I thought that some may be interested in our process in the workshop. Here is a brief description on how we make the wooden bases. This weekend I have made a start on two 10" Walnut bases, one is to be round and the other square. They are both for Inner Planet Orreries that I hope to complete by the end of March.
You may have noticed the way we make our bases is in sections rather then turn from one solid slab of timber. This is to prevent the inevitable rough end grain from appearing on two opposing sides of the base. It also gives the grain on top a nice pattern encircling the orrery.
I put this job off last week because the Mitre Saw is set up in the shed and it has been very cold out there. I bravely got to it on Saturday, first chopping six blocks at 30 degree angles for the round base and four pieces at 45 for the square.
These are only rough cuts, it is vital that each block is machined flat and parallel with each face perpendicular to the next. This means using trigonometry to set up parallels on the mill bed.
After all five faces are machined it was time to glue the blocks the together. I applied PVA glue to the edges and held them tightly together in our purpose made vice. The blocks went together very well. The pitfalls of not machining the edges perfectly square are gaps showing at the seams which would have meant starting again. Another issues I could have potentially come across would be not having the edges of the square base all meeting at the same distance which would not look right when the bases edges were eventually bought to size.