Clive, yes I'm sure it would be of interest, particularly to people like me with no formal training or work experience in the field. All the gear, well lots of the gear, but no idea.

Since many of my little jobs are repair/replacement of parts, I've no idea how they may originally have been made. By their very nature they are likely to be one-offs, with no book or magazine articles top provide guidance.

I'm also curious to know which bit you're making yourself; is it the little lever detent arm above the 0-10 scale shown on the photos in this article.?

Bill

Neil, please feel free to move to another thread to save disrupting this one.

I've often found that a good way to come up with a solution, is to chuck a few ideas in the pot and let someone else pick holes in them. So long as everyone plays fair and doesn't seek to cause or take offence, it's worked quite well amongst my various friends and acquaintances.

Here's one, (that I've never tried), using the basics of my own kit; lathe, V.mill, and rotary table (without any dividing plates).

For a photo, click on "2" on my previous link, and scroll down to the 4th photo.

I guess I have the advantage/disadvantage of no training on how one should approach a job.

The intention is to make the gizmo without needing to also make loads of extra jigs/fixtures, and minimise the maths, as not everyone is comfortable with trig tables.

1) Turn the top hat to size on the lathe, index the jaws of the chuck with a suitable stand off from the bed and mark off 2, 3, 4, or 6 lines at centre height using the chuck jaws to divide accurately. (3 or 4 jaw chuck according to how many slots required.)

2) Move chuck to rotary table, standing on edge, on V.mill

3) Mill slots as required, according to previously marked lines, but slightly undersized. (I couldn't easily get exactly the right angles for the sides of the slots due to lack of dividing plates, just the whole degree scales on the periphery of the table. )

4) Transfer back to the lathe

5) Grind and hone a bit of tool steel to exactly the same size/angle as the detent lever, by eye if necessary.

6) Use your new tool, horizontally in the lathe toolpost, again indexing the chuck jaws on the bed, in the manner of a slot cutter to plane the undersize slots to the correct profile and depth.

This should cover most tap, drill, or core drill flutes, but obviously not 5, 7 etc.

You could even try a test piece, and a bit of blue on the detent to see if you've honed the angled tool accurately.

No trig involved, or scope for miscounting scales on New Year's day morning.

Please feel free to pick holes in the above; that way we all learn.

I've just typed it quickly without fully thinking it through. (other than not using machine tools with a hangover of course  

Bill

Edited By peak4 on 30/12/2018 12:19:36

Edited By peak4 on 30/12/2018 12:33:30

A couple of very simple tips for absolute beginers.

On my bigger lathe I have a QCTP and a conventional TP on the smaller lathe.

TIP : My preferred method of setting the tool height is to simply face the work piece, when the small nub has gone tool is at correct height.

TIP : I have lots of cheap feeler guage fingers to allow me to get the tool bang on, I can very quickly shim up a tool to get it right using these for final adjustment.

I have made brass GIB strips for the older lathe to replace the worn steel ones, the carriage is now slop free but movable.

Ian

I just assumed you guys would just cut the slot to width at depth and file the sides to scribe lines…?

..of course if your filing is like mine then without file guides it'd look like my dog has been chewing at it..

pgk

That's rather neat Clive. I like the way you hung the rule using it's hole. Was in Lidl today and they have digital angle gauges at a tenner I think but I prefer things that don't use batteries.

I don't think you can go wrong for a tenner as long as it's accurate enough for the intended use, I will have to take a look around for a Lidel, thanks Bazyle.