Teaching Station: Sit/Stand Desk

January 7, 2021   Martin Jones
A sit/stand desk for remote training.

Sit/Stand desks for remote instruction have different needs to desks used for software development. I didn’t find a suitable one that I could buy so I made my own.

Mk III Teaching station picture

Mk III Teaching Station (Raised)

I provide an overview of my teaching station’s evolution in a recent post. This post explores the build of the sit/stand desk. I guess, to be more accurate, it’s a sit/stand converter because I didn’t build the desk part.

COVID-19 forced remote teaching to be my only means of delivery. I teach best while standing, so I needed a standing solution. Being fortunate to have both the space and the tools, I quickly created the Mk I early in COVID-19. Although it was capable of converting into a sitting position, this was not easy, so it stayed a standing station. I taught standing all day, and despite being tiring, it appeared to be working fine.

I augmented the Mk I with a standing chair (I never knew they existed) to help with fatigue. I bought a LeanRite Elite from Ergo impact. It’s not cheap – it was possibly the most expensive single purchase I made for the teaching station. Expensive, but I think worth it. I tend to lean on it when listening to questions and sometimes sit on it during lab time.

There were a couple of problems with a standing only approach though. I developed a disturbing clicking and loose feeling in both knees (now gone (the feeling, not the knee)). I think it was likely because my legs would get bored and move into a ’tree pose’ like position where the foot of one leg pressed against the other inside knee. The other problem was how much more tiring it is to stand when someone else is teaching. Until then, I had been the only instructor, but when a new contract had me teaching as part of a team I really wanted to sit down.

Sit/stand desks and converters already exist, of course, but my searches failed to one that met the criteria of extension, maximum load, and speed of changing between sit and stand.

The extension needs to be long enough so that a camera set to see my face in a seated position is also in the right place when the sit/stand desk is in the standing position. Most sit/stand desks won’t go high enough.

The sit/stand desk must be able to support plenty of weight. There is potentially more equipment on the shelf that lifts than there would be as a developer. My shelf has two regular monitors, two small panel monitors, the teleprompter, a stream deck, and a Wacom tablet on its own pull out tray. That doesn’t sound too bad, does it? Ahhh, now add in zero wobble. The main camera is on that shelf - it’s not permitted to vibrate. No vibration eliminates designs that involve scissor hinges. A rail is probably the only option, but it will need to be a really wide rail (or two separate rails).

Lastly, I may need to move from seated to standing, or vice versa, while teaching, or during a short break. Although a linear actuator is cool, it’s too slow. Hand lift is the quickest option here.

Sit/Stand Parts

Slotted Metal Angle and Linear Rails

I settled on building a riser using slotted metal angle with a shelf that ran on 20mm linear rail slides. These parts are laid out (some already assembled) in the photo above.

Using the slotted metal angle allowed some wiggle room for adjustments. If you build your own, then it should be relatively easy to find at a DIY store. The rails were harder to find. I initially bought 600mm long rails. They turned out to be too short, and I ordered some new 750mm long rails. The 600mm is shown in these photos, but, again, get the longer one. There are different thicknesses, so I went for the larger 20mm. I’m not sure that is necessary - the rails do not normally bear any weight.

Assembled Riser (rear)

Assembled Riser (rear)

Assembled Riser (front)

Assembled Riser (front)

Once the angle is bolted together, especially in a triangle, it is firm - zero vibration. The rails are yet to be mounted in the photo above. Note how the riser slopes back; this is a good thing. When you stand up, your face will end up a little closer to the camera. Hence the standing position should be set back from the seated position. Also, the base of the triangle will need to be deep enough so that the riser doesn’t tip forward when the shelf is attached.

The bottom of the riser will be fixed to a board that sits on top of the desk. That’s not shown here because I waited until I could position it on the actual desk.

Also, note the angle that isn’t part of the structure, running flush with the wood’s edge. You’ll see later how this is used to fix the shelf in a raised position.

Shelf Carriage

Shelf Carriage

Shelf Carriage Bearings

Shelf Carriage Bearings

The shelf will be attached to the carriage shown. At this stage, I just wanted to attach the carriage, getting the rails straight. Drilling holes in the correct place is a challenge because the rails must be perfectly parallel, and the bearings must be mounted in the proper place. Don’t drill holes ahead of time - find where things ‘sit’, and then drill with the rails in place. For the bearings I cheated a little. They are made to accept a metric bolt, and I tried to find it in the local DIY store, but I live in America. Instead, I went for a thinner bolt and used a washer and nut. This turned out to be a good move - it has some wiggle room. The rail can force the bearing’s position, and then the nut can be tightened, fixing the bearing in the right location. I don’t remember the details, but there were many small stages in getting everything in the right place. Once done, it is absolutely rock solid.

The rails help guide the shelf up and down. The Mk I didn’t have rails, and I could move the shelf by lifting it and then slotting it into a different location. That was the plan, but moving the shelf was practically unsafe, not because of the weight but because of the leverage of the monitors with all their weight attached to the back edge. The rails are necessary to restrict the motion of the shelf to linear.

Shelf Fitted

Shelf Fitted to Carriage

The photo above shows the shelf fitted to the carriage. The shelf is 3/4" plywood - remember to sand! A slot was cut in the carriage, and a tongue in the shelf. I filed the slot so that the shelf fitted tightly at the correct angle. There are also additional supporting pieces of wood that can be seen in the next photo.

The photo above also shows that the angle is now attached to a bottom piece of plywood. This plywood will get clamped to the desk (visible in a later photo).

Shelf Underside

Shelf Underside

The photo above shows one of the additional pieces of wood that fixes the shelf to the carriage. There is also one behind, and above. It’s important to get the angles of these correct.

You can also see the bolt used to fix the shelf in place. This is what the pieces of angle are for along the sides of the riser. Beware! The holes need to match up horizontally, and I found out that angle often has breaks in the pattern. Make sure you cut these two pieces of angle to have the same pattern at least at the top.

The position of the bolts is deliberate. Should you build one of these - think carefully where the bolts go. When lifting or lowering the shelf, your arms reach under the shelf and support it. You need to be able to pull and push the bolts while holding the weight of the shelf. These are in a natural position.

Equipment Mounting (front)

Equipment Mounting (front)

Equipment Mounting (rear)

Equipment Mounting (rear)

There are better, more professional solutions for equipment mounting than shown in the two photos above, but I didn’t have the time to wait for it to be delivered, and I had a lot of copper pipe I could recycle from the Mk II. The equipment that is mounted has changed over time, but using the pipe clips has worked well. They allow equipment to be repositioned vertically, having enough grip to hold light equipment in place. I don’t currently use the full height of the pipe.

Cabling (Standing Position)

Cabling (Standing Position)

The photo above shows a more complete station in the standing position, from behind. The cables are fixed in place both on the carriage, and on the riser using wire ties. The cables need to be long enough so that they just reach, without too much excess in the standing position. By wire tieing at both the carriage and riser, changing between standing and sitting will not cause strain and movement.

There are three other things to note on this photo. I added a bolt that serves as a stop once the station has been raised to the maximum level for me. It’s a nice side effect of the angle that you don’t have to calculate this before use. You can see the clamps from this side holding the bottom board securely to the desk. Lastly, you can see reflective cloth hanging from the shelf. Without this, a rather unflattering light illuminates the instructor from beneath on a sunny day! This screen reflects that light back, making it useful.

Cabling (Seated Position)

Cabling (Seated Position)

This photo shows the cables with the shelf in the seated position. The crossbar where the cables are tied had to be moved lower from its original position. It has to be positioned so that the length of cable from the riser to the carriage works in both positions - don’t fully tighten the wire ties too soon! The metal angle can be sharp, so I protected the cables by adding a piece of wood with a bevelled edge.

Make sure you buy cables that are long enough. 6 Foot cables are NOT long enough, go for 9 Foot, 10 Foot, or 3 Metre cables at least. You might also have spotted that I have my computer sitting on a shelf built onto the side of the desk.

Time

Building the sit/stand converter requires substantial time. The bulk of the work took a couple of days, although that included some experimentation not described here. There have been refinements over time as well. If you need it for teaching, I would give yourself at least a week, assuming you have the parts available.

Costs

I’ll try to summarize the costs here, but if you have the tools for the work, there is a good chance you will have some of this material available already.

Cost (USD) Item
80.00 Rails
75.00 Metal Angle
20.00 Nuts/Bolts
50.00 Wood
10.00 Locking Bolts
10.00 Clamps
60.00 Copper Pipe
305.00

Summary

If you have the time, space, and tools, you can build a sit/stand converter that better meets instructional needs. Given the time it takes, I would only recommend it if you strongly believe it will make a difference in your teaching.