fernandraynaud - 8-27-2009 at 03:27 AM
I would like to make a rose for an instrument. Time for the old Dremel. What sort of woods are good to use, and what thickness? Is veneer too thin?
What are some considerations? Effect on sound?
Is there a good technique for generating a drawing and transferring to the wood? Maybe laser printing and heating it up with an iron? Good source of
classical designs?
Thanks!
Dr. Oud - 8-28-2009 at 09:28 AM
You can use any hard wood, maple is best, but solid wood should be at least 4mm thick. Solid wood must be flat grained and very dense.I prefer a
marine plywood, 2mm thick, made from maple veneers, found in hobby stores and marine (boats) supply stores.
Veneer is too thin.
There is no effect on the sound.
You can print your design and glue the print-out on the wood to drill and cut it, or draw the design directly on the material. After drilling a hole
in every open area, I use a jewler's saw to cut the design, others use a power scroll saw, but it must have a very slow speed to avoid splintering,
and a quick change blade.
I don't know anyone using a dremel, it's too hard to control.
fernandraynaud - 8-28-2009 at 01:35 PM
Hi, Richard,
Can you please explain the reasoning behind some of these "rules"?
Why so thick? Other than being fragile, why does a thin veneer not work well?
It would seem altering the opening with a rose would change the port tuning a bit. Is it insignificant because only low frequencies are involved (and
high frequencies come mostly off the face?)
Is it possible to buy a (wood) rose somewhere?
Thanks
Dr. Oud - 8-31-2009 at 10:05 AM
Veneer will simply fall apart when you cut the pattern out or soon after - it is just too fragile. A laminate (plywood) of at least 3 layers of
veneer might work.
The sound is produced by the face from the bridge to the sound hole. The face from the sound hole up to the neck is structural only, it produces no
significant sound due to the cut out of the hole and diminished vibration of the braces. "Port tuning?" I never heard of it in relation to ouds. I
don't think the size or grillwork would have any affect. Only if the hole is covered completely or nearly so would it affect the resonant effect of
the body/chamber.
Some makers will make a rose for you, but it has to be made to fit your oud. I am not able to accept a new project at this time.
Brian Prunka - 8-31-2009 at 01:27 PM
If you can supply a design, there are companies that will laser-cut one for you. Lasers tend to burn the edges of the wood, which many people
dislike. I don't necessarily mind it, it just looks black.
fernandraynaud - 8-31-2009 at 06:12 PM
Ah, so. Excellent points and ideas. Thanks. I'm clamping a 3 cross-grain stack of cherry veneer that I happen to have, using that crappo carpentry
glue -- I don't foresee EVER wanting to separate the plys.
BTW, is it generally safe to try heat to unglue an old rose from an oud? I would think they use animal glue, or are we running into "modern" glues
that will not unbond if gently heated? What then?
Dr. Oud - 9-1-2009 at 12:36 PM
It usually is hide glue, try a little warm water and gently pry it off with a thin blade - artist pallette knife is ideal. If it doesn't soften, dry
heat at low heat gun or high hair dryer setting and the pallette knife again.