Noob cant get the mandrel right

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CVPW

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Jun 27, 2010
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Ringgold Georgia
2 months ago I bought a penn state 10" commander lathe. I have had a lot of fun with it but they didnt include any instructions on how to set up and use the lathe. Every once in a while when I change the lenght of the rod it starts to get a wobble. Taking the mandrel out and putting it back can make it better or worse and I dont know what im doing that its making it change. Tonight the wobble was so bad that I blew 3 blanks before calling it a night. I took out the mandrel rod and rolled is on a flat surface and its straight. What can I do to solve this?
Thanks in advance. :redface:
 
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tim self

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If the mandrel is straight and your still getting a wobble, clean the seat where your mandrel seats. Just a small chip will cause severe wobble. It's been said a hundred times before but if you can, go to turning between centers. I don't think you can do it with 7mm kits but for all others it's possible.
 

Lenny

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go to turning between centers. I don't think you can do it with 7mm kits but for all others it's possible.

Actually Tim, johnnycnc has come up with a kit for turning 7mm pens between centers. It's called The 7mm Triple Play!
http://penturnersproducts.com/index.php?main_page=index&cPath=2_26

I know I don't have to tell you all what a great guy John is to do business with.... just check this forum and you will hear of him helping someone out on a daily basis. He recently tracked down some bushings I needed and included them in a recent order for no charge. Great guy and GREAT products!! :)
 

Lenny

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Searsport, Maine
2 months ago I bought a penn state 10" commander lathe. I have had a lot of fun with it but they didnt include any instructions on how to set up and use the lathe. Every once in a while when I change the lenght of the rod it starts to get a wobble. Taking the mandrel out and putting it back can make it better or worse and I dont know what im doing that its making it change. Tonight the wobble was so bad that I blew 3 blanks before calling it a night. I took out the mandrel rod and rolled is on a flat surface and its straight. What can I do to solve this?
Thanks in advance. :redface:

While it does sound like an issue with too much pressure on the mandrel from the tailstock or the (adjustable ?) mandrel slipping ...

Have you checked the alignment of the headstock to the tailstock by bringing the centers together and seeing how accurately they meet?
Is there any side to side play in the tailstock or does it lock down in the same position each time?
 

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jedgerton

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Austin, TX, USA.
This may be a long shot but I would check the morse tapers on both the head and tail stocks. Make sure they are clean and free of any lubricants. Wiping them out with a solvent of your choice will do the trick (I use denatured alcohol).

John
 

CVPW

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Ringgold Georgia
Thanks all for your help. I tried each suggestion and after taking a close look at the lathe itself it appears its the motor that is causing the wobble which in turn transfers the movement to the mandrel.
I guess im screwed. :mad:
 

Gary Beasley

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Marietta, Ga. USA
Thanks all for your help. I tried each suggestion and after taking a close look at the lathe itself it appears its the motor that is causing the wobble which in turn transfers the movement to the mandrel.
I guess im screwed. :mad:

If in fact thats the problem you need to replace the bearings in the headstock.
 

CVPW

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How does one go about doing this? There were no instructions included wit the lathe of any kind and none on their website (Pennstate).
Is there an online resource or better yet youtube vid?
 

witz1976

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Bucksport, Maine, USA
Thanks all for your help. I tried each suggestion and after taking a close look at the lathe itself it appears its the motor that is causing the wobble which in turn transfers the movement to the mandrel.
I guess im screwed. :mad:

Call Penn State if that is where you bought your lathe. It should be under warranty.
 

Gary Beasley

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You need to have some mechanical inclination and a few basic tools. Not seeing your machine I can't say exactly how it comes apart but the bearings are usually held in by ring clips and/or press fit into the head. A decent transmission mechanic could do it without breaking a sweat.
However I would be sure that is the real reason you are having this problem before tearing into the machine with a screwdriver. It could be an alignment problem, a loose mandrel or an overtight tailstock, or it could be a dull gouge making the blank jump and chip out.
 

Lenny

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Thanks all for your help. I tried each suggestion and after taking a close look at the lathe itself it appears its the motor that is causing the wobble which in turn transfers the movement to the mandrel.
I guess im screwed. :mad:

Call Penn State if that is where you bought your lathe. It should be under warranty.

I agree! Call them a Make them make things right. I think they should replace the lathe!!!!
 

MobilMan

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Mar 30, 2008
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Have you checked the mounting bolts on the motor? And you may also check the bolts that hold the headstock to the ways. If you find the headstock loose, align it to the tailstock before tightening the bolts.
 

CVPW

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Ringgold Georgia
Yes, I checked all that.
I took all the covers off and also the belt and ran the motor at it lowest speed and lightly placed a chisle against the pulley arm and could feel a definate chatter through the handle.Its the same frequency that comes though on the blanks as I try to turn them.
The head and tail stocks align perfectly.
 

CVPW

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Jun 27, 2010
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Ringgold Georgia
Does anyone have Skype that is willing to "come see" what is going on? It might help if someone that knows the nomenclature better than me to view the problem.
 

ctubbs

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Sep 12, 2010
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Murray, Kentucky
It may be a cast opposed to a turned pulley problem. Often cast pulleys are not truly concentric.

However, if this is new, contact your vendor and let them make the problem go away. DO NOT VOID YOUR WARRENTY!
 
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