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I've gotten ahold of some karri (Eucalyptus diversicolor) stock that is about 4" in width.  It was salvaged from some old railroad ties in Australia.  It's a unique wood with an attractive grain pattern and a deep reddish-brown color, but it's also very splintery - something akin to wenge.

I originally though the karri might be similar to jarrah, which is a common fingerboard wood, because they are closely related species.  I have enough stock to make several fingerboards and a couple of complete necks, but I'm concerned about the splinters.  The stuff planes without too much chatter but has a pretty open grain.  It's never really smooth, and it still tends to splinter at the corners.  Could it be sealed, or should I just avoid it for fingerboards?

-Ben

I'd epoxy seal it.

West System epoxy?

So here's a related (dumb) question:

Say I want to send the fingerboard wood to someone else for radiusing and slotting.  What's the best way to keep epoxy out of the fret slots after the fact?

Thanks,

-Ben

Karri is quite splintery, and it is very straighted making it great for bridge stringers or pylons, it can hold MASSIVE weight. Could not see it in contact with the ground used as railway sleepers though, the white ants love the stuff and it would be gone real quick. Are you sure it is not Jarrah?? Pretty hard to pick the two apart and Jarrah certainly was pretty much THE standard for railway sleepers all over a good deal of AU.

Cheers

Kim

EDIT, "Very straight grained" don't know what happened there??

[QUOTE=larkim]Are you sure it is not Jarrah??[/QUOTE]

Not really.  I've never seen Jarrah in the flesh, but in photos it appears more chocolate in color rather than ruddy like this wood is.  The grain is... odd.  It looks a bit like bear fur.  There is a transverse weave to it so that planing in either direction gives about the same amount of tearout.  There are some pitch pockets.  I'll try to get a photo up later.

I sourced the stuff quite a few years ago from Shiver Me Timbers - a wood recycler in Victoria.  I only have their word to go on.

-Ben

[QUOTE=Ben Furman]
I've never seen Jarrah in the flesh, but in photos it appears more chocolate in color rather than ruddy like this wood is.  The grain is... odd.  It looks a bit like bear fur.  There is a transverse weave to it so that planing in either direction gives about the same amount of tearout.  There are some pitch pockets.  I'll try to get a photo up later.I sourced the stuff quite a few years ago from Shiver Me Timbers - a wood recycler in Victoria.  I only have their word to go on.-Ben[/QUOTE]

Ben,

I cannot realy comment on the transverse grain other than to say that unless the board is highly figured, both Jarrah and Karri normally plane OK with a good sharp shallow set blade. However Karri is generally more "fury" than Jarrah when rough sawn and it is also more splintery as well, but both plane up smooth enough. As mentioned above, if this stuff was ex-rail sleepers I would doubt very much that it is Karri as you just don't leave it on the ground.

Maybe after I see a photo I can help more but man, you need to know that we have a HEAP of different hardwoods out here so there is no guarantee of any real accuracy. I can confirm that both Jarrah and Karri come from Western Australia which is on the other side of the continent to the vendor you got this stuff from in Victoria, but once again, this is no big clue as Jarrah sleepers were used all over, even as a substrate beneath the cobbled roads of London.

As far as the colour goes I would not read too much into that and to see my point I think you need to have a look HERE at the post I done on this very topic some while back.

Cheers

Kim

[QUOTE=Ben Furman] West System epoxy?So here's a related (dumb) question:Say I want to send the fingerboard wood to someone else for radiusing and slotting. What's the best way to keep epoxy out of the fret slots after the fact?Thanks,-Ben
[/QUOTE]

A technique that some people use for keeping glue out of the slots while gluing binding onto fretboards is to cut strips of a plastic material (such as cut up coffee can lids) and insert them into the slots. Maybe this would work for what you're thinking about doing.

Now, you didn't ask my opinion on this, but radiusing a FB, with careful use of a handplane, sanding blocks, and some radius gauges, is not that difficult. And slotting a FB, if you have a tablesaw with a fret slotting blade and make a simple sled/jig that uses a fret slotting template, is a piece of cake. Just a little encouragement for you to go ahead and do these things yourself...

_________________
Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Kim - Thanks for the link to the other thread.  That block figure is indicative of the kind of grain weave I'm talking about, so apparently it happens in jarrah too.  Here is a photo of a roughly planed karri board in the south Texas sun:



(Click on the thumbnail to enlarge it in a new window).  It doesn't really resemble the jarrah photos to my eye, although there are clearly some similarities in color, etc.

Todd - Thanks for the encouragement!  I will eventually need to learn fingerboard planing, but it's low on my list of priorities given that companies like our sponsors can do it so reasonably.  I haven't even carved and fretted my own neck yet, so I have a long way to go.  (I took Rick Turners comments on the "rice" thread quite seriously.)  As for the neck carving, I'm thinking I'll start out with some good ole American Prunus serotina....

-Ben

Is this stuff chemical free? I know here they chemically treated old railroad ties. Just wondering if it would be safe to use. Old rail ties are treated with a chemical that contains arsenic.

_________________
Guitars, guitars and more guitars.

Looks like it's really got some interlocking grain. As Kim said, it's pretty hard to say for certain what type of wood it is. I have some Red Gum and Cooktown Iron Wood that look fairly similar to your sample depending on how recently they were machined. Both are very hard and splintery.

I've tried making some fret boards out of both with my radius jig and a router. Some times it works, and other times the pieces shatter like glass. Even using a countersink bit for bridge pins has destroyed a piece. If I were to try using it again I would only shape it with hand tools and sanders. That said, your not going to find many woods that are harder than some of these Aussie ones.

_________________
Allen R. McFarlen
Barron River Guitars & Ukuleles
Facebook
Cairns, Australia

Wow, I sure hope it wasn't treated.  The wood is pretty rot resistant on its own, but then there is the insect damage that Kim mentioned....

I can only hope that the species is really karri.  Karri is stiffer per unit density than any other hardwood, which is why I decided to try it.  I should have guessed that it would be difficult to work, so now all that remains is to try it and use the epoxy sealer for good measure.

Thanks,

-Ben

I half remember reading somewhere that the only sure way of telling the difference between karri and jarrah is to burn a splinter of each. The jarrah will produce black ash while the karri will produce a white ash.

Hope I got that right. Does that ring a bell with you Kim?

Paul,

Maybe you read "The bushman's test to distinguish between the two is to burn a splinter; if it leaves a white ash it is Karri, if it is black or grey it is Jarrah." HERE?

Anyhow, yes I have heard this before around the traps to, but Jarrah feels and smells like Jarrah, and if you work with it a lot you can generally tell when you pick it up in your hands.

Dark Jarrah is unmistakable, it is so rich in chocolate plum colours where as Karri stops at the edge of dark brown. Also the darker Jarrah gets the stronger it smells and the more it will weigh. So what Ben is describing does seem to be more in line with Karri as Karri can be a bugger to work at times and has a tendency to be more fibrous or splintery, but as mentioned above, it all works OK with well tunes tools.

As for the image, it is realy hard to tell, especially as there is nothing showing any perspective of how close to the wood the image was taken. I will say that the pores look very large for either Jarrah or Karri but the interlocking grain is not exclusive to either. If I had to pick between the two, I would lean toward Karri but as said, no guarantee. I reckon that Ben should burn us a splinter and report back.

Cheers

Kim

Sorry for the lack of a reference in the photo.  The board is 100 mm wide.

I burned a splinter... but then I felt a bit silly.  The ash is white, but isn't all wood ash white if it burns completely?  Black char... white ash.

-Ben

Ben,

I downloaded the image to my editor and had a look at it in a resolution matching that of a 100mm board, the pores are consistent with those displayed buy either jarrah of karri. The colour is a match with either dark karri or mid jarrah. Don't know too much about the ash thing but some woods, WA Redgum for instance, will not burn to white ash, just ask anyone who has used it in an open fire place for a season or two only to have their chimney catch fire like a giant roman candle due to being blocked with still combustible black gum. (shouldn't laugh, some folks have had their house burn down this way)

Anyhow Ben, other than to state that your wood is most likely either jarrah or karri, it would be a brave man who would confirm it's identity from an image. I know lots of seasoned woodies here in WA who can't tell the difference even when at hand, and this is in the home of both species. One would therefore need to question the validity of any determination in this regard being made by a salvage wood vendor who is 5000 kilometers away on the other side of the continent.

I can say this for certain, if it is karri and it was in contact with the ground, it would have been treated or it WOULD have been eaten in a few month, karri is like white ant ice-cream, simple as that. If it is karri and money was spent treating it, you would need to question why when soo much naturally insect resistant jarrah would have been available from the same source???

As for working it, that bit doesn't look too bad, sharpen your tools "properly" and wind back the blade adjuster and you should be fine.

Have fun,

Cheers

Kim

  I almost fell out of my chair reading that story!  Man, I'd hate to see my house burn down, though.  I witnessed a house fire up close and personal recently.  It was no fun at all, and I'll never forget the stench.

That board was surfaced on a power planer in a community woodshop when I still lived in Michigan a few years ago.  You can probably tell where there was a notch in the cutters.

Thanks for the advice.  Must... sharpen... tools!

Interesting thing about karri:  it's now being grown in FSC-certified plantations in... South Africa?!  Check it out:

http://www.fechters.co.za/sawmilling/sawmilling.htm

-Ben