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View Full Version : I think I have bent my Pen Mandrel



Ozkaban
11th May 2009, 03:37 PM
I know that this is a pen mandrel, but I did it turning a pepper mill, so I thought here was a good enough spot for it.

The thread could also be titled "Didn't follow manufactures advice" or "Lost concentration due to rushing" or even "That bloody hurt, but I consider myself lucky".

http://www.woodworkforums.com.au/attachment.php?attachmentid=104863&stc=1&d=1242015659

Anyway, here's how I did it...

I was turning a 10" pepper mill out of Tiger Myrtle (I think that's what it's called - sorry no pics) for my Mother in Law for Mothers day. Of course, I was doing this at about 11am, needing to have it finished for lunch, which was a 1 hour drive away, starting at 12:30... I had finished most of the mill, but thought that I would really like to polish the top knob a little better around the very top of it - my wooden mandrel/cone thingy didn't really let me get it done just right. So I looked around for something with a 6mm-ish shaft to mount on the lathe - voila! A pen mandrel! What a brilliant idea!

So I put the knob (it was about 65mm wide, 60mm tall, plus the tenon) on the mandrel. It was a nice tight fit, which was great. Brought the tail stock up and started polishing. Forgot to tighten the tailstock off. Note that pen mandrels have quite a shallow depression on the end, so a tail stock does not need to slacken off too much before it looses contact with the mandrel all together.

Anyway, the tail stock lost contact, a slightly off balance ball about the size of a tennis ball but quite a deal heavier starts wobbling around... a lot. I dived for cover but not before coping a nasty blow on the side of my wrist! Good news is that today I'm not so sure that I broke my wrist as I was yesterday afternoon... As the wobble got up to a rather frightful amount, I managed to hit the kill switch, the knob hit the lathe bed and went flying at Mach 2.5.

After it all stopped and I picked myself up, I finally found the knob - not destroyed but a nasty dent in the top of it. I called it "character" and decided that I didn't have time, wood nor inclination to do it again.. and was in too much pain!

Assembled the mill and gave it to MIL and she is delighted! I will take photos and post next time I'm over there. Lesson about locking tail stock off very strongly learnt, as is lesson about not rushing. At least until the next job is seriously late...

cheers,
Dave

DJ’s Timber
11th May 2009, 04:14 PM
Whoops :doh:

Skew ChiDAMN!!
11th May 2009, 04:25 PM
Wasn't someone just recently asking about off-centred pen turning?

Maybe they'd be interested in buying your 'modified' mandrel? :innocent:

ElizaLeahy
11th May 2009, 07:18 PM
You *think* you bent it?

I don't know - have you checked it with a level?

China
11th May 2009, 11:00 PM
Yep you bent it!

Ed Reiss
12th May 2009, 12:06 PM
...sounds like a mandrel manufacturing defect to me...sue

Ozkaban
12th May 2009, 12:11 PM
...sounds like a mandrel manufacturing defect to me...sue

:think: you might be onto something there!

Cheers,
Dave

Rum Pig
12th May 2009, 12:13 PM
You should be able to straighten that with a gentle tap from a hammer:;
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A Sludge hammer that is:U:doh: