Author Topic: making fine indexing marks?  (Read 1257 times)

Offline picclock

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making fine indexing marks?
« on: January 02, 2020, 04:14:10 AM »
I need to make some very fine indexing / calibration marks in steel. Ideally the thickness should be about the same as on the half mm divisions on an engineers rule ~ 0.1mm thick.

Does anyone know how this is done ?  My best thought is some form of etching, but not sure how this is achieved. My desperate thought is to butcher a cheapo 6" rule and fit the remains in a recess.

Any thoughts or ideas much appreciated.

Best Regards

picclock
Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline Lew_Merrick_PE

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Re: making fine indexing marks?
« Reply #1 on: January 02, 2020, 10:48:20 AM »
Hi Picclock  ---  There are finely tapered engraving tools with which I have had good results making .005 inch marks for "alignment guides" over the years.  Here in the US they run (about) USD 15.  I probably have 2 or 3 sitting in my "strange bit" cutter bar.  --  Lew

Offline Pete.

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Re: making fine indexing marks?
« Reply #2 on: January 02, 2020, 11:18:35 AM »
I made one in a pinch from a broken carbide end mill. I ground the tip to a fine point then ground one side flat. Made a super-sharp engraving tool.

Offline awemawson

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Re: making fine indexing marks?
« Reply #3 on: January 02, 2020, 11:18:56 AM »
Dip subject piece in melted wax to form a thin layer. When hard index an ordinary sewing needle or pin in the shape of your engraving lines. Dip in the etchant of your choice depending on material of subject.

. . . warm to remove wax . . stand back and admire your fine lines  :clap:
Andrew Mawson
East Sussex

Offline picclock

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Re: making fine indexing marks?
« Reply #4 on: January 03, 2020, 02:39:13 AM »
Hi
Thanks for the interest and ideas. Ideally I would like a bit to fit in the mill as then I can use the scales to get accurate positioning.

I have tried looking for a fine engraving bit but have found none suitable for steel in the uk. Will keep an eye out though as I think this would be a good solution.

I have had an idea which might pan out. By rotating the mill head so the cutter is at 45 degrees I could use corner of a small carbide end mill to cut a V groove of a suitable size. I have a 3mm endmill in carbide and some smaller ones in hss, but the carbide one may do the trick. I'll give it a try and post pictures if successful.

Many Thanks for your interest.

Best Regards

picclock
Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline chipenter

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Jeff

Offline picclock

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Re: making fine indexing marks?
« Reply #6 on: January 03, 2020, 06:41:29 AM »
@ chipenter
Ordered :-)
This is exactly what I was looking for, and at a cheap price too. I could find nothing like it on AliExpress or in the uk ebay, only tools that were for plastic or aluminium.

Will probably try the tilted endmill approach but this looks much easier.

Many thx

picclock
Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline efrench

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Re: making fine indexing marks?
« Reply #7 on: January 03, 2020, 01:37:11 PM »
There is a ton of carbide engraving bits on Aliexpress.  Here's one which has a list of all their 3.175mm shank engraving bits.

Offline RotarySMP

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Re: making fine indexing marks?
« Reply #8 on: January 03, 2020, 03:17:28 PM »
If you don't want to go too deep, then drag engraving works in steel.

Did this in aluminium, but you can see the tool. Just an old carbide end mill ground to a 90° point, and spring loaded.
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Mark
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Offline picclock

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Re: making fine indexing marks?
« Reply #9 on: January 05, 2020, 02:20:06 AM »
@efrench
Thanks, that's an excellent link. I spent ages trying to find something like that on Aliexpress, but failed. I was probably not using the correct search terms.

I did a quick test using a 3/16 carbide endmill on a scrap piece of cold rolled steel held in the vice at 45 degrees, and the result was OK. The metal wasn't square to the Y axis but as the picture shows the lower of the two lines was around the correct width.

Many Thanks

Best Regards

picclock
Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline polecat

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Re: making fine indexing marks?
« Reply #10 on: January 17, 2020, 04:56:45 AM »
diamond engraver tool used for engraving trophys
polecat