Galerie Circuit suggested that the pedestals for the Knock on Wood installation should be made of unpainted 19mm MDF instead of the traditional white-painted version that would get lost in their large white space. Great idea! But these fine pedestals would be thrown away after the show was over.

Since I designed the pedestals specifically for these instruments, I suggested that they might be constructed so that they could be taken apart, transported as flat panels, and reused at another Knock on Wood venue.
a list of sizes for the pedestals

Circuit ordered the MDF cut to size.

We assembled the MDF panels using "removable" Tesa double-sided tape. Normally, it is intended for fixing carpets and can be removed without leaving a sticky residue. Assembly was faster and cleaner than using normal wood glue but of course not as strong.

The tape is 50mm wide. It was stuck along the join, about 3mm from the outside edge of the join and the remaining strip was sliced off with a sharp knife. The remaining strip was used for two more joins.

picture of a clamp and nail
Having tried doing it alone, I can say that aligning the join is definitely a two-person job, each checking the alignment at their end of the join. It is best achieved by using right-angle clamps at each end to guide the panels into position. Trick: nails are placed in the join to hold the surfaces apart and then withdrawn when the panels are perfectly aligned.

The side joins were firmly clamped and then the top was added and weighted down. The tape is like an impact adhesive so the clamps and weights could be removed and the pedestals carried to their final positions once the tape was firmly embedded.

Disclaimer: Don't try this at home! The result is "good enough" for compressive loads but it is not intended to be as strong as a glued join and is certainly not suitable for cantilevers, as bravely demonstrated below.
picture of a cat on a dangerous shelf

Update: 1st Sept. 2020

I am currently setting up this installation again, this time at the Galerie Meinblau Berlin.
We assembled two pedestals, as described above, but using wooden clamps. They started coming unzipped after they had been moved into position, something that hadn't happened before!

Why? Three possibilities:
  1. the old tape leaves a weak residue which fails when a new join is made.
  2. The floor was uneven so that one side and the front were standing on the ground leaving the other side hanging unsupported over a shallow cavity in the floor.
  3. More likely: I was not using the Swiss clamping power to be seen in a picture above.
Next day:

We cleaned off the old residue with a scraper and re-did the joins, first with Tesa "Extra Strong" double-sided tape and when that worked OK, we used Tesa "Universal" (normal) double-sided tape which worked well too. The pedestals were then moved into position. We used two strong steel clamps to compress the joins.

After the exhibition was over:

When taking the pedestals apart it was difficult to separate the "Extra Strong" joins! So Tesa "Universal" double-sided tape is evidently strong enough.

Three Tempos in Meinblau
Three Tempos as installed in the Meinblau gallery in Berlin, 2020
with a diagram by Tom Johnson projected and traced onto the end wall.

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