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simonl
8th Apr 2020, 07:09 PM
From time to time I have reason to cut an internal keyway.

Eventually a job for my shaper but it's still in pieces so I do them on the lathe.

A slow painful process and not particularly good for the lathe.

However, this time I pre-drilled a hole which removed about 70% of the material.

So I needed an 8mm Wide x 4mm deep keyway in a 35mm hole.

On the mill I drilled a 7.6mm hole at 17.5mm out from the centre.

Then onto the lathe for boring out the 35mm hole and cutting the keyway.

The pre-drilled hole reduced the time by about 75%.

Also, the pre-drilled hole acts as a chip breaker so no need for a run-out groove.

Much easier!

Sjmon

https://uploads.tapatalk-cdn.com/20200408/cc0bf703ea86615b95ebb6fea60046a0.jpghttps://uploads.tapatalk-cdn.com/20200408/6e956c0fed5b5b23c865158ead2fd048.jpg

Sent from my SM-G970F using Tapatalk

BaronJ
24th Apr 2020, 12:03 AM
From time to time I have reason to cut an internal keyway.

Eventually a job for my shaper but it's still in pieces so I do them on the lathe.

A slow painful process and not particularly good for the lathe.

However, this time I pre-drilled a hole which removed about 70% of the material.

So I needed an 8mm Wide x 4mm deep keyway in a 35mm hole.

On the mill I drilled a 7.6mm hole at 17.5mm out from the centre.

Then onto the lathe for boring out the 35mm hole and cutting the keyway.

The pre-drilled hole reduced the time by about 75%.

Also, the pre-drilled hole acts as a chip breaker so no need for a run-out groove.

Much easier!

Sjmon

https://uploads.tapatalk-cdn.com/20200408/6e956c0fed5b5b23c865158ead2fd048.jpg

Sent from my SM-G970F using Tapatalk

Hi Simon, this picture has the effect of an optical illusion ! When I first looked at it I couldn't understand why there appeared to be a pin in the bottom of the slot, then suddenly it became a drill hole. Weird. :oo: