Got a problem

[4x4redneck]

I am havin a problem with my lathe. My last bout 3 or 4 pens have come out off centered. I have changed out my mandrel, drilled perfectly, and tried everything. Does anyone have any idea what it could be, im lost. For anyone who might be wondering its an ole record 300c. Can someone please help.

 

[ed4copies]

Check your bushings---is the hole off-center?

 

[Monty]

Check and make sure the headstock is inline with the tail stock. Also make sure your bushings are not drilled off center.

 

[4x4redneck]

they were different bushings for different types of pens. i did a center to center check and its dead center, but with a mandrel is a whole diff story. it doesnt spin right

 

[Phunky_2003]

Take the mandrel and roll it on a flat smooth surface. See if it is warped.

 

[ed4copies]

they were different bushings for different types of pens. i did a center to center check and its dead center, but with a mandrel is a whole diff story. it doesnt spin right

So, when you run it with nothing on it, the mandrel "wobbles"??

Is it bent in the middle--ish??? We CAN fix--just figure out if this is the problem.

Put your tool rest right up next to the mandrel (.25" away) to determine if the mandrel gets closer and farther away as it turns (BENT)

 

[4x4redneck]

i have 3 mandrels 1 brand new used it for the first time today and it did it on that one 2. i can usually figure things out but this one has me stumped. thank yall ahead of time for tryin to help me with this

 

[Phunky_2003]

Are you over tightening the mandrel that can cause problems. I'd say chunk it all and start turning between centers....... lol problem fixed

 

[ed4copies]

Clean the Morse Taper in the headstock

 

[4x4redneck]

i was thinkin it could be the bearings or somethin with the machine, that was my last option. wish i knew how to turn between centers, been doin this off and on for a few years and aint never done it

 

[mick]

I hate to ask but are you turning with sharp tools? Is it possible that you're putting too much pressure on the blank and that's bending the mandrel? I had ask since the newer mandrel did it too.

 

[4x4redneck]

i dont use much pressure, all my tools just got sharpened, i try to keep them pretty sharp. i went outside a little bit ago and turned the headstock by hand, i just put the mandrel back on to test it and the mandrel was turning in an oval , i cleaned the morse taper to see if that was it and that didnt work

 

[Monty]

Throw the mandrel away and turn between centers. That will get rid of any OOR you may have that is being caused by the bushings.

 

[4x4redneck]

ill have to try it any pointers on how it will be a first

 

[Monty]

ill have to try it any pointers on how it will be a first

From the IAP library - http://content.penturners.org/articles/2010/turningbetweencenters.pdf

 

[4x4redneck]

it is much appreciated i will try doin that. thanks for all the suggestions on how to fix the problem

 

[Monty]

it is much appreciated i will try doin that. thanks for all the suggestions on how to fix the problem

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