Having given this project some more thought, I decided that the idea of having one plate size capable of taking a range of bearing sizes was too much of a compromise. For my initial expected application, a 20mm boring bar would be adequate. Having a set-up capable of taking a larger bar made the assembly overly bulky.
It seems preferable to have plates dedicated to each bearing size, reducing the weight and clumsiness of the whole set-up.
I’ve redrawn my thoughts, and this is what I’ve come up with.
The basic bearing plate, is now hexagonal in shape. I anticipate welding three tack plates to the job, so it makes sense to use hex plates to simplify this process.
I have also incorporated an extended baseplate on the other end to take the magnetic base of the mag drill.
I anticipate that this plate will be subject to some vibration and flexing. To overcome this I will add side plates, with the dual purpose of adding strength and also providing a more positive location for the drill unit.
When I’ve measured the base of the drill accurately, and produced a 3d model of it I will add it to the drawing, but for now, here’s where I’ve got to.
I show the revised design here, set-up on the arm of my loader project. It should be clear how I anticipate the equipment working. With hindsight, the third tack plate on the drill bearing might be better located of the tail end of the plate under the drill base. However, in practice I guess this would change from job to job.
I’ve revised the boring bar also, using round tooling holes rather than square section. This will save a lot of broaching, and enable me to grind-up my own cutting tools from round tool steel.
Thoughts and comments would be appreciated. 🙂