Wall Mounted Folding Desktop - Height Adjustable and Tilting Top

This was a space saving project, I wanted to have a small desk that could fold and free space when not used.

Inspired by some architect or drawing tables, I wanted it to be adjustable in height (use it while seating or standing) and be able to tilt the desktop.

1. oak, beech and holly
2. brass (or wood)
3. steel plates
4. glue
5. screws

I used the following tools :

1. radial saw
2. planer
3. router
4. lathe

The design was probably the most time consuming part of this projects.

I used paper and pencil as well as 3D software to help validating my choices (mechanical : sliding, proper geometry, locking...but also overall look)

The desktop slides within the two rails, the upper shelve act as a counter weight with a rope and pulley linking both parts.

Once at the desired height it is secured in position with the two lower cam locks. The two upper cam locks can be used to secure the desktop in a tilted position.

I came up with this design which leads to the following parts :

- 2 mounting rails (each made of 3 pieces glued together)

dimensions are :

2x 7x220cm thickness 2,5 cm

4x 2,2x220cm

- 2 transversal plates (to attach the rails together, allow mounting on the wall)

2x 74x7 cm

- the desktop : (50x60cm)

made of 2x 25x60 planks

2x 38x4,5 cm supports

- articulated desk support :

made of 2x 50x4 cm (with 2 15mm holes)

- bottom sliding guides :

2x 35x4 (with one 15mm hole)

2x 35x2,4

- top support guides :

2x 20x2,4 (with one 15mm hole)

- cam locks (x4) for supports and desktop locking against the rails

I made then from beech...oak is not the nice when turned)

for each cam lock :

2 cylinders 4 cm diameter, 2cm thick, 1cm diameter holes (2 mm off center)

1 metallic plate, 1cm diameter hole , 5mm thick, 2,5x13cm (re-cut after placement on rail)

3mm diameter brass rod

10mm diameter brass rod

one wood handle

- counter weight shelve

- 4x pulleys

Cut, plane and sand all parts.

Most of the parts are pretty simple to prepare as they are simple rectangles, some are rounded a bit

All desktop articulations are made of 15mm holes and 15mm beech tenon

I make all long cut with my special tool :) to be as accurate as possible

glue parts, plane and sand

Cut slot that will allow sliding of cam locks

The sliding slot needs to be above 5 mm to allow the cam locks to move smoothly

My saw cut is about 3mm wide. I made two passes and inserted a thin plate between the ruler and the saw to reach the desired width. See photo details for explanations.

Clean one edge of each plank with router to have a nice adjustment, then glue parts together.

Once glued together, the top edges can be aligned and cleaned again with a router using a bit with ball bearing and a ruler.

Those are the two arm that supports the desktop.

This is an important part of the project... Since the desktop is adjustable, it needs to be secured when at the desired position. This is done with 4 cam locks. The principle is easy, it is a wood cylinder that is drilled 2mm away from its center, a metallic axis is inserted in this hole. When the cylinder turn around this axis it can "bite" the rail and secure everything in place.

We have 4 cam locks with different uses....for all of them we want the handle on the front side

For the lower ones we want the cam lock to naturally locks when the desk tries to go downward (counter the desk weight)

For the upper one we want the lock to naturally locks when the desk tries to go upward (counter the movement if I place my arms on the desk edge)

For each of them it impacts the position of the handle compared to the metallic core

The easiest to avoid mistakes is to prepare the 8 cylinders with the off center hole and wait before drill the handle hole

the two bottom ones are the easiest to install since one part is accessible from outside the rail. we will use this part to insert pins and secure the wood and metallic part together

For the two upper one the wood part is inside the rail and will not be accessible once assembled.

Start by assembling the parts, drill 3mm holes through the wood cam and the metallic core, insert the 3mm brass rod to hold them in place.

The shelve has an hidden compartment where you can put weight to balance the desktop.

The frame with the two rails is secured on the wall.

We can then add the supports, the desktop, the pulleys and the counter weigh shelve