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RockandCole 01-04-2017 05:34 PM

OK, so what happened here?
 
1 Attachment(s)
This beautiful burly piece of olive wood had me drooling all through the turning, and looked great throughout sanding, and then when I stop my lathe from buffing it, this was staring at me. What did I do? (Seriously, I'd like to avoid this in the future if possible, it was such a beautiful piece)

RBcarving 01-04-2017 05:39 PM

Most common would be a little glue left inside the tube...then when pressed onto the bushing & turned thin, it cracked. An easy "fix" though...you can fill the gap with some CA and then strategically place the pocket clip over the crack during assembly...you will never see it.

Skie_M 01-04-2017 05:44 PM

First, take it off the bushings ...

Second, clean the glue out from inside the barrel ...

Apply some thin CA to the crack, work it into the gap and hopefully the crack will disappear.

Third, put the barrel back on the bushings, and then sand/finish again to give the smooth appearance you desire.

If the crack is still visible, hopefully you can hide this under the clip ... but if you've differentiated the upper and lower barrels and this is the lower, you may have to cut/turn off this damaged part and apply an "oops band" or possibly live with the defect. It may also be possible to just fill it in and pray it's hardly noticeable.

JimB 01-04-2017 05:50 PM

I agree with the above about why it cracked. You can also fill the crack with something and adding thin ca. When I have cracks in bowls I use coffee grounds, rubbing them into the crack, then putting a small amount of thin CA. The dark coffee often just looks like it is part of the wood. People do not even notice it unless I point it out to them.

duncsuss 01-04-2017 06:21 PM

Quote:

Originally Posted by JimB (Post 1894152)
You can also fill the crack with something and adding thin ca. When I have cracks in bowls I use coffee grounds, rubbing them into the crack, then putting a small amount of thin CA.

Alternatively, sometimes you get better "camouflage" by putting a drop of thin or medium CA on it and sanding with ~220 grit so the sanding dust gets caught and glued in the crack.

(Keep the sandpaper moving so it doesn't get glued to the barrel.)

jttheclockman 01-04-2017 08:52 PM

You got the answers as to how to fix it. As to the why, my guess is it was not properly trimmed to the tube and then too much pressure was exerted on the bushings. Now add the heat from sanding on a thin piece of wood and all kinds of bad things could happen. Or it was cracked from using a barrel trimmer and when finally turned down the crack appeared. To avoid this you may want to start sanding the ends down instead of a barrel trimmer. I am going out on the limb here because you are a new turner and we do not know if you are aware of these things and exactly what your method of preparing the blank and turning the blank are. So we are at a disadvantage. We can only make suggestions and it is up to you to try to find the problem on your own. Do a few of these and things become clearer as to what to look for.

This same problem can appear when assembling the pen also and if the CA does not hold it will appear. Good luck.

RockandCole 01-04-2017 09:07 PM

Thanks for the suggestions. I was using a carnauba finish on it (not the most popular from pens from what I gather, probably a new thread as to why? in the future...) I took it off while still warm and let it sit in my workshop (unheated garage in Wisconsin) and as the wax cured and hardened the crack seems to have almost disappeared, I'm going to attempt to rebuff it tomorrow and see if the wax has sealed it. I've been using the barrel trimmer but I don't like it, I didn't realize sanding it was an option, I'm assuming a 6" disc sander would do the trick?

jleiwig 01-04-2017 09:12 PM

How hot did you get it? Heat could have caused it to crack as well. Less common, but it could be a possibility.

RockandCole 01-04-2017 09:18 PM

Quote:

Originally Posted by jleiwig (Post 1894219)
How hot did you get it? Heat could have caused it to crack as well. Less common, but it could be a possibility.

I'm not sure, I run the lathe at 2500 or so to apply the wax and then keep it there and pinch with a cotton towel to melt the wax into the wood. I do this 15-20 times in a row to really build up a heavy and hard finish. (Variation of a Technique I carried over from tobacco pipe carving and finishing)

Edgar 01-04-2017 09:27 PM

A 6" disk sander will work fine, you just need a jig to present the tubed blank perpendicular to the disk. A set of inexpensive transfer punches from Harbor Freight is handy because you want to use a bar, rod or punch that is as close to the I.D. of the tube as possible for a nice, square trim.

Some turn a round wooden disk to mount on the lathe headstock & apply a piece of adhesive sandpaper to it then put a punch in a chuck or holder of some sort in the tail stock.

I use a sanding disk intended for a hand-held drill mounted in a Jacob's chuck in my head stock.

There are a number of ways to approach it and there's been lots of discussion & photos here over the years. I'm just on my iPhone right now or I'd post some links for you, but you should be able to find some of them if you use the Search function.


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