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.
Question from a new guy
- Thread starter Serapheem
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leehljp
Member Liaison
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.
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.
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.
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
Member Liaison
Bobby, That which you posted is a mandrel saver, not a 60° live center.
60° live center:
Live Center - MT2 with Taper Bearings - Grizzly Industrial, Inc.
Perfect for just about any turning requirement, these dust, chip and oil proof live centers feature 60° included angles and pre-loaded taper bearings. Type: MT #2.
www.grizzly.com
Made for Wood live Center:
Cupped Live Center for Wood Lathe - MT2 - Grizzly Industrial, Inc.
<h1>H3404 MT2 Cupped Live Center for Wood Lathes</h1> <h2>Benefit from enhanced lathe workpiece support.</h2> <p>Cupped live centers provide better grip and prevent splitting of a workpiece in a lathe.</p> <p>The all ball bearing construction results in very little turning resistance even when...
www.grizzly.com
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
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.
Duh, you're right.Bobby, That which you posted is a mandrel saver, not a 60° live center.
60° live center:
Live Center - MT2 with Taper Bearings - Grizzly Industrial, Inc.
Perfect for just about any turning requirement, these dust, chip and oil proof live centers feature 60° included angles and pre-loaded taper bearings. Type: MT #2.
Made for Wood live Center:
Cupped Live Center for Wood Lathe - MT2 - Grizzly Industrial, Inc.
<h1>H3404 MT2 Cupped Live Center for Wood Lathes</h1> <h2>Benefit from enhanced lathe workpiece support.</h2> <p>Cupped live centers provide better grip and prevent splitting of a workpiece in a lathe.</p> <p>The all ball bearing construction results in very little turning resistance even when...
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.
Taylorrock99
Member
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?
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.
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
Member
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...
EXAMPLE...
mick
Member
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.
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jttheclockman
Member
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.
