MEW 261 -Mike Cox - Axis Stop bars

This question relates to Mike Cox's "Enhancements to the Sieg Super X1L Mill in November 2107 (No 261) edition of MEW and specifically to Fig. 1 of the part dealing with Axes stop bars.

Don't laugh - but I just wondered how you would machine the rounded end of this piece. Before I got a lathe and a milling machine, I would just have hacksawed bits off and then again the peaks of what was left - in a sort of workshop version of Pythagoras' approach to the value of Pi - and then use a file and emery paper to get the final curve and finish.

I could use a rotary table with the workpiece bolted through the hole (and raised above the rotary table by a thick washer) and just rotate the workpiece around a stationary end mill. But I'm open to better or more correct (in an engineering sense) methods.

.

Sounds entirely reasonable to me, Colin

[you do, I presume, mean to have the end mill rotating]

Two cautions:

1. get the position, and direction of rotation, of the table correct for the cut.
2. don't overshoot the 'end' of cut ... it looks very ugly.

​It would be wise to practice on a piece of scrap material.

MichaelG.

Hi Colin,

My usual way of making rounded ends on bars is to find or make a washer the same width as the bar and bolt this to the bar through the hole in the bar. Then excess material was cut off crudely using a hacksaw as you describe using the washer as a guide. Once most of the material has been removed then use a file or linisher to clean up the profile, again using the washer as a guide.

This is usually much quicker for a couple of small pieces than to set up the mill to do the job.

Mike

MIchael G - silly me - should have said "stationary mill table" rather than "stationary end mill" - bit of a Railway Observer Einstein Relativity moment.

Mike Cox - thanks for assuring me that there is still room for good old physical workshop practices.

Hi Colin,

Another way would be to put the 6mm drill or 6mm pin through the hole and rest the drill/pin on the vice jaws. Set the end of the cutter 12.5 mm above the vice jaws. Now take cuts over the rod bracket. Then it's just a matter of undoing the vice and incrementing the bracket around in small steps. You will be left with facets that will have to be filed off.

Just another way of doing it.

Steve.

I normally use either Michael or Steve's approach.

I've used the rotary table approach for connecting rods and eccentric straps.

Neil

All of the above - plus using a belt sander (with a set pin) to revolve the work. Same kind of idea also works with an emery disk in the lathe or even a sanding drum in the drill press.

Regards,

IanT

With the recent interest in devices for making ball handles, how about making "half a ball" = rounded end stop?

Get writing...

Neil

Thanks for all the good methods. Generally it comes down to whether you are fabricating one item or there is the possibility of having to make many. Belt and rotary sanders I'm quite happy with and have table setups using DIY belt and rotary sanders running with the sanding surfaces vertical when creating the complex curves that my electric guitar body builds require - but the time and effort to set these up is not worth it for just a couple of items. Similarly KWIL's idea is good - except that I haven't got a ball turning attachment and currently see no reason to either get one or make one - this may change.

I know how to do the simple hacksaw, file and finish methods (working in remote places in Africa, South America and Siberia taught me to use whatever was available to construct items) - but for my machine learning phase - I will see how I get on with the rotary table method - with just a test piece to see what the problems and solutions are.

Neil,

Nothing to write up, its all been said already in six words. Make half a ball, but that is only four words.

There was a project in the Oct 2012 edition. ' A Universal Device for Cutting Radii on the Mill '.

A very elegant solution but as you said probably not worth it for just a couple of items.

Having nearly completed my Mill stops "a la Cox" with slight modifications to accommodate my linear digital scale units - I'm now in the DIY market for stops for my Amadeal CJ18A mini-lathe - which is a Real Bull variant of the common Chinese lathe. Can someone point me in the direction of an efficient design within (or without) the pages of MEW - that I can go back to (with my new digital subscription). The Lathe bed has a truncated "V" as the locating position - but that is just a fabrication issue - it's the ease of use and efficiency design that I'm looking for - how easy to re-position coupled with position security. And I'm guessing - looking at my lathe - that a stop that turns off the leadscrew feed is not practical or even sensible. So, as a beginner, I'm again guessing that lathe stops are only used with manual feed of the tool.

Do you mean Lever Carriage Stops MEW 239?

Hi Colin,

I fitted stops to my minilathe and also added a dro, see:

http://mikesworkshop.weebly.com/carriage-dro.html

At a later stage I modified this system so that the carriage would stop moving when it reached the stop, see:

http://mikesworkshop.weebly.com/autostop.html

These pages may give you some ideas,

Mike