Question from a new guy

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Serapheem

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Sep 20, 2019
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New York
So I thought that I had bent my pen mandrel and ordered another one. However I place it into the headstock and I am seeing the same wobble at the end that made me think the last one was bad. Is this wobble normal or do I have a dud lathe? Lathe is a less than three month old excelsior from rockler.
 
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leehljp

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Feb 6, 2005
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What kind of live center are you using? Is it a 60° live center? If you don't know about this, you should read up on it. It sounds like your cause.

1. Most pen lathes are WOOD lathes. Wood lathes come with a live center made for WOOD. The mandrel is METAL. When a live center that is made for Wood, is used in a mandrel, the point of the Wood live center does not match the Metal cup of the mandrel, it balls up into a tiny ball or bends and the mandrel wobbles.
2. You need a 60° live center.

3, If it is not that, you are probably pulling your tail stock up too tight.
4. OR the tail stock in not locked down,
5. OR the tail stock and head stock are not in alignment.

From your description, I would go with # 1 as my first choice.
 

magpens

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I think I understand what Hank (above) is saying.

The mandrel has a tiny "cup" on the end, and that "cup" is actually a 60 degree cone-shaped indentation.
The live center which you use in your tailstock should also have a 60 degree pointed tip as a match to the "cup".
When you buy a live center at a place that sells wood-turning lathes and accessories, they might sell you one that is more sharply pointed than 60 degrees. If the live center that you have actually came with the lathe, it is almost certainly too sharply pointed.
That could very easily result in the situation that you are experiencing, as Hank suggests.
You really do need a live center with a 60 degree cone-shaped pointed tip.

If you go to a place that sells metal-working lathes and ask for a live center, you will almost certainly be shown a 60 degree live center.
But you also have to be sure that the tapered shank of that live center is the correct one to match your tailstock.
The most likely taper to match your lathe will be a Morse taper #2 (MT2), but it could be a Morse taper #1 (MT1).

I hope you get this matter worked out because I really do understand how frustrated you must feel.
 

leehljp

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Here's what my mandrel looks like and the 60 degree live center.
Bobby, That which you posted is a mandrel saver, not a 60° live center.

60° live center:

Made for Wood live Center:

The one made for wood is more pointed and will bend or ball up on the very tip when inserted into the cup of a mandrel.
 

acmaclaren

Angi the Maker
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Oct 28, 2012
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Seattle WA
I turn on an Excelsior as well. I also use that exact mandrel saver. When you set your lathe up did you check to see if the headstock and tail stock lined up? They may need to be adjusted slightly.
 

bsshog40

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Oct 2, 2018
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Midland, Tx
Bobby, That which you posted is a mandrel saver, not a 60° live center.

60° live center:

Made for Wood live Center:

The one made for wood is more pointed and will bend or ball up on the very tip when inserted into the cup of a mandrel.
Duh, you're right.
 

Taylorrock99

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Oct 28, 2019
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7706 spring valley ave
I am new to pen turning as well. Could this cause your pen to have a very very slight essentric turn to it? I notice at the bushings, one side is good and the other is just slightly off. Or am I drilling my holes at a slight angle?
 

More4dan

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Katy, TX
Worn bushings or new ones that are loose can also be the cause of eccentric turning. I gave up using a mandrel pretty quickly and now turn between centers. Many wood blanks can also become eccentric while sanding due to variations in hardness. Using a hard block behind your sand paper can help. As a quick fix you can turn the one side that stays round to the bushing then reverse the blank on the mandrill and turn the other side.
 

hbillings

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Dec 26, 2018
Messages
130
Location
Dallas
I am new to pen turning as well. Could this cause your pen to have a very very slight essentric turn to it? I notice at the bushings, one side is good and the other is just slightly off. Or am I drilling my holes at a slight angle?
I've also noticed this when the barrel ends were not squared properly. When I first see the issue I take it off and sand it very lightly in my disc-sander jig to square it up and that usually works.
 

rherrell

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Aug 22, 2006
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Pilot Mountain, NC
Get yourself a dial indicator and you can "tap" on the mandrel with a small hammer to get it running true BEFORE you hook up the live center,

EXAMPLE...

1574853566997.png
 

mick

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Mar 13, 2005
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Decatur AL, USA
Are you using a mandrel mounted on a #2 morse taper? Or inserted in a collet chuck? If it's the Morse taper make sure there's no dirt or foreign matter inside the opening before you insert the mandrel. This can cause a mandrel to wobble and appear to be bent.

Sent from my SM-G955U using Tapatalk
 

jttheclockman

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Feb 22, 2005
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NJ, USA.
Are you using a mandrel mounted on a #2 morse taper? Or inserted in a collet chuck? If it's the Morse taper make sure there's no dirt or foreign matter inside the opening before you insert the mandrel. This can cause a mandrel to wobble and appear to be bent.

Sent from my SM-G955U using Tapatalk
Hello Mick not to be the negative guy here and we all know you have been away from the site for a time, but you keep opening old threads that have been answered and some of the people do not show up any more. It is nice you are looking back but start your own threads so we can all comment on new material. This is just a friendly point of interest. :) :)
 
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