The Front trim of the desk is not just cosmetic. It is intended to be a key part of the structure, bringing a level of stiffness to the whole desk. (Also making it look nice too!)
To give you some idea of the structural importance of this part, if you ignore the subframe for a moment and just consider the MDF top as a single length of material supported at both ends with the dimensions 2m long by 200mm wide and 17mm thick. You can find out the amount of bend a givem weight will cause. There is a handy website that will do this for you – which is good because my A Level Physics was a lifetime ago! But if you go to https://www.woodbin.com/calcs/sagulator/ you can pop in the dimensions and select the material and then add the load (either as a uniform load or a centre load, it will give you the deflection of the beam.
I chose a 100Kg centre load to simulate a um…, large person sitting on the desk. The amount of bend for unsupported MDF was a worrying 11.6cm. Which I suspect would quite possibly prove catastrophic.
Now if you add an oak edge 100mm by 22mm to the top creating an L section. and re-run the calculation the deflection for the same um… large person goes down to a mere 1.1mm. The tool doesn’t allow you to the subframe structure into the equation, but I think you can see that the overall desktop will pass the large seated musician test!
So here are the lengths of Oak as they came from my local cabinet maker friend who fortunately keeps it in stock (because this sort of thing is well beyond B&Q!)
Luckily my Brother-in-Law has a better equipped workshop that me, and he has a rather nice jointer-plainer. So I went up to him and we ran these through to get the pieces square and planed down to a finished 22mm x 100mm.
Back home and I set up the table saw with the blade at 82.5 degrees (90 – 7.5) so the resulting angle of the two pieces when joined would be 15 degrees. I also devised a pocket screw fixing plan:
Here are the first 2 pieces glued and screwed to the frame:
And here are some details of the fixings from underneath:
Finally with it all screwed ind glued into place I made up some end details to finish off the corners between the front trim and end cheeks. I then gave it all a sanding down to 320 grit and finished off with wire wool prior to finishing.
And here are some pictures after the finish has been applied
I still have to sort out the power sockets, and cable management around the back, and then the gear needs to be installed, so there may be one final entry in this diary, but from a construction point of view, the desk is now complete. I am really pleased with the way it’s turned out, and it will be a fine addition to the studio.