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Dot Punch: Difference between revisions

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=====Description=====
=====Description=====


[http://wiki.dtonline.org/index.php/File:AutoDotPunch.png '''Dot Punches'''] are similar to '''[[Centre Punch|Centre Punches]]''' but have a sharper point by being ground to an angle of 60 degrees ''(in a similar manner to a '''[[Scriber]]''')''.
[http://wiki.dtonline.org/index.php/File:AutoDotPunch.png '''Dot Punches'''] are similar to '''[[Centre Punch|Centre Punches]]''' but have a sharper point ground to an angle of 60 degrees by holding it '''[[Tangents and Normals|Tangentially]]''' to a '''[[Tool Grinder]]''' and rotating it. This tends to create grinding marks which run along the point and strengthen it rather than weakening it by going across ''(i.e. in a similar manner to a '''[[Scriber]]''')''





Revision as of 09:33, 9 February 2017

AutoDotPunch.png


Description

Dot Punches are similar to Centre Punches but have a sharper point ground to an angle of 60 degrees by holding it Tangentially to a Tool Grinder and rotating it. This tends to create grinding marks which run along the point and strengthen it rather than weakening it by going across (i.e. in a similar manner to a Scriber)


Features and Uses

Dot Punches are held at an angle to the intersection or line to be marked and either lightly struck once with a hammer or, alternatively, Automatic Dot Punches are available, as shown, which are simply pushed down to activate.


CentreDotPunching.png

Note:

If Dot Punches are used to mark where a large hole crosses each of its centre lines, for instance, accurate work would result in each ‘dot’ being halved across its diameter.


DT Online Buyers' Guide

The lowest cost option is to use a hand-held punch with a hammer but a wide range of automatic punches are available - both Dot Punches and Centre Punches.

  • In general, Dot Punches have a sharper point (i.e. 60° instead of 90°) and need only the lower ranges of impact force (e.g. 20N to 50N).
  • Automatic punches are simply pushed down against the work-piece and do not need to be struck - indeed, should NOT be struck with a hammer.