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Old 12-31-2009, 06:20 PM   #11 (permalink)
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I don't "think" that it is what I am about to suggest but there are the possibilities:

Storage in widely varying temp ranges over a 24 hour period causes ebonies and snakewood to crack. Tubes expand and contract at a different rate that wood or PR/acrylic. IMO that this does not affect each other unless too tightly fit. (Temp range dramatic, too tight a fit to allow for expansion / contraction.)

There was no direct sunlight on the pen, or pouch (with pen inside) coming through a window for an hour or so, was there? That will do it.
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Old 12-31-2009, 07:02 PM   #12 (permalink)
 
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Toby, I am very interested in this. The cracks that you show seem to be radial, not longitudinal? All on one side, and continuing to progress?

I would like to get as much information as possible to help find cause. If it is the resin, I need to know so that I can make it right!! If anyone else is experiencing the same problem, please PM me or post here.
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Old 12-31-2009, 07:26 PM   #13 (permalink)
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I have never seen cracks like those and the fact they are continuing is odd.
I have done every scenerio mentioned. I have left pens and blanks both in the sun for hours at a time, I have used extreme pressure to get parts fit together, I have done as Skippy and heated blanks for various reasons, I've purposely created heat with sanding/cutting (which only caused the adhesion between the tube and blank to let go, nothing more), I've dropped pens and blanks purposely, I've left pens in my shop and in vehicles in varying temperature changes, and any other things people post they have problems with and I've never had a blank crack in any way.

I would like to see how this plays out.
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Old 12-31-2009, 07:33 PM   #14 (permalink)
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I think the blank is a micro amount too long maybe? If that is the case, when you press the parts, the part would sit against the PR instead of the end of the tube. If you use a tiny bit too much pressure, you crack the blank. It takes a while for the cracks to show up because the subtle changes in temp cause the PR to expand and contract ever so slightly, pushing the parts out a micro amount and exposing cracks.

Explains how they got there, Explains the direction, and nature of the cracks, Explains why they took so long to show, and explains why they keep showing up. Just my thoughts, but it could be tested i guess.


It will be interesting to follow and see the final conclusion! I am intrigued for sure.
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Old 12-31-2009, 07:42 PM   #15 (permalink)
 
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Quote:
Originally Posted by RAdams View Post
I think the blank is a micro amount too long maybe? If that is the case, when you press the parts, the part would sit against the PR instead of the end of the tube. If you use a tiny bit too much pressure, you crack the blank. It takes a while for the cracks to show up because the subtle changes in temp cause the PR to expand and contract ever so slightly, pushing the parts out a micro amount and exposing cracks.

Explains how they got there, Explains the direction, and nature of the cracks, Explains why they took so long to show, and explains why they keep showing up. Just my thoughts, but it could be tested i guess.


It will be interesting to follow and see the final conclusion! I am intrigued for sure.
Just adding a thought here not trying to contradict you. I would buy into a bit more if it were a crack or two. The first crack or two would relieve the stress from the pevious scenario, I would not think there would still be enough stress to continue the cracking on down the blank that many times. Again, just another thought. If anyone has any more of those particular blanks to put through some testing might be the only way to get any answers, and then maybe not.
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Old 12-31-2009, 07:56 PM   #16 (permalink)
 
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Maybe the woodshop gremlins are coming in at night and bending your pen!

Seriously, that is the first I have seen like that. It seems very odd.
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Old 12-31-2009, 08:22 PM   #17 (permalink)
 
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Quote:
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<snip> If anyone has any more of those particular blanks to put through some testing might be the only way to get any answers, and then maybe not.
Just to add more data...

I have 2 of the Golden Dawn blanks (purchased separately in July and August), turned a JGII out of one in mid-November and no cracks to date. I've made 30+ pens using Dawn's PR blanks and the only problems I've had with cracking were me drilling too fast (but I knew it right away -- never had a crack develop after completing the pen).
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Old 12-31-2009, 08:50 PM   #18 (permalink)
 
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Quote:
Originally Posted by PR_Princess View Post
Toby, I am very interested in this. The cracks that you show seem to be radial, not longitudinal? All on one side, and continuing to progress?

I would like to get as much information as possible to help find cause. If it is the resin, I need to know so that I can make it right!! If anyone else is experiencing the same problem, please PM me or post here.
Hi, Dawn...they are indeed radial, rather than longitudinal. They are only on one side, and on one of the two halves of the pen I turned. I am not of the opinion that it's a failure of your product, but I probably don't have enough experience in these matters to be credible.

I'm going to try disassembling the pen this weekend. If you like I can send them to you for additional analysis.

Regards,

t.
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Old 12-31-2009, 09:16 PM   #19 (permalink)
 
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Please don't disasemble the pen until you are convinced that the cracking has stopped.
Thank you. Sorry for your trouble.
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Old 12-31-2009, 09:18 PM   #20 (permalink)
 
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Obama did it.
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