mahogany versus "mahogany"

[werner]

Hi,
have to buy wood for the shelf 9cmx3.5cm total length 11m
on plan mahogany (american honduras)but not available in great lengths here and terribly expensive (is this better in america?); can the shelf safely be made of Sipo Utile? 6meter length is no problem and price is reasonable. the beams should, also following plan, be made of mahogany and locked with a half dove tail in the shelf.
Could there be a problem <I do not know about?Sipo is somewhat heavier, less elastic and works only little more in changing humidity compares to real mahogany.
Would this be a good choice or not? what could be a better choice?
regards ,
Werner

[Bob Smalser]

Type. Hardwood. Other Names. Also known as abebay, afau-konkonti, assie, efuodwe,. kosi-kosi, mebrou zuiri, okeong, and sipo. ...

Other Common Names: Efuodwe (Ghana), Sipo (ivory Coast), Okeong (Nigeria), Assie (Cameroon), Kosi-Kosi (Gabon), Mufumbi (Uganda). Distribution: Principally from West and Central Africa.

I can find it on the net, but not in any of my wood encyclopedias with properties.

[werner]

Bob,
Sipo =(etandroprhragma utile family of meliacea)is called utile in GB .
I think it will be okay to use it for the shelf since looking at the numbers the mechanical strength seems better than real mahogany;
But only the dovetail joints for the deckbeams wory me.Will the shelf be strong enough to hold the stresses at these joints? Am I right to think that there will be strong pressure and pulling forces on these joints? (narrow boat with long open cockpit).
greetings,
Werner

[Thad]

On the shelf I think you want to have relatively straight grain most of all. Most woods specified for clamps and shelfs are straight grained, moderately hard, but generally tough, Douglas fir (Oregon Pine) and longleaf pine being prime candidates. On the dovetails, I would not expect great pulling pressure on the joints. You might get some with swelling of the deck. Good practice is to install tie rod bolts between the carlin and the clamp/shelf structure.

[Bob Smalser]

I think it will be okay to use it for the shelf since looking at the numbers the mechanical strength seems better than real mahogany;

But only the dovetail joints for the deckbeams wory me.Will the shelf be strong enough to hold the stresses at these joints? Am I right to think that there will be strong pressure and pulling forces on these joints? (narrow boat with long open cockpit).
greetings,
Werner As important as this framing member is, I'd sure want to do the calculations on the durability and engineering properties of this species (which I don't have) against the species and scantling size specified by architect or engineer.

I suspect it's just fine...but why not remove all doubt?