Polishing the cap thread tenon

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Hoping I have the terminology right, but, any suggestions or tips on how to finish/polish this bit?
Cap thread tenon.jpg
 
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hooked

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I have been polishing that tenon before threading. I also find using canola oil to lubricate while threading helps achieve the polished look of the threads better than other lubricants I have tried.

Once threaded, I use waxed fly-tying thread ( sewing thread and dental floss also work), put a little plastic polish on it, and run it through the threads manually several times to gently polish the threads as much as possible.
 

its_virgil

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I use Magic Juice polishing compound from Stadium Pen Blanks on the threads then screw the cap on and off several times. Seems to work for me. Then clean the threads. I too polish the tenon prior to threading. I suppose any good polishing compound will work.
Do a good turn daily!
Don
 
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I appreciate your responses, but, am struggling to visualize this. If you polish the tenon first, dont you cut off the polished bits when you thread and put in the thread relief? I think I'm not connecting some dots properly. :)
 

CjG78

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Judging by the look of that threaded material it is quite coarse. Turn your tenon with a razor sharp parting tool, to a touch larger than you need, then I use 1000 grit micro mesh with mineral oil to size. Then cut tenon with lots of mineral oil. Once polishing pen, I like to gently apply mirka polarshine on the tenon and remove with a toothbrush gently on high speed. Tenons will never be as glossy as the barrel, but this method gets them pretty good. Be careful not to press to hard as the threads can quickly go pear shaped
 

jalbert

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I appreciate your responses, but, am struggling to visualize this. If you polish the tenon first, dont you cut off the polished bits when you thread and put in the thread relief? I think I'm not connecting some dots properly. :)
You don't need a thread relief, so if you forego that then you don't have to worry about having created an area that's difficult to polish
 
Joined
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Location
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Judging by the look of that threaded material it is quite coarse. Turn your tenon with a razor sharp parting tool, to a touch larger than you need, then I use 1000 grit micro mesh with mineral oil to size. Then cut tenon with lots of mineral oil. Once polishing pen, I like to gently apply mirka polarshine on the tenon and remove with a toothbrush gently on high speed. Tenons will never be as glossy as the barrel, but this method gets them pretty good. Be careful not to press to hard as the threads can quickly go pear shaped
Which number Mirka compound do you use?
 

anthonyd

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Shawn Newton has a video and some pictures of a horsehair brush attached to a rotary tool on his Instagram site. He uses some plastic polish on the threads and rotates the pen body on the horsehair brush. He cautions not to use the wheels with plastic bristles. He says he gets the brushes inexpensively on e-bay.
1681352301730.png
 

PatrickR

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i assume you are talking about the flats you have cut fore and aft of the threads. Personally I find them odd looking and unnecessary. As to polishing the actual threads, I don't find it necessary. If the tenon is sized correctly, the die is sharp, well lubed and you don't rush they should be good to go. I do use sewing thread to clean and smooth the valley.
 

duncsuss

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As others have siad, polish the tenon before threading.

What they haven't said is to avoid making the tenon too large a diameter - I make flats at the peaks of the threads, never sharp points. Meaning, there will be polished surfaces that are not cut in the process of threading. IMO it looks much better.

For example - if I'm making the cap using M13x0.8 threads, I'll size the tenon to 12.8mm and polish it. There's still plenty of grip (minor diameter of the female threads in the cap will be about 12.2mm, so I have 0.6mm grip out of a potential maximum of 0.8mm.
 

its_virgil

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I appreciate your responses, but, am struggling to visualize this. If you polish the tenon first, dont you cut off the polished bits when you thread and put in the thread relief? I think I'm not connecting some dots properly. :)
Cutting the threads with a die seems to go easier and smoother when I polish the tenon than when I don't. It possibly could just be me and totally not necessary but I will continue tenon polishing prior to cutting the threads.
Do a good turn daily!
Don
 
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