Advice with cracks 5 mths later

Signed-In Members Don't See This Ad
mark james

mark james

IAP Collection, Curator
Joined
Sep 6, 2012
Messages
13,222
Location
Medina, Ohio
Hey Jeff -We need a Forum for "Pen First Aid"..:rolleyes:

Last October I turned 2 matching pens - gave one to Wifey and one to my brother.

This is wifey's pens - she's not complaining, she has about 40... she can match her clothing with a matching colored pen every day. :wink:

The wood was Figured Hawaiian Koa - Really nice chatoyance! And my turning was actually not bad. Finished with EEE and wax. (my skills with CA are just getting adequate).

I bought the wood directly from a vendor in Hawaii. So... the obvious is wood coming from Hawaii - to Ohio, then Ohio weather turning to -10 several times (very low humidity I assume). So my beautiful dry wood still went from high humidity to ultra low humidity... CRACK!!

I am open to suggestions. Yes, I can try to perfect CA finishing overnight and will try that if it's the best option. However - anything else? Wipe on Poly?

Thanks for the help.
 

Attachments

  • IMG_0322.jpg
    IMG_0322.jpg
    104.9 KB · Views: 367
  • IMG_0317.jpg
    IMG_0317.jpg
    93.5 KB · Views: 338
  • IMG_0319.jpg
    IMG_0319.jpg
    122.5 KB · Views: 457
  • IMG_0320.jpg
    IMG_0320.jpg
    141.4 KB · Views: 352
Signed-In Members Don't See This Ad
Do you know if the Koa was completely dried when you got it, and how long did you have it at your location before you turned it? Were you able to take moisture content (MC) readings, or weigh the blank over a period of time to check MC change?
 
SteveG said:
Do you know if the Koa was completely dried when you got it, and how long did you have it at your location before you turned it? Were you able to take moisture content (MC) readings, or weigh the blank over a period of time to check MC change?
Click to expand...

Sheesh Steve... I buy em, I turn em!

No to every question. The blanks looked fantastic when they arrived. I just looked up the invoice (won't mention the vendor because that's not what I do - the vendor delivered as ordered). I bought 6 blanks in Sept, 2012. I ordered them specifically for a close friend that was stationed in the Navy in Hawaii, and loved Koa. I turned 2 pens for him and his wife in November, 2012. I loved the shimmering so much I saved the remaining blanks for a higher end kit. The chatoyance was much more pronounced than High end Myrtlewood.

So, I had the blanks in Ohio for almost a year! Maybe my humidity theory was a little wet!!!

I still have the two remaining blanks and they look fantastic. :smile:

I understand your questions, but I have no desire to do moisture readings etc.
 
My best guess at the approach you should take (with zero experience at doing it myself) , would be to dis-assemble the cap , strip the wax/EEE finish off with acetone or something like Polyclens on a rag , fill the crack with thin CA , then refinish in the same way as the original finish , unless you want to strip the entire pen and refinish with CA .

Oh , your humidity theory is 100% correct .
 
For cracks that wide, I press in fine sanding dust to help fill the void. I would expect that if you filled it with just CA, it'll still show under the finish since CA is clear. Packing the crack with fine sanding dust makes the crack look like grain (especially if you use a species that will turn dark when hit with the CA…experiment on scrap first).

Ebony dust, for example, would make that crack dark. You can find woods that will stay light when hit with the CA which would make the crack stand out (which in this case likely is not what you want…just mentioning that as an option for future reference).

If the crack is wide enough, pack in some turquoise inlace for a thin vein of cool color. It's not a defect, it's a design challenge. :biggrin:
 
Could have been moisture...but seems like you would have noticed it while drilling, etc and if moisture I think it would have cracked sooner.

Was the pen let in the sun or on a heater or some other location where it was exposed to extremes of cold or heat? I find that cracks that appear later in time are normally due to this
 
I recently dealt with a deer antler crack. Sometimes it was very obvious and other times you couldn't see it. Turned out my son was leaving it where it got cold then took it into work where it was a lot warmer. Came to the conclusion it was expanding and contracting due to temp changes. Seems a little far fetched but I worked for a plastics plant and we had to dry plastic you would be surprised the amount of moisture it can suck up. Now I advise my pen accepters to be a where of there enviroment.
 
I just made a pizza cutter handle and when I installed the threaded insert a little while later I noticed a crack forming. I filled it the best I could with CA glue, and it stopped cracking farther, however you can visibly see the crack. I'm guessing my only option here is to just leave it alone, or strip it down and try and fill the crack with wood dust and CA glue. I bought the blank from Woodcraft, I didn't think of it at the time, but now after reading this thread, I'm guessing the blank was still wet and after turning it and the stress from putting that threaded insert in just caused it to crack. It was such a nice looking handle too ugg.
 
Could it have gotten cold, left in a car outside on a cold night or something. Wood and metal both shrink when cold and expand when warm, and they do both at a different rate. Put a wood pen in a freezer overnight then take it out and let it warm up the next day, it will often crack. The brass tube is expands at a faster rate than the wood.
 
I had a similar issue with a Burmese rosewood pen I did. It cracked after I gave it to someone, it was a ca finish and the pen sat in my house for about a month before leaving as a gift. The client asked me to fill it so I did with just ca and it looked ok to me but he was excited. He said the crack gave it a more "wood" look and feel, it was real feeling. He keeps it on his desk and uses it everyday, he is the president of his organization and shows it off all the time.
 
Last edited:
mark james said:
edstreet said:
See the post here on this topic ... http://www.penturners.org/forum/f14/do-jd-blanks-need-stabilized-117947/#post1612723

...
Click to expand...

I remember reading that when it was first posted. Thanks for the reminder. Makes more sense now!

I guess I have to figure out if my crack is active or passive... Hmmmm. I see a future with CA in my crack... :bananen_smilies008:

Better stop now!

Thanks Ed.
Click to expand...



I would guess that an active crack in the case here would be very hard pressed as more often than not the blank thickness is very minimal. However depending on the pen used it could be paper thin (sierra or slimline) to something very thick (panache, euro). Going out on a limb I would have to guess (educated gustimate mind you) that most in this case would be passive.

A good hard solid drop or bang could cause cracks like that to happen, also sudden shock. One case that I have seen is chemicals etc get trapped in the blank and sets up a very weak area and causes the wood to rot over time. I have seen one pen go from very solid to mush in about 4 months time period.
 
Chasper said:
Could it have gotten cold, left in a car outside on a cold night or something. Wood and metal both shrink when cold and expand when warm, and they do both at a different rate. Put a wood pen in a freezer overnight then take it out and let it warm up the next day, it will often crack. The brass tube is expands at a faster rate than the wood.
Click to expand...

Well the only time it was somewhat cold would have been walking from the store to the truck, then from the truck to the house. Everything else is room temperature, house, my shed where I do my lathe work, and the store as well. My only guess would be it is wet at this point.
 
Not sure would do anything to those pens now. Probably require complete disassembly to clean off remaining EEE & wax.

Cure might be worse than current problem!

EEE, needs to a top coat of film finish or oil varnish applied over it. What you are seeing is fade back of sheen. Think would have same result if applied oil varnish blend over the EEE.

Koa can be sanded & polished to a natural sheen. Koa will accept any film or oil-varnish blend finish without need for EEE. Film finishes little better at slowing down water vapor transfer. I include CA as a film finish because will get a build with more coats added.
 
Yesterday I went looking for the pen which I took back to the shop to try and fix ...

Wifey had already taken it back to work - she said she hadn't even noticed the cracks. Then she says, "Oh, Its too nice to keep out on my lab bench (Polymer Chemist), so I hide it in my sealed low humidity hood.....

Ah yes... :rolleyes: Maybe I'll make you a nice trustone pen!
 
You must log in or register to reply here.
Back
Top Bottom