A simple tool that I made for long rods that need a center hole in the end of the rod. The hole in my lathe is 1/16" too small to fit the rod into. So, to machine and accurate centering hole for the tail stock, I made a bushing to make the hole and eliminate wobble.
https://www.youtube.com/watch?v=6UKHHgXBVLA
Boy, I am not getting any comments on this tool, so I guess that means that it is either very good, or very bad. LOL.
Hi machingfool
This is a very simple method you have devised to centre drill the end of a bar which is too large to fit up the spindle bore. Especially if you don’t have access to a fixed steady. But if you do have access to a steady this would make this idea redundant. The advantages of a fixed steady offer, one fits all diameters. (within the limits of the steadies capacity). Also any size centre drill can be used as well as other operations such as drilling, boring, internal threading etc. with a fixed steady. Your idea is a clever way to use a bushing and centre drill as a support to centre the work piece to then be supported via a tailstock centre if a fixed steady is unavailable.
The Home Engineer
Your tool works well. I had the same problem a few years ago, 1 inch shaft, 7/8 hole through the spindle, I found an old steady rest for my Atlas at a very low cost and I did the procedure with that. I have to do the same thing but with a shaft that is twice the length of my lathe so I will be making a jig similar to yours and will use a hand drill...
I agree with you, but, assuming one can bore two holes, there is no setup error, as with a steady rest, as the center drill can only drill in one place, the center of the rod. Bob.Quote:
Originally Posted by thehomeengineer
The problem I had was that not only was the rod very long it would not fit through my lathe spindle. The only option was to do the job by hand. So I made some bushings to go into 5C collets which clamped onto the shaft.
https://youtu.be/fsG7U7fkvdI?si=3Hd5jfoz_lOSkktQ
Very good method. It works. Also with my simple bushing, a center hole can also be drilled by hand on the end of any rod. Bob.
Thank you for the reply. If the work piece is not centralised in a fixed steady this is very dangerous as the steady can easily work the workpiece out of a tighten 3 jaw chuck. So the workpiece has to be concentric to prevent this from happening. I have seen a couple of accidents where people have not understood how to use a fixed steady. The method you propose is perfect for materials which are not suitable to be supported via a steady in the first place, materials like raw cast-iron, non concentric material or materials with a poor surface finish and only need external work. Even then in most cases the end of the stock needs to be faced to create a datum or just cosmetic reasons, which is difficult with a centre in place. These materials once centred using your method can be supported via a centre and the outer diameter machined concentric to then be supported by a fixed stead. I am not saying your method doesn’t have a place but it does limit the component being made, to only be machined on the outside diameter due to the centre supporting the material.Quote:
Originally Posted by machiningfool