crazy cracking wood

[Adillo303]

I bought some ebony and some pink ivory from West Penn Hardwoods. I cannot seem to mske anything from them.

I made a Princeton from both woods. Turned fine sanded fine then when I put the CA finish on, all went well till I wet sanded. Chunks of the CA just peeled off.

Wiped down with DNA first, 2 coats thin 8 coats med. Sealed the end grain.

Then tried a pair of stylus pens. The wood cracked on both pens when pressing the transmission.

Is there something about these woods I am missing?

 

[1080Wayne]

Yes , a lot . Two of the most problematic woods , for several reasons . Very hard and dense , which translates into extremely slow drying and acclimation to your ambient conditions , very `brittle`or low ability to withstand the `stretching `required when a part is forced into the tube , as you found out , and a pronounced tendency to crack weeks/months/years after completion . Apart from that , beautiful woods .

 

[1080Wayne]

But , if you insist on using them , what I do is the following (in a much dryer climate than yours , and none of this is guaranteed to work , but deviate at your peril !!)

1) Drill slowly , clearing the bit every 1/8 inch
2) Drill with with WATER in the hole .
3) Do NOT let the wood get more than lukewarm to the touch when sanding .
4) Oversize the tube ID with a rat tail file BEFORE pressing in parts , The parts should slide in easily by hand . Glue them in .

 

[PenPal]

Andy,

I have had great success with both timbers however I leant early on to be infinitely careful choosing suppliers of Ebony and Pink Ivory. I believe as well that Sth American Snakewood is even worse.

My answer to Ebony is to use African Blackwood instead also be carefull where you buy it from Africa they often polish it with boot polish so the intense black may be brownish or flecked underneath the polish.

From America I have even bought figured Pink Ivory Wood used it with 100% success so once again trustworthy sources mine was from Kentucky importer. All names escape me now of suppliers I used cause I like variety in my pens as well.

When I glue the blanks I use an elastic glue such as Gorilla Poly that foams with clearance holes in the timber and carefully ream the tubes before pressing parts unlike others I abhor water in my drill press or lathe.

Some times with a block of Ebony splits appear when cutting even this is bad kama as well.

Trust your success rate improves mine has to where now its rare to lose a pen to splitting.

Kind regards Peter.

 

[Adillo303]

Thank you both.

I was brginning to feel that I was loosing my touch. I too don't often loose a blank.

The ebony pen I made is gorgeous. I wish I liked that style of pen, I would gladly carry it. I am disappointed in the pink ivory. Lighter paduak looks nearly the same with better success.

Well, I'm off to make a couple sleds so I can try scallops. Thank you both again.

 

[Adillo303]

OK next question, I finished the ebony one with Beall Buff, then friction polish with a light overcoat of Caranuba. Therefore no CA. I would not sell the pen, but, it looks really nice.

Would anyone have a suggestion as to how to mitigate the crack.

Thank you

Andy

 

[randyrls]

Would anyone have a suggestion as to how to mitigate the crack.

Andy; This happens with Corian and some acrylics too! Two things come to mind.
1. Make sure to deburr the ends of the brass tube before pressing in the fittings.

2. Before gluing in the brass tubes, insert a transfer punch about 1/4" into the end of the bare tube. Twist it in a circle to expand the brass tube until the fittings are a slip fit. Now glue, assemble, and turn as normal. Use either loctite or Epoxy to glue in the fittings. To prevent squeeze out on the fitting, put a small dab on the inside of the tube. Insert the fitting with a twisting motion. Clamp lightly if needed.

 

[1080Wayne]

I would have sealed the crack by applying a small drop of thin CA at the crack with the barrel standing on end (and then kept all appropriate body parts crossed , hoping not too much ran where I didn`t want it ) . If the crack is straight along the barrel , it is also possible to build a small dam around it , fill it with thin CA , wait until it cures , then refinish .

However , the carnauba wax may prevent these approaches from working .

Randy`s advice above is good .