Advice please

[jethro110]

hi all,

im new to wood turning and this forum.

I need a little advice on the following:-

ive purchased a DML18SH-SK Record Lathe and a chuck to go with it.

once i have turned my blank on either the prong drive or woodscrew chuck, i make a tennon for the chuck but when i insert the blank into the chuck, it always seems to turn off center with a lot of vibration, am i doing something wrong? everytime i watch projects on YouTube nobody seems to have this issue?

PS nobody seems to discuss their failures and near misses when a project flys off and tries to take your face with it?! (hammer)

 

[CHJ]

What Chuck and what accessory jaws have you got?

Are you using a dovetail spigot or socket for your chuck jaws to grip?

Some images of your prepared piece awaiting mounting and mounted on your chuck would help diagnose your problems and aid any advise.

 

[Woodchips2]

Hi Jethro
Welcome to the forum.

It sounds like you're not bedding the blank tight against the chuck. You need to push the blank firmly against the chuck while you tighten the jaws.

Regards Keith

 

[NickWelford]

You do have a scrolling chuck and not an engineering chuck, I hope

 

[jethro110]

Thanks for the replies
its an SC3 chuck and im using the dovetail spigot. My blank tennon also has a dovetail on it and im using the tail stock to hold it in place when i tighten the chuck to ensure its tight and inline. Ill take some pics tomorrow

cheers

 

[Dalboy]

I see that the lathe has a swivel head, before you turn a spindle or anything between centres do you check the head and tail stocks are in fact in line. I do this on my CL3 by putting the 4 prong in the head stock and the revolving centre in the tail stock bring them up together and check they are in line. I do this every time I swivel the head stock for turning bowls and the like.

 

[woodpig]

Couple of things spring to mind. Have the accessory jaws been correctly fitted on the chuck and have you turned the spigot to the recommended diameter?

 

[Silverbirch]

Are you using cross grain blanks, with the object of making bowls etc? It may be that your tools are not sharp, or are being presented to the work incorrectly, causing vibration and catching, which could unseat the work from the chuck.
Long grain (spindle) blanks can also be mounted in the chuck , if you need to work on one end,such as when hollowing for example. In this case you can bring up the tailstock to align the blank, using the centre mark left from the original mounting. You might need to skim a little off the surface and then you can remove the tailstock if required. The blank should then run true.

 

[Paul Hannaby]

First check the chuck - if you close the jaws do they all touch each other? If so, they are fitted correctly and are concentric.

Second, check your spigot - is it running true when you have it between centres?

Third, check the length of the spigot - it should be slightly shorter than the depth of the chuck jaws.

If all the above check out, you are probably over-tightening the chuck and distorting the spigot. (Are there deep jaw marks in the spigot after it has been in the chuck?)

 

[jethro110]

Thank you everyone for all your advice ill go and have a look

merry christmas

Jeff