An idle thought...

[Allen Smithee]

Whilst musing in the shower this morning I wondered if it would be possible to use a boring head "backwards" - ie with the cutting tool facing inwards to cut a spiggot rather than facing outwards to bore a hole.

Why? Well I wondered if using a boring head in a mill might be another way of machining crankpins than using an offset fixture in a lathe. It would also be a reason for fitting that reversing switch!

Has anyone ever tried using a boring head in this way?

AS

[Jasonb]

Done it several times but with a tool ground for outside diameters. A lot of the smaller imported boring heads screw onto the arbor so not advisable to run backwards.

Here is one I did a few weeks ago cleaning up the OD of the flange



Often use it to tidy up the cast valve guides on heads so the spring seats true

[Graham Meek]

As Jason says, I too have done this operation on more than one occasion during my profession years and recently in my workshop. Fortunately the gear cutter was one of my standard cutters, I just had to make a new boring bar to hold square HSS.

My best regards
Gray,

[Allen Smithee]

Interesting - many thanks, chaps!

AS

[sshire]

Allen
Here's another. Opening up the furnace casting on the Rider Ericsson to accept the hot cap flange.

[dieselpilot]

It's quite common in production. Some setups will use more than one tool at a time, ID and OD, some interpolate to finish an OD.

<a href="https://www.youtube.com/watch?v=Ocy-Q81VJBE" target="_blank">http://www.youtube.com/watch?v=Ocy-Q81VJBE</a>

Greg