Fixing Chipout In A Blank

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crokett

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Dec 4, 2012
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I cast a blank using Silmar 41, some PearlEx Carbon Black and embedded brass swarf. I want to use it for an Apollo semi-kitless from Bullseye Turning. I drilled everuything out, glued in the pieces and got them nearly turned down. The cap section has a major chipout in it - maybe 3/32" deep. I think it is where swarf didn't have enough material around it. A normal pen I'd probably cut my losses and just get a new tube. This one I want to try to fix. I tried epoxy with some of the carbon black, but it dried sort of rubbery and didn't look the same as the polycrilic. At this point Im thinking of casting more carbon black over the whole thing in a vertical mold and turning back down to size, or casting clear. If I were to cast clear over it, would the chipout be visible through the clear coat? Would CA glue plus the carbon black work? I'm worried about the different materials having a different finish when it is polished out.
 
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magpens

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In my opinion, if you cast clear over the chipout there is no guarantee the chipout will not be at least partially visible.

You call it a "major" chipout, and you estimate the depth as 3/32" . . . almost surely that will remain visible, sorry to say.
 

crokett

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I decided I am going to attempt to turn the damaged casting off the parts and start over. The nib side is brass, that should not be that difficult. The side that goes into the cap is plastic, that will be slightly more difficult. I may also turn the cap section down to something close to gone, and then use a larger drill bit to accommodate it in a new blank.
 

KenB259

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I decided I am going to attempt to turn the damaged casting off the parts and start over. The nib side is brass, that should not be that difficult. The side that goes into the cap is plastic, that will be slightly more difficult. I may also turn the cap section down to something close to gone, and then use a larger drill bit to accommodate it in a new blank.
I fear having to do the same at some point in the future and am anticipating that plastic piece being an issue. I contacted Kate at Bullseye last week to see if replacement parts were available and she told me that is one thing she is working on. So it sounds like at some point we'll be able to just buy that plastic insert.
 

crokett

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Last resort will be to turn the casting off the nib side then figure out what diameter and thread pitch I need and drill and tap a solid blank for the cap. Then it will become a mostly-kitless instead of a semi-kitless :)
 

crokett

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Dec 4, 2012
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Mebane, North Carolina
I fear having to do the same at some point in the future and am anticipating that plastic piece being an issue. I contacted Kate at Bullseye last week to see if replacement parts were available and she told me that is one thing she is working on. So it sounds like at some point we'll be able to just buy that plastic insert.
I was able to turn the banks odd both of the inserts. I did the brass body first and then the cap. One thing I don’t like is the small shoulder on the insert for the nib. I’m going to counterbore the body blank so that shoulder is flush in the end of the blank. The cap will screw on without a gap if I do that
 
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