Armoire Project

Part one: the carcase

I am building an armoire (small wardrobe) for the guest bedroom.

Lynndy asked for a small cabinet that could hang clothes as well as including a large drawer. The brief is that it must fit into a small room and, therefore, needs to be quite shallow (18” deep). So my design arranges the hanging direction forward rather than sideways. There will be a central rail accessed by two doors.

Here I overview the construction of the carcass. I am thinking of calling it the "dovetailed cabinet". The sides and upper side are through-dovetailed, and the lower two dividers are sliding dovetails.

The remainder of the design (two raised panel doors and one long drawer) will be attached to face frames. There will be a base and a top. In all, the armoire will be about 51” tall and 36” wide, so there is room for a mirror on the wall above, and the top may be used as a dressing table.

Panels were built up of ¾” thick Tasmanian Oak boards …

… and then dovetailed together.

The Sliding dovetails

An article was completed on sliding dovetails based on the work done here. This has detailed and step-by-step pictures. Here are a couple, for interest ..

A dovetail plane for the male joint …

Sawing the lines for the female joint …

After removing the waste, cleaning up with a router plane …

A finished joint (to be trimmed later) …

Now the depth of these sliding dovetails created some discussion on WoodCentral. Some, argued that they were too deep and would weaken the case side, while others replied that they would have done the same as I.

I replied …

The dovetail depth is 5/16" in a 3/4" thick casing.

My understanding is that the Rule of Thumb is that it should be between 1/3 and 1/2 the thickness. So my dovetail depth is within the recommended range.

The lower end of the cabinet has another section (a M&T frame for the drawer), which is also dovetailed. This is expected to add further rigidity to the case side (that is, reduce any flex, which would place stress on a dovetail joint).

The cabinet has a 3/8" deep rebate on all sides at the rear for the attachment of the rear panel. The rear panel will be made up of hardwood boards joined with half-laps. This will add considerable rigidity to the cabinet.

The front of the cabinet with be reinforced with a 3/4" thick face frame. This is planned to be attached by a dado at the rear of the face frame. The dado will further reduce any twist (and, thereby, any stressing of the dovetail).

“John of Baltimore” wrote:

If I recall correctly, for a full length tapered sliding dovetail (a suitable joint for joining a shelf to a case side), Tage Frid (in Vol. 1 of his book) recommends the depth of a tapered sliding dovetail housing to be 1/3 the thickness of the case side. However, for material of any thickness, the tapered dovetail housing should not exceed 1/2".

Thus, by employing this convention, a 3/4" case side would receive a 1/4" deep tapered dovetail housing.

On a further note, I believe that assessing the weakness caused by such joints requires a deeper inquiry into whether the complete assemby is rigid enough to prevent deflection of the case side at this weak point.

For instance, would the failure of multiple joints on the other side of the case be required to cause deflection at the weak point? For a case piece having several drawer assemblies or shelves joined using sliding dovetails, it appears to me that the localized weaknesses wouldn't be a serious problem.

The rebated back of the cabinet

I know it is not the ideal way to do it, but I used a stopped rebate at the upper panel ...

Step 1: Do as much as can be done with rebate plane (until it no longer cuts)...

Step two: Finish off with a router plane ...

Step three: Completed stopped rebate (of course I later discovered that I needed to extend it by 1/4"!) ...

The side panels were rebated in the usual manner ..

The Mortice-and-Tenon Joints

The complete tutorial on building M&T joints is found here.

A few images …

Morticing …

Sawing the cheeks …

Tuning the cheeks …

The mortice and the tenon …

The final result …

Assembly

The issue of how to assemble large pieces in a small workshop once again reared its ugly head. The questions for the Learned Readers are how do you cope with largish assemblies (a) on your own, (b) without an assembly table, and (c) in a small shop?

Step one - I attached two sides, balancing the free end on a small ladder while I connected the dovetails at the other side. Sorry no picture. You will have to use your imagination!

Step two - I held the third side by clamping it to the bench, and then brought the first assembly over to it and joined the two. This is easier said than done as it must go in square. Use of levels, corner braces, and much swearing is essential.

Step three - after the glue has dried, turn it on its side and slide in the upper sliding partition. Turn upright, check for square, and clamp until dry.

Step four - add the lower section. This is a mortice and tenoned frame (not a solid section) upon which the large drawer will run. This connects via another sliding dovetail. Here it is (upsidedown) ...

Moving this Tasmanian Oak frame was hard enough. Balancing it was harder ... where is the third hand?!

Regards from Perth

Derek

December 2009