mahogany desk build questions

[loc0]

Hello.

Recently I've got my hands on quite a lot of mahogany boards (some of it rescued from a lumberyard set on fire 30? years ago). Boards are random. The nicest and oldest are nearly 2000x300x60mm plus many random bits and boobs (furniture trims, tables, sink plates) that were salvaged/ collected during the working days of the gentleman who sold me the whole lot. Initially, when I went to meet him I thought I'm only taking a few boards that I can use for accent pieces, maybe drawer fronts for my amateur projects but it turned out he was not aware of how much he accumulated over the years so I come back home with a car filled with some lovely stuff. Enough to build a desk: 1650x650x720. Top 30-35mm thick (depending on how much I can yield from the material I have). Framework from solid and/ or laminated pieces 50x50xXX pieces.
Now on to the subject. One of the youtubers (Jason - Bourbon Moth) who visited UK to help our forum member with his bed build posted a video:

I really like the design and I really don't want to mess this up . Few pics to show what I will try to achieve.
1st issue is - I don't have enough thick boards to make my frame from solid pieces so I will need to laminate them. The frame will be assembled with dominos and I assume lamination should not give me any bother?
2nd issue was pointed out by one of the FB woodworking group member "Can’t help but think this design will eventually bow at the front. Given the top can’t be tightly screwed to it to allow wood movement i’d expect the front brace to sag sooner or later". Would that be true?
3rd issue is also from FB advice "One issue is that the legs need to run to the top of the frame and rails morticed into them. Not the legs morticed into the long rails.". Once I thought of it and looked at how tables are traditionally assembled I realised I may indeed have to change Jason's design.
Any thoughts, pointers, advices will be greatly appreciated.

Regards
Marcin

 

[Hornbeam]

Laminating your legs would be OK. however I am always careful when using compressed biscuits or dominos as they tend to swell when glued and there is a small possibility of blowing the lamination apart, Can you take your extra wood from the drawer fronts and do the drawer fronts as a planted on construction veneer about 2.5mm thick
I do not think there is a great risk of the top sagging. There is a substantial underframe and at the back there is a lower rail as well.
It is normal practice to run the legs to the top and mortice or lap dovetail the rails into the leg. I think this would be better but I also see no reason why the design as shown wouldnt be OK, My only concern would be when picking up and moving the piece as with the construction as shown any weight in the cabinets will try and pull the top joint apart

 

[loc0]

Thank you very much Hornbeam!

 

[Hornbeam]

Hi loc0. Watched the video and would make a couple of comments
There is no need to cut the internal parts of teh frame as L sections. Wasteful of timber and way too much short grain
I disagree with the comments in the video regarding the cabinet construction. His approach does not allow for timber movement and is more likely to fail, I would do the cabinets as veneered assuming you want the grain to run as in the video otherwise use solid with grain running round the top bottom and sides Then fit a veneered ply back into a rebate

 

[loc0]

Thanks again! Weekend closing in so I will get my project going

 

[gasman]

I made something similar last year from old mahogany - but I used book matched flame mahogany veneer for the sides and drawer fronts etc on a plywood base and had a skiver leather inlay - all worked out quite well

 

[johnnyb]

mahogany was an amazing wood. medium hard but very easy to plane work. extremely stable (big chunks will move a bit when cut.)
open grain and full of tannic acid.
the bad side is it feels old. no matter what you make it looks like an antique. the world wasted much of this king of wood. sapele is a poor substitute.