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Texas Turning

Member
Joined
Jan 30, 2018
Messages
42
Location
Texas
When I turn say for example a slimline pen and I take finished blanks off the mandrel the blank closest to head stock has tube and wood flaring out just a bit where tube meets bushing that separated the two blanks. I also noticed on some different kits after turning,wood was not flush with metal on pen kit . Any clues to the cause and how to fix it.

Thanks much!
 
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leehljp

Member Liaison
Joined
Feb 6, 2005
Messages
9,306
Location
Tunica, Mississippi,
The blanks are not being squared to the tube before (or after) turning. It is important that it is SQUARE. Some skilled and experienced people can eyeball it, but most people need "something" to square the blank to the tube on the ends.

An example is this at PSI:
https://www.pennstateind.com/store/PKTRIM7C.html
Or this:
https://www.pennstateind.com/store/PKSQUARE.html


Rick Herrell, a member here makes a sanding mill, an older version here:
www.penturners.org/forum/f167/sale-economy-sanding-mills-42098/

And I think this is the newer version:
www.penturners.org/forum/f50/thread-specs-commercially-available-nib-sections-153285/

These are different tools to square the blank, otherwise, un-squared blanks will cause the problems you described.

A bit of a warning, while many people have the carbide cutters for end squaring, they have a tendency to "bite" on occasion and cause other problems for many. Sanding it square with sanding mills are much better on the blank and safer in the long run. Experienced people can use a cutter OK, but inexperience can lead to more problems.
 
Last edited:

mark james

IAP Collection, Curator
Joined
Sep 6, 2012
Messages
12,707
Location
Medina, Ohio
In addition to all the excellent suggestions above - use calipers to measure your kit components, and turn to these specs. When you end up with a blank that does not match the kit, you needed to be more careful (no insult intended, been there, done that!).

I'll second sanding the ends rather than carbide milling.

And as MRDucks2 mentioned, the blank may turn during turning. I actually incorporate this into my process. On the off chance that the bushing may not be totally plumb, I will stop turning, release the tailstock, rotate the blank 1/4 turn, retighten, and continue. I'll do this several times. It does help if I am a slight bit "out-of-round."

Oh well, food for thought! Use as you will.
 

leehljp

Member Liaison
Joined
Feb 6, 2005
Messages
9,306
Location
Tunica, Mississippi,
The blanks are not being squared to the tube before (or after) turning. It is important that it is SQUARE. Some skilled and experienced people can eyeball it, but most people need "something" to square the blank to the tube on the ends.

An example is this at PSI:
https://www.pennstateind.com/store/PKTRIM7C.html
Or this:
https://www.pennstateind.com/store/PKSQUARE.html


Rick Herrell, a member here makes a sanding mill, an older version here:
www.penturners.org/forum/f167/sale-economy-sanding-mills-42098/

And I think this is the newer version:
CORRECTION BELOW (Sorry, I got multi-clipboard mixed up on the original link.)

These are different tools to square the blank, otherwise, un-squared blanks will cause the problems you described.

A bit of a warning, while many people have the carbide cutters for end squaring, they have a tendency to "bite" on occasion and cause other problems for many. Sanding it square with sanding mills are much better on the blank and safer in the long run. Experienced people can use a cutter OK, but inexperience can lead to more problems.

I PUT THE WRONG LINK for the 4th link.
Here is Rick's 2nd Link - Scroll WAY down to get to the sanding mills: www.penturners.org/forum/f349/custom-made-penturning-tools-accessories-92501/
 

More4dan

Member
Joined
Mar 17, 2016
Messages
2,102
Location
Katy, TX
You might also want to take a look at your bushings and make sure they are not causing the issue. There should be a sharp 90 deg angle between the part that goes into the tube and the transition to larger OD section. If it's rounded a bit, it could "flare" the tube when you tighten up the mandrill. It could also happen if you tighten it too tight or have it too loose that the blank spins on the bushings while cutting. There is no where for the brass to go other than "outward". This is more likely when turning between centers w/o bushings. Which I do often but rarely have this problem. I had to learn to find that sweet spot of not too tight or too loose, but just right.

Also, as others have noted, if the end isn't square then the brass tube won't fit flush against the bushing. The longer part of the brass tube will take all the force and flare outward.

Danny
 
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Texas Turning

Member
Joined
Jan 30, 2018
Messages
42
Location
Texas
Thank you very much! I do believe this is the problem not being squared. I thought just using the barrel trimmer would work. I want my pens to be excellent not just ok so I knew I couldn't continue to produce pens with this problem. I have a sanding mill on the way. I am also going to keep and eye on my bushings for wear and not over tighten. It really seems these could all be factors to this problem.



Thanks so much Ya'll,
 
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