Gluing Ebony to Ebony

[Gail Hester]

I’d like to build a mandolin with Macassar Ebony back and sides and an Engelmann Spruce top. I’ve seen some guitars made with this combination and have been intrigued for awhile with the idea of building a mandolin with Macassar. The stock I have will require a two piece back.

My problem is that I’ve tried gluing some test pieces with hide glue without success, they seem to come apart too easily. I’ve even tried cleaning the gluing surface with acetone and it doesn’t seem to help. The Macassar guitars I’ve seen have a back strip of another material which eliminates the need to glue Macassar to Macassar.

Do I need to use a back strip or has anyone had success gluing Ebony to Ebony or specifically Macassar to Macassar? I’d really appreciate any tips, tricks or advice on the subject.

[Lane Pryce]

Have you tried or considered a maple strip? I played a mandolin a while back that had a two piece back constructed of a something that looked like ebony and the pieces were jonined by a maple strip. The owner/maker of the mandolin said the maple strip joined the back halves by a scarf joint. Only about an 1/8" of the maple was visable. It had maple binding on it as well. Very nice contrast between the lite and dark woods. Lp

[Chris Baird]

You might try epoxy. I believe there are epoxies sold that specifically state that they work on oily tropical woods.

[Luthier]

I have found the regular white, polyvinyl Glue such as Elmers could be used with decent results. #I also have used Titebond and have had great results with many exotics.

The one thing that scares me just a little is bending the Ebony.

Don

[douglas2cats]

Polyurethane glues are touted as being good for gluing oily exotic stuff too. Not sure if it's any better/worse/equal than epoxy but I've used it gluing teak (w/o bothering to pre-clean with acetone) with good results - the stuff is still glued together after 4 years.

[Gail Hester]

Thanks for the help you guys. Has anyone tried any of the cyanoacrylate glues with macassar.

[peter.coombe]

Yes I use a cyanoacrylate glue to glue my pickguard clamps which are made from macassar ebony. I have tried titebond and epoxy and the only thing that has not failed yet is the cyanoacrylate. An Ebony back is a nice idea, but have you though about the weight? Also, I hope you have a good piece of macassar because it tends to split readily. Anything of any size is likely to have internal splits. I have also thought about using macassar for a back, and have a piece of suitable size, but have been reluctant to cut it because it almost certainly has internal splits, unless I get real lucky.

[grsnovi]

I've used cynoacrylate to glue ebony binding pieces in place but not to do a "join". I've used phenol resorcinol to join ebony and rosewood with good results.

[Gail Hester]

Thanks again everyone, great suggestions and I’ll be trying most of them. Weight and the potential for cracking are very valid concerns. I do have a bunch of Macassar since I had to buy it in 14 foot lengths and I should be able to find some without any splitting. It may split while carving, that’s an unknown until I try it. If it’s not stable to work with I’ll stop there before I bend the sides.

Here’s a look at some of the Macassar I have. I’ve been using it in strategic areas such as the extensions, truss rod covers and pick guards.

[Gail Hester]

The rest of it.

[Michael Lewis]

Very nice Gail!

[Luthier]

I am still sitting on a small quantity of the pure black Gaboon Ebony I mananged to find at a log import company during my college daze. #Its running out though.

Don

[sunburst]

I am still sitting on a small quantity of the pure black Gaboon Ebony I mananged to find at a log import company during my college daze. Its running out though.

Don
You just posted that to tease and provoke envy didn't you?
"If you don't have enough to share with the rest of the class,..." http://www.mandolincafe.net/iB_html/non-cgi/emoticons/smile.gif

[fireman]

Ebony is naturally too cold to glue with hide glue. I heat the ebony up with a flame before glueing. If you don't, the glue will gel before it is suppose to. It glues together wonderfully with a little heat.

Brent

[Gail Hester]

Brent, that makes so much sense. I usually make sure everything is warm but I didn’t with the Ebony. Thanks.

[Luthier]

Sunburst, I never could share with the rest of the class...
If I may quote a line from Finding Nemo....(mine..mine...mine...mine....)


Don