# Bent Mandrels



## Randy_ (Jan 28, 2007)

This subject gets a lot of play here; but I wonder how many folks have ever really had a bent mandrel.  There are lots of things that can cause problems and give results like a bent mandrel might; but the simple fact is that a mandrel is nothing more than a short steel rod with some threads cut on one or both ends.  They are really pretty sturdy tools and it is hard for me to believe there are as many bent mandrels out there as there are discussions about them.  So the question is: 

Have you, personally, ever had or bent a pen mandrel??


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## stevers (Jan 28, 2007)

Only turned 100 or so pens, but haven't done that yet. I have wrapped rags around the blanks now that I've started wet sanding.


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## jcollazo (Jan 29, 2007)

With my very first mandrel I put so much pressure in sanding that I bent it after 8-10 pens. I then learned to let the sandpaper do the work. Also, learning how to effectively use the chisels so that less sanding is necessary comes in to play.


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## Pipes (Jan 29, 2007)

I have helped a couple a guys to learn to turn and IMO the BIGGEST mandrel bending problem is new guys wana tighten down to hard on the live center end  just my 2 cents !! 


pipes


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## Monty (Jan 29, 2007)

Not bent, but I musta got some CA on the MT end of one. I twisted it off and now I have a MT with a piece of steel in it. Tried soaking it in acetone, nope. Tried to drill it and use an EZ Out but no luck,it's still in there.


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## tas2181 (Jan 29, 2007)

Never had a bent mandrel yet.(Little over a year of pen making)
I lay my finger on the live center with moderate pressure and turn the hand wheel on the headstock when tightening. When the live center just turns with the mandrel it is tight enough. (If it is not tight enough you will wear a groove in the live center tip.)DAMHIKT


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## Penmonkey (Jan 29, 2007)

I've had a few on my shopsmith but I don't use it anymore.


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## Tanner (Jan 29, 2007)

I did that little trick that Russ teaches in his video with a wire to check wobble in the mandrel and mine was a little off.  I just pushed on the mandrel until the end of the wire was exactly the same distance from the mandrel all the way around.  I was pushing too hard when sanding.  Now I go with light not white (knuckles), when sanding.[]


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## Rifleman1776 (Jan 29, 2007)

I voted yes because I had a defective mandrel once. I came new with the tail end off center. Whether it was bent at the Morse taper or whether the taper was incorrectly drilled (my guess at what the problem was) I'm not sure. I sent it back.


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## Randy_ (Jan 29, 2007)

> _Originally posted by Monty_
> <br />Not bent, but I musta got some CA on the MT end of one. I twisted it off and now I have a MT with a piece of steel in it. Tried soaking it in acetone, nope. Tried to drill it and use an EZ Out but no luck,it's still in there.



Mannie:

CA softens up quite a bit when heated.  If you still have that arbor, heat it up with a propane torch or maybe even with a good hot hairdryer.  I think around 200Â° is the "tipping point" so a pot of boiling water should work, too.  Try the EZ out on a hot arbor and see if that will solve your problem.


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## RussFairfield (Jan 29, 2007)

I have had mandrels with threads that were off center and at an angle to the rod. I have had MT adapters where the tapped hole was off center and crooked. I have had mandrels whose center was drilled off-center. I have had live centers that weren't even close to "center". But, I can't remember ever having a bent mandrel other than the one I stepped on, and that was straightened. 

I have never bent a mandrel by overtightening the knurled nut, or from the bushings and blanks not being square. I guess it could be done; but I have never done it, and I have no way of relating to anuone being able to do that. 

And, I am not saying that there aren't bent mandrels being sold. I have never bought one of them.


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## kent4Him (Jan 29, 2007)

Okay, I admit it.  I have a few.  I think part of my problem has been not using a 60 degree live center.  I used the one that came with the Jet.  Bad move on my part.  I also bought the Beall Collet Chuck.  Hope I have seen the end of bent mandrels.


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## TellicoTurning (Jan 29, 2007)

I voted not sure... I was getting some out of round on my first mandrel... don't know it it really bent, but replaced it anyway...


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