After more than a year away from hobbies, I am back! In meantime we moved into a fabulous house, with 2 workshops! One for wood, in the garage, the other in the basement for electronics, models and machining. Pretty close to utopia for me.
First some catch up from July 2014. Having made the cylinders and pistons, the next item is the cylinder block. A nice chunk of brass was squared up with a 3/8” end mill and then marked up for the center of the combustion chamber. The block was then centered in the 4 jaw chuck and drilled out. I started boring the hole larger but the boring bar has the wrong back rake for brass, resulting in a mess! I left things here as we were packing up the condo in preparation for our selling it.
Rolling forward to the present:
Having access to all my tools is so empowering. I made a new HSS boring tool with geometry to suit machining brass. This solved the issues I was having while boring out the cylinder block to fit the glass cylinders. They are a somewhat lose fit to allow the Loctite 603 to do its job, and to prevent the block from cracking the glass once it heats up during operation.
I also bought the rest of materials that I needed for this project. The supports were not the same width so I fly cut them to be the same. The usual mess of chips flying everywhere but they are now within .002” end to end. Due to the small work envelope I had to shift the pieces 3 times to machine the entire 6.2” length. Thanks to the very solid milling vise this works out well.