Penmill problem - leaving burr

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underdog

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Sep 11, 2006
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Watkinsville, Georgia
I'm having a problem with my pen mill. When I'm milling prepped blanks, I just "kiss" the end of the tube with the mill, and it leaves a burr on the tube. There's evidently too much space between the shaft and the blades which lets that part of the tube remain uncut.

What's the solution?:confused:
 
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monophoto

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Mar 13, 2010
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Saratoga Springs, NY
I've had a similar problem. The barrel trimmer trims the end of the blank, but it leaves a very thin bur, somewhere between 1/3 and 1/2 the thickness of the tube, at the end of the tube.

Because the bur is so thin, you can use a reamer to remove it.

A reamer can be anything - a countersink tool in a handle, a knife blade, even a screwdriver blade.
 

StephenM

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Apr 16, 2011
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Webster Groves, MO
I use a countersink - don't even need a handle just hold it and give it a turn and it will clean it right up.

I was cleaning up the shop the other day and found my grandfather's countersink for a brace. I think I'm going to make a handle for it and use it as a dedicated tool on every blank.
 
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butchf18a

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Dec 3, 2010
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woodland, wa
Like many others I too have had that problem. Counter sink works, but I went one step further. I wrote to the manufacturer. I'd like to report they are fixing it, but can't. I never got a reply. I'd encourage others to write expressing dissatisfaction, squeaky wheel gets the grease.
 

76winger

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Aug 30, 2009
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Lebanon Indiana
I keep a small X-Acto knife on hand to trim the tubes of burs as well as glue that gets on the insides of the tubes.

+1 Works great. Just don't cut away too much or you'll get a slip fit for the components (unless you want to do that).

Yep! When the scrapings turn yellow-metallic instead of whitish-clear (glue), you've gone too far.
 

pianomanpj

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Sep 24, 2007
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Augusta, Maine, USA.
The chamfering tool from AS is my go-to tool. I use it even if there is no burr. By chamfering the tube before assembly, you can better align the components and help minimize the risk of cracking your blanks.
 

underdog

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Sep 11, 2006
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Location
Watkinsville, Georgia
Mike... what is "PR release"?

Hey all... thanks for all the good info. I especially liked the idea of a smaller 3/16" shaft on the mill. That would take care of the problem before it happened. No need for the chamfer tool then...
 
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nava1uni

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Mar 30, 2008
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San Francisco, CA, USA.
If you don't trim the blank too much trim the tube you won't get a ridge. I chamfer the inside of a tube to allow easier pressing of the parts, but not because a ridge. Trimming the tube can make the parts the wrong length and then the parts won't fit correctly.
 
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