Expert: Greg Scholl - 3/1/2009

Question
QUESTION: Hello, I'm attempting to make a humidor cabinet for my father in law.  It will be 65" tall - 15" deep and 24" wide.

I made two 65" x 15" for the sides out of mahogany.  I used 4/4 stock, but I took it down to 1/2" so I could line it with 1/2" spanish cedar.    I found some 4/4 spanish cedar at a mill shop and asked if they could cut down to 1/2" or 3/8" with a band saw. I didn't want to have to waste 1/2" in my planner like I had with the mahogany.  They said they could and that I need to discuss it with someone during the week.  
I have a few questions I was hoping you could help me with.
Do you think 3/8" is thick enough?  Once glued to the mahogany it would be 7/8" thick.
Will I be able to glue them up into a panel?
Would you recommend gluing them up into panels first and then glue the two panels together (face gluing)  or would you do the glue the mahogany and cedar together while gluing up the cedar, sort of using the mahogany as a backer board?

Any tips you have would be greatly appreciated!

Thank you,
Steve

ANSWER: Hey Steve, I'm quite concerned about your construction method here, as such a large side panel (65x15),that is only 1/2" thick will be prone to movement, and probable warpage, splitting,etc. Additionally, the Cedar shouldn't be glued to the Mahogany, but should instead "float" inside the cabinet, like a box within a box, as it will expand and contract differently than the Mahogany. I don't think the thickness of the Cedar is as important as the thickness of the Mahogany, as the Cedar isn't structural, (and shouldn't be).  If you were using a 4/4 or even 5/4 frame and panel type construction for these larger panels of Mahogany, with the thinner 1/2" panels floating in the thicker frame, and then installing the 1/4"-3/8" Cedar on the inside as a separate "floating" liner, I would feel much better about the integrity of the cabinet...what type of construction are you using in the Mahogany carcase? What's the base, door and top going to consist of? ..and will they be constructed as to maintain this integrity as well? All these elements need to be constructed so as to allow for rigidity of the frame, with typical cabinet making principles, while allowing for natural expansion and contraction relative to the quite different properties of the softer Cedar...

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QUESTION: Well thank you before I waste even more money on this crazy thing.  You definitely informed me of a number of things I was un-aware of.  I had no idea that 1/2" mahogany wouldn't be strong enough.  I also didn't know you can't face glue wood of different types.  The mahogany was 4/4, I thinned it down so I could add the 1/2" of cedar giving the whole thing a thickness of 1" .  My plan was to just create a solid box using the mahogany/cedar panels on the sides, bottom, and top.  Then use birch plywood for the back panel along with a cedar panel as a liner.  After reading your reply, I'm done with this. I'm not qualified to do this.  I don't want to invest $1000 in wood and a humidifier to end up with a humidor that is splitting, cupping, or develop cracks.  I can't image how to build a floating box that could be placed into the other cabinet that would be nice and tight with the outside box.  Which means if you open the door, you'd probably see a gap somewhere between the external cabinet and the lined box.  I appreciate you taking the time to answer my original post.  I'm just out of my league on this one.     Now I'm trying to think of what I could do with all the mahogany I have.  I just found out we are having a baby, maybe I could make a toy chest.    Do you think I should cut these panels down and make them into raised panels that could be placed in thicker 3/4" or 7/8" stiles and rails? Would they by suitable?   To make the panels, I cut them down to 3" and 4" wide pieces (to reduce movement) and alternated the growth rings to reduce cupping. I flattened on jointer and then reduced the thickness to 1/2" on the planner.  I then used biscuits to glue the panels together using some oak clamping cauls I made.  I made these panels about a year ago and returned to them this last week.  They are still very flat and look very nice.  Thanks for your time!

Answer
Hi Steve, I wasn't trying to talk you out of the project, and it sounds to me like you have the abilities to do a project like this. You could make raised panels,( although 1/2" is still pretty thin for this), or just use a flat panel construction, which is still nice looking with good wood, but more importantly would be the proper construction. Have you researched the project at all? I took the liberty of poking around the 'net, and came up with a few sites, and I'm wondering about books, perhaps something from Taunton Press.....these cabinet making techniques are really standard stuff, but it is important to do it right if you're going to invest all that time and money in this type of thing...and typically the Cedar lining is 3/8"- 1/4", and in a Humidor of that size you would have to figure a way to install a paneled system, perhaps with some members glued to the Mahogany, but the majority of the Cedar "floating". Again, a cabinet within a cabinet. It's also important for the Humidor to have the capacity to keep in moisture,to add and monitor that humidity level with some sort of Hygrometer and moisture humidifier, and to have a proper seal when closed, and again, all this can only be achieved with fairly advanced cabinet making techniques. It's an ambitious project, and it would produce a true heirloom cabinet that I'm sure would bring pride and good smoking to you and your father in law for many years...so don't give up...just know going in that what you're taking on is something that requires a high skill level, and proper techniques and methods to pull off. The panels you have constructed were done right, and if the wood was the proper moisture content when you did them, I would expect to have them remain stable as Mahogany is quite a stable furniture wood, but you will be raising the humidity substantially inside the "box", (up to 70%) and likely it will swing wildly outside the Humidor from season to season ( as low as 10-12%)....and this is where you'll have issues in any wooden construction....again, I hope it's not my fault for discouraging you from this project....perhaps you could construct a smaller Humidor to start...this would teach you the basics, and help you develop the techniques, and I have seen many table top Humidors that are beautifully made, and even some kits...best of luck and post back if need be- Greg

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