Question about Snakewood

[penturner84]

First of all sorry about the large pictures on my first post. I wasn't thinking.

 

My question is about drilling Snakewood. I made a Father Sing pen and pencil set for a friend of mine with this wood and had no trouble but am having problems drilling the hole for the tubes on a Jr Statesman. They crack before I can get the hole drilled.

 

The tubes for the Father Sing is 7mm and the tubes for the Jr Statesman are 12.5mm and 27/64".

 

I'm wondering if the larger diameter hole is what is causing the problem, and if it is, is there any tricks anyone can tell me about?

 

BTW the pens I posted before are all Jr Statesman's, all turned on a Jet mini lathe. The woods are Tiger Maple, Curly Koa, and Texas Ebony.

 

Thanks for any help,

James

 

 

[Radman]

Hi James,

 

Snakewood is very well known for its cracking abilities. If you made pens for a friend as you mentioned, in snakewood....more than likely...they'll crack .

 

Don't mean to be the bearer of bad news, but that's the nature of that wood. Not all cracks, but it seems the majority does. I'm not sure of the reason, but have heard that it may be due to heat buildup during the turning process. I've got a snakewood blank in my shop. Had it for a few years. Some folks have tried different things to help avoid cracking. Maybe someone here will share their experiences :bonk:

 

I've not turned any, because of the most likely cracking.

[Ruaidhri]

First of all sorry about the large pictures on my first post. I wasn't thinking.

 

My question is about drilling Snakewood. I made a Father Sing pen and pencil set for a friend of mine with this wood and had no trouble but am having problems drilling the hole for the tubes on a Jr Statesman. They crack before I can get the hole drilled.

 

The tubes for the Father Sing is 7mm and the tubes for the Jr Statesman are 12.5mm and 27/64".

 

I'm wondering if the larger diameter hole is what is causing the problem, and if it is, is there any tricks anyone can tell me about?

 

BTW the pens I posted before are all Jr Statesman's, all turned on a Jet mini lathe. The woods are Tiger Maple, Curly Koa, and Texas Ebony.

 

Thanks for any help,

James

 

James,

 

No prob about the pictures - it is not a hanging offence

 

One of the problems with many of the exotics is that they often come only part-seasoned.

Depending on the remaining moisture level the heat from drilling can cause expansion & cracking.

• Try making sure you are using a really sharp drill bit
• Make sure your speed is suitable.
• Drill a little at a time, allowing the wood to keep cool (sometimes having a few bits and using them in succession can help).
• You may also find that drilling a pilot hole first (say around 2-3 mm) makes it easier.

You can also dry the wood further in a microwave, but that's another day's discussion

 

Regards,

Ruaidhrí

 

BTW - I presume you are using exotics from a sustainable source

 

 

[penturner84]

I'm getting the wood from Bell Forest http://www.bellforestproducts.com/ who I have had very good luck with on all the other woods I have have bought.

 

I checked one of the blanks and it was less than 10% moisture content.

 

I didn't think about the bit being dull. I am trying to drill a little bit at a time at 500 rpm, thats as slow as my lathe goes.

 

Good idea on the pilot hole, I'll try that.

 

I thought about wrapping the blank with wire to serve as a heat sink. Do you think that might help.

 

James

Edited September 2, 2007 by penturner84

[richardandtracy]

I thought about wrapping the blank with wire to serve as a heat sink. Do you think that might help.

James,

 

I've not used that timber, but if it is as insulating as other exotic hardwoods, then I very much doubt that wire will act as an adequate heat sink. You could try a variation on the pilot hole idea - start with a pilot hole and work up the size in as small increments as you can manage, say 0.5mm.

 

Ideally you'd flood the work with coolant at the same time...

 

Regards

 

Richard.

 

[jgourlay]

This'll make the making a nasty experience, but it has worked for me. Take a very thin, long set epoxy such as "West System 3" and put than and the two blanks in bag. Refrigerate overnight (slows it down), but not so long that you mummify it in the epoxy.

 

Generally, this has given me enough soak of epoxy into the blank that I can drill it with new, sharp, brad point bit (I like the Lee Valley bits).

 

If you really have a problem blank that you are just desperate to use because of the beauty, you can take this a step further. Use a ziploc+rubber band to seal the end of a toilet paper tube, set your blank on the bottom in the middle, and make an epoxied tube with the blank in the middle. Don't try and get that out of the roll, just drill your holes, then turn off the roll and the epoxy.

 

I know it sounds like the anathema of everything you stand for by turning pens by hand, but sometimes you just have to do what you have to do. This works well for punky and spalted wood too.

 

I can't emphasize enough: sharp bit. Also, many who come to pen turning via the path of bowl/spindle turning don't learn the correct way to drill a hole on the lathe: chuck your work, and leave the bit in the tail stock. This means the drill does not rotate. So you can sneak the flexible plastic tube of canned air along the flute into the hole and get some serious cooling action in there--very good for olive wood blanks.

 

Also, use your feed/speed chart. IRC, your speed should be 500 rpm for a 7mm brad point in hardwood. Light pressure on the tailstock.

[penturner84]

jgourlay thanks for the reply. It sounds like good advice. I will try that on my remaining blank.

[Eagle]

jgourlay thanks for the reply. It sounds like good advice. I will try that on my remaining blank.

 

I drill a lot of intricate glue ups on my Jet mini woth no problems.

I am guessing you are using a collet chuck of some type.

What I do for my glue ups is to turn the blank between centers to approximately.70.

I put a thin coat of CA on the blank and then a coat of thick.

I then wrap with gauze(only one or two thicknesses).

Drizzle thin CA on this and let harden for a couple of hours.

The CA acts with the gauze to make a hrd sleeve around the blank.

Turn or sand down to a uniform diameter under.75 for the collet.

My theory is that if the material has no where to move to if it wanted to "blow out" , it cannot because the "cast" reinforces it.

I have taken all my brad point bits and converted them to split points with a Drill Dr.

They drill faster, truer and do not split the wood.(ever notice the makers of diamond wood reccomend to NOT use brad points on their product?It is hard and dense just like snakewood,using a brad point is asking for trouble

If you do not have a Drill Dr, get one.

No need to buy overpriced bits from suppliers,I use the 115 piece set from Harbor Freight.

This set goes up to 1/2" but larger bits can often be found at flea markets(bring your calipers and magnifying glass)

 

Snake wood comes from a dry arid region,I have a friend who acclimates it in his shop for 6 months before he will work it.

[penturner84]

Eagle, I have the 115 pc set from Enco but I'd bet they are very similar. Thanks for the advice on the drill Dr. That sounds like a worth while addition for drilling.

 

James