Eucalyptus as cleat material . .

[Pete McCrary]

Fellow builders:

I'm about to start the build-out of a cs20.3 hull and have a local source for Eucalyptus -- also called Grandis by the vendor. Yould any of you have opinions as to its appropriateness for cleat material? Any known drawbacks?

[wasserboot]

It is not so easy to work with chisel and plane. But it is very durable and fungi-resistant.
It is used for windows. So it should be no problem to use it in modern plywood-epoxi boatbuilding

[PAR]

There are a lot of different "Eucalyptus" subgenus, from mountain ash to blue gum. It's physical properties can rage quite a bit, from Deglupta (Mindango Gum) with density similar to Douglas fir (32 pounds, cu. ft.) to really dense stuff at 68 pounds cu. ft. to Coolibah at 68 pounds cu. ft. Generally, the more common varieties are in the 50 to 55 pound range. Most are moderately resistant to rot, though can be prone to insects. It glues and machines well, though some genus are better than others. Get the interlocked grain varieties (Coolibah, Jarrah, etc.), so cleats will stay together and limit checking too. Also be carefull about cutting and machining this stuff, as it can cause heath issues for some. So, find out what kind of Euc tree they've harvested, if you can.

[pwillems]

I am intending to do a hoop pine / jarah lamination for seats, gunwales, center board and rudder of my SpinDrift 11N. Jarah has a beautiful deep red color so it should look great, but the stuff is only slightly lighter (or softer) than cast iron. Therefore it is going to be a lamination alternating 20mm hoop pine and 10mm jarah.

[Peter HK]

I've read that Jarrah oxidises very quickly when cut and this oxide layer can impair bonding with epoxy. It is said that even an hour is too long and it is best to sand the jarrah immediately before applying epoxy. No personal experience but I suppose it is better safe than sorry.

Cheers

Peter HK