A Quick Change Toolpost
In production engineering anything that can save time or an operation also saves money. In model engineering it does not apply as rigidly but where it can be applied it can pay dividends in time. We all use these shortcuts whether we realise it or not. Using one item to drill another one from is jig drilling, a common production practise. When a few years ago I made the transition from playing to working I looked at ways to speed up simple jobs on the lathe, especially one off jobs that cannot be set up for production i.e. just about every thing that the model engineer does. One of the first things that I looked at was the toolpost and tool setting. As my Myford lathe had a single bolt toolpost and my others had four turret posts I was able to compare them well. The single bolt toolpost had the one main disadvantage of having to change tools and set up every time. The Myford floating boat idea is a good one but limited to Myford tools. The four turret tool post has obvious advantages but it also has a few disadvantages, often when doing internal work i.e. boring and internal screw cutting you are often limited to only two tools to avoid fouling either the chuck or any tail stock operations that may be in use. Another disadvantage on the Myford is that only 3/8″ square tools may be used because of room available. Any resharpening done on either set-up requires the tool to be repacked to its correct centre height. This led me to look at the idea of a quick change tooling system where the tools are always set in a holder and if any adjustment or change is to be made it can be done easily. Two main disadvantages are obvious to this system,
- [a] The cost, these commercial tool holders are expensive and are probably beyond the reach of many.
- [b] They usually only come with three or four tool holders one of which is usually a boring tool holder which limits the use of them to about the same as a four turret post.
- The Toolblock Figs, 4, 4a, 4b,
- The Front Wedge Fig , 2,
- The Side Wedge Fig , 3,
- The Toolholders Figs, 5, 6, 7,