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I seem to remember reading a long time ago about gluing an ebony fretboard to a maple neck vs one of the various types of Rosewood (East Indian, Brazilian, Cocobolo, etc.) or Rosewood alternatives (Pau Ferro, Bubinga, etc.). It seemed to revolve around the typical moisture content of each wood. I've heard people reference the topic as if it's common knowledge that the marriage of Ebony and Maple has the potential to reek havoc on a neck if glued up in the wrong conditions. Mainly because Ebony is a drier species compared to other fretboard options. I want to say that there was some trick like storing them in separate climates until ready for gluing but I'm not positive.This is all I remember. I don't know the specifics and I can't seem to find the article where this concept was discussed.

Anyone know what I'm talking about?

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

That does not make sense. How could one species be drier than another unless they were stored in different conditions. A few years ago I was involved in a semi-production of maple archtops and I made 36 curly maple necks with ebony fretboards. I would have preferred to use carbon fiber rods but that was not part of the design. The woods were stored and seasoned in the same shop and there was no stability issues. They were glued with epoxy.

You might be thinking of the differential rates of expansion, widthways, with humidity. Water based glues would produce this effect, but it would mean the fretboard curling at the edges, not inducing a bow to the neck.

I've only used rosewood - I seem to recall ebony can expand more, but others will know for certain.

Epoxy should avoid this, if it's a major issue.

Interesting... One of my greatest successes was a short scale bass I built for someone back in 2016 and I did glue the Ebony FB with Epoxy for whatever reason.

I'm nearing the end of a pile of Cocobolo fretboards that others have advised me not to use due to it's oily nature. I used Polyurethane glue on them and I don't think they will come apart (for better or for worse) anytime this century. Does anyone know if the two glues are pretty much the same in use? I realize they are different chemical makeups.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

I read about this a long time ago and did my own experiment.

I took a cut off of both ebony and maple, both were about 6" long and I edge glued the ebony to the maple using HHG. I didn't do much prep other than scraping both surfaces with a cabinet scraper. Let it sit for a few days and tried breaking the two piece apart.

I couldn't break them apart no matter how hard I tried (using my hands). I sat it down on my bench and for the next 2 years anyone that came into my shop I asked if they could break them. No one ever was able to separate them and It eventually went into my scrap box. I think it is still somewhere in my shop but I have not seen it for some time now.

It convinced me that there really is no issue with these 2 woods at least with HHG as long as you reasonably prep both parts.

Not sure my little (unofficial) experiment helps anyone or not but that is what I did to try to check this out.

Cheers,
Bob