The final stage of the case sides before fitting is to sheathe the inside of the case. Since there are going to be three epoxy applications per side and the second and third layers need to be applied whilst the prior layer is still chemically active, this is going to be an all day event, sort of. It will be apply the next layer and wait. Repeat three times.
I set everything up yesterday evening and first thing this morning I started.
The first layer is unthickened epoxy spread onto the inner side. This is allowed to soak into the wood for a while before the next layer is applied.
There is a slight wrinkle to this layer in that the aft end has a part that is not inside the case but goes alongside the aft block. This part has only one coat of epoxy and needs peel ply added to remove the amine blush once the epoxy has cured.
Now we wait for this layer to start curing. The stage we are looking for is when the epoxy gets to be about as tacky as Sellotape.
Time for a cup of tea.
Three hours latere the next stage is done.
The cramps hanging down over the edge of the case side are there to ensure that the glass mat drapes over the curved edge of the plywood without any lifting. I have done this to ensure that the edge of the glass mat will be under the bottom edge of the side when installed. This means that when the centerplate is lifted up, there will be no edge of glass mat to catch on the plate and eventually tear off. This way there is just a smooth curve and no edge.
I hope.
Time for a cup of tea.
Finally, for the coating of this side at least, the third layer.
This layer has graphite added to the epoxy, 10% by weight, to form a more lubricating surface. The result is a black epoxy layer which looks really nice to my eyes. Shame it is on the inside and will not be seen when the case is assembled.
I will give it a few moments to level out and then I will wave a hot air gun over the surface to pop any bubbles that remain after the mixing.
This has to be left for 24 hours or so to achieve full strength and then I will take it down to the workshop and trim the edges of the glass mat. After that it will be the turn of the other side.
Time for a cup of tea.