# How tight to tighten my mandrel?



## scjohnson243 (Jul 3, 2014)

So I watched a few videos and they mentioned that you need to be careful with the pressure you press on your mandrel or it could snap/warp/die.. When i first started turning my first pen if I put any pressure on the blank from my gouge it would just quit spinning... I kept slowly tightening it down harder and harder (from the screw on the end of the mandrel) and after a while it kept spinning, but I was scared I was about to break something.... It *IS* okay to tighten up on the nut at the end of the mandrel that presses on the bushings really tight, right? they are talking about applying a lot of pressure from the tailstock on the mandrel, right?


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## jcm71 (Jul 3, 2014)

You got it right.  It is OK to tighten the nut to keep your blanks from slipping.  You should be able to spin your live center by hand after you tighten the tailstock.  A good investment for you will be to buy a mandrel saver.  Insert that into your tailstock instead of the live center, and then you have no need for the knurled nut.  Follow on investments may include (not all inclusive) a dead center and Turn Between Center (TBC) bushings for the style pens you are making.  Good luck.


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## scjohnson243 (Jul 3, 2014)

BURLMAN said:


> You got it right.  It is OK to tighten the nut to keep your blanks from slipping.  You should be able to spin your live center by hand after you tighten the tailstock.  A good investment for you will be to buy a mandrel saver.  Insert that into your tailstock instead of the live center, and then you have no need for the knurled nut.  Follow on investments may include (not all inclusive) a dead center and Turn Between Center (TBC) bushings for the style pens you are making.  Good luck.



Thank you Burl, I keep hearing about the TBC bushing and such, but will need to look it up and do some research... I will probably give it a few weeks to let my pocketbook recover.


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## GRMiller (Jul 3, 2014)

Oh Oh Oh your pocket book will not recover lol.  The beauty is all the ground work is done so you can make inform decision on spending.  I was just getting ready to buy some gauges and now PSI tossed there new ones in the fray.  Better get back on track here that the best available info is right here for noobs


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## Edgar (Jul 3, 2014)

+1 on the Mandrel Saver!

Turning one blank at a time with a mandrel saver, accomplishes the same thing as turning between centers - you just have a rod going through the blank. No need for additional special centers or bushings other than the mandrel saver itself - and you still have the option of turning two blanks at a time if you want to.

Blank mounting/dismounting time is slightly longer with a mandrel saver than with TBC, but it's only a few seconds and for those of us who aren't into production turning, it's no big deal.


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## Bear-31 (Jul 3, 2014)

From your original post the warnings that you had heard usually refer to one specific procedure. When installing your mandrel make sure and leave the knurled not loose until after you have seated your morse taper and tightend your tailstock. Then tighten your nut holding the blanks.
 Reasoning - If you tighten the nut first then apply pressure with the tail stock you actually apply even more pressure to the mandrel and blanks than first intended....which can cuase you to warp the mandrel. You would really have to crank on it to break it.
 +1 on the mandrel saver. Only downsdie I have found to the mandrel saver is when working on a short blank it reduces the working area between the head stock and tailstock. I have to use my 4in tool rest and sometimes have difficulty getting my tools in at the prefered angle without hitting one or the other....caveat - My go to tool is a 1/2in swept back bowl gouge for turning pens, which is larger than most.


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## scjohnson243 (Jul 3, 2014)

edohmann said:


> +1 on the Mandrel Saver!
> 
> Turning one blank at a time with a mandrel saver, accomplishes the same thing as turning between centers - you just have a rod going through the blank. No need for additional special centers or bushings other than the mandrel saver itself - and you still have the option of turning two blanks at a time if you want to.
> 
> Blank mounting/dismounting time is slightly longer with a mandrel saver than with TBC, but it's only a few seconds and for those of us who aren't into production turning, it's no big deal.



Considering I have turned all of 1 pen, I'm fairly far away from a production run or two.  

It will be at least a month or two before people whisper my named in hushed tones all around the pen turning world...

I mean, that or I'll just quit destroying blanks... either or.


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## monophoto (Jul 3, 2014)

My name is whispered in hushed tones also - but for other reasons.


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## Shock me (Jul 12, 2014)

Another +1 on Mandrel saver or TBC

For what you are now using, however, yes it is possible to apply too much pressure with the nut or tail stock to cause bending of the mandrel or breakage of a brittle blank. I've done both.  

Your gouge will stall the blank if it is too loose or if you are trying to cut too aggressively. So it's a lot about feel, tighten the nut and tail stock until your light touch doesn't stall the blank. The tightness you need will vary with the material you are turning.


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## Paul in OKC (Jul 12, 2014)

It is NOT possible to bend the mandrel by over tightening the nut. You are actually pulling on the mandrel, so to speak. You would strip the threads out of the brass nut before that happens. Not sure how folks have come to this conclusion, but...... Your mandrel is a piece of rod, and metal has its own characteristics that can cause it to bow, but that is another story. I have used a mandrel almost exclusively in my turning for the last 15+ years with no problems. TBC is an excellent alternative and have done that as well. Make sure your blalnks are pen milled or what ever to be squared and perpendicular on the ends as this can cause issues like spinning blanks or a "wobble" from the pressure on the ends not being even.


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## ottotroll (Jul 12, 2014)

Buy the mandrel saver - $15 or so at Woodcraft - it is worth it for us "newbies"....


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