Why Ebony?

[Doug Add]

One more shot of the White Owl. I probably should have kept this one.

 

[jwren]

I have persimmon trees on the farm. Over the years I have cut a few of these up and found a couple of things about them, one being that it is akin to sawing steel with a chainsaw and it has small voids in it. This could be from whatever killed it but seems to be a common trait. I have tried unsuccessfully to finish a piece or two over the years. Interesting colors, yellows and greens but not much visible grain structure. I thought about cutting down a healthy one but never could bring myself to do it as I really like the fruit and we do not have that many.

Thanks for sharing this, that's some interesting information. Don't have any near me, only get the fruit in the supermarket.

 

[2Dead]

Ebony feels great in hand and wears well. My first ebony. The first of many more.

 

[hunterjrg]

One more shot of the White Owl. I probably should have kept this one.

This is nice but with my preferred clip blade. Might search for one of these. A nice Sunday church knife.

 

[black mamba]

I like the striped stuff on fixed blades with larger handles like Big Mike showed, but the pure black on smaller folders.

 

[lambertiana]

jwren - Persimmon is the only North American representative of Diospyros.

While there are some species-dependent hardness variations, ebonies are all harder than rosewoods. Cocobolo (Dalbergia Retusa) has a janka hardness of 1136, while African Blackwood (Dalbergia Melanoxylon) has a janka hardness of 1720 and Brazilian Rosewood (Dalbergia Nigra) has a janka hardness of 1780. Gaboon ebony has a janka hardness of 3220, and Macassar ebony has a janka hardness of 3200. Obviously, there will be variation between individual trees in any species, but the trend is for the ebonies to be harder than the rosewoods, and not by a small margin.

For larger pieces I like Macassar ebony, and I have some Black & White ebony waiting for just the right application:

 

[Doug Add]

This is nice but with my preferred clip blade. Might search for one of these. A nice Sunday church knife.

If I had purchased the clip model I would probably still have it.

 

[glennbad]

Why ebony?

Cause it looks good, even on a TL-29 mod

 

[littleknife]

http://www.morlanwoodgifts.com/MM011.ASP?pageno=208

"Most wood/lumber/timber species will deviate in hardness but not by much more than plus or minus 10% of the chart numbers below from one piece of wood/lumber/timber to another or wood coming from two different geographical locations. With geographical locations there are exceptions. Examples would be,

Ebony Macassar Indonesian Grown {Diospyros celebica} 3220 - Specific Gravity 1.15
Ebony Macassar Australian Grown {Diospyros celebica} 3650 - Specific Gravity 1.296
Olivewood Mediterranean Grown {Olea europaea} 2740 - Specific Gravity .95
Olivewood Southeast African Grown {Olea europaea} 3180 - Specific Gravity 1.15

Also the wood/lumber/timber around knots, having interlocked grain, at less than 12% moisture content and burl wood will be harder than the chart numbers below which are of average side hardness with the wood at 12% moisture content."

From the following source:

http://www.wood-database.com/lumber-identification/hardwoods/african-blackwood/

"African Blackwood is considered to be among the hardest and densest of woods in the world; indeed, among some 285 species tested, (including Lignum Vitae), Gabriel Janka originally found African Blackwood to be the very hardest. Unfortunately, many online sources list African Blackwood’s Janka hardness at only ~1700lbf—which seems very unlikely given its confirmed specific gravity.”

and:

http://www.wood-database.com/lumber-identification/hardwoods/cocobolo/

"Also, there are a few misleading reports of Cocobolo’s Janka hardness being only about 1,100 lbf, and it’s modulus of elasticity at only about 1,100,000 lbf/in2: which is almost certainly either a typo or a different wood than what is commonly called Cocobolo (Dalbergia retusa). Reports indicate that Cocobolo is stronger and denser than Brazilian Rosewood, and that is the basis for the strength values (bending strength and modulus of elasticity) that are quoted at the top of this page.
Specific gravity is used to predict the hardness of wood with a fair degree of accuracy, and given its incredibly high density, (it sinks in water: see video below), Cocobolo’s hardness (and other strength properties) is most likely several times higher than the 1,100 lbf which is sometimes reported.”

A common problem with getting data for exotic woods is that the lumber trade frequently supplies several different species under the same trade name (sometimes belonging to completely different botanical groups). They can get away with it, because many times those woods do look quite similar.

 

[lambertiana]

Littleknife -

Until tonight, I had discounted those websites that list such high janka hardness numbers for those woods because they are not basing it on experimental data. In my experience (chemistry) there is sometimes a disagreement between theoretical and experimental data, and this pheneomenon is not limited to chemistry. So any time someone says that something is definitely true, based only on their theory, I take it with a grain of salt until I see actual experimental data to back it up.

I did not question the sources that showed a lower janka hardness for rosewoods because it went along with my own real world experience. I remember one time I was cutting blocks of wood into scales, and started with macassar ebony before moving to cocobolo. The difference between the two was night and day - after cutting the macassar ebony, the cocobolo felt like cutting butter with a hot knife. And my observations of antique slipjoints support this idea, too, because I usually see more wear/damage/denting in cocobolo handles than I do in ebony handles.

However, janka hardness is based on a specific test. It is the measurement of the pounds force required to push a 0.444" steel ball to half its diameter into the wood. I do not have a janka hardness tester, but I just did a home test that gave me qualitative data. I took a piece of cocobolo, a piece of african blackwood, and two different pieces of macassar ebony, and put all my weight on a medium sized phillips screwdriver to see which would dent more. To my surprise, I could observe a deeper indentation in the macassar ebony. Hmmm, much to digest here.

At any rate, any of these woods makes a good handle. All three have been used for a long time with good results.

If anyone has links to real janka tests of these woods, not numbers determined by theory from the density, I would love to see it.

 

[littleknife]

Lambertiana,

I don’t know how many of those numbers are based on true measurements.
I tried to search e.g. the USDA Forest Product Laboratory website, but could not find measurements for cocobolo.
What I found though that cocobolo in the lumber trade consists of at least 3 Dalbergia species (D. retusa including).

Cocobolo is frequently called Granadillo in some Latin American countries, but Granadillo could also mean a different wood, which resembles cocobolo:

http://www.exotichardwood.com/pic_granadillo.html


Anyway, you are right:

At any rate, any of these woods makes a good handle. All three have been used for a long time with good results.

:thumbup::thumbup:

Also, they look gorgeous. :thumbup:

 

[biglmbass]

Ebony still looks good when you see an older knife that has been through the wars ( in age-Literally ) and it carries the scars, you will see the fit and finish still spectacular to its Nickel Silver Bolster,.

It feels like velvet yet hard like steel. Something about Ebony,Nickle bolsters and carbon steel; Their hues compliment one another.

These guys say it better than I can. The fact that it's been used on knives for over 100 years also appeals to me.