starts, it tends to be amplified with each cut, causing the spirals you mention. Try the following - sharpen the tool, change the angle of approach and minimise pressure against the wood.

Alternatively, claim the spirals are an intentional "design feature" ;-)

+1 for the above answer

 

[CHJ]

Next time any spiral bounce starts try using a sharp scraper on or below centre to remove the high points before you continue, thus preventing the ripple compounding the problem.

Also try using a spindle gouge or even a roughing gouge which will be easier to hold firm on the rest and less likely to follow any ripples due to reliance on location on the rest rather than the work piece (halfway house to the use of the scraper if you like)

I personally like to use a continental style spindle gouge for a lot of spindle work involving less than idea stock which can stretch my abilities with a skew.

 

[JimB]

All the above suggestions are good and probably will work. A couple more I use are to try a dead centre in the tailstock in case there is some movement in the bearings; the other is to use my smallest carbon steel skew (in my case an old marples). This encourages very fine cuts.

 

[Xim]

Thanks for all your replies, it seems to be accentuated the smaller diameter i get which implies too much pressure from the tool.
However even applying extremely light cuts it still makes a lot of noise, I must research a "dead centre".