Had to check a few things in the shed yesterday. It was hot! In fact too bloody hot to do any work.

38 deg is just a tad too warm for me to do any shed work these days.

Today was much milder and I was able to finish the sanding of the horizontal stabiliser with 120 followed by 240 grit.

I also put some epoxy filler on a few spots on the top side.

Unless Laurie wants to go to 400 grit I think that’s the sanding done, ready for spraying the top coat next week.

Here is the mud map for the new luggage shelf.

The battery retention will be designed for 20 G per GFA BSE. For the envisaged 12V 7AH battery at 2.2 kg, the installation needs to withstand a force of 44 kg in the forward direction. After removing the inspection hole cover at the back of the luggage compartment I found that there is already a triangular frame which can support that load..

Regarding the battery selection, I’m working on the basis of using the oldfashioned sealed gel type used in most gliders rather than a LiFePo. Might sound odd coming from an EV driver (the MG4 has a 400 kg lithium battery pack), but it’s from knowing the complexity of the battery management and safety system in EV’s that I’m hesitant to suggest a lithium one for the Bocian which would not have the same safeguards as an EV.

KYU is wired for 2 batteries, with a selector switch on the front panel. I suggest to have just a single battery to a) save some weight in the luggage bay, b) avoid having to design the shelf for 88 kg force and c) to avoid potential problems with the electrics for a dual battery setup (cell balancing etc.). We’ll have to provide a fuse/circuit breaker at the battery, as well as a different plug/socket setup. I don’t like the recessed open type of socket currently fitted, which runs the risk of shorting by metal objects or spilled liquid, e.g. from a water bottle.

I also believe the ability to remove the shelf will prove advantageous for easier inspection and lubrication of the aileron and airbrake bell cranks and associated push rods located underneath the shelf.

The antenna will be relocated to a position where it will no longer rub on anything below the shelf. To fit the new frame, the aluminium sheet ground plane for the antenna will be slightly larger, which should if anything be beneficial.