Re: [CAD_CAM_EDM_DRO] Accuracy of CNC Mill

One trick I used to bore a parallel hole was to use a single point
boring tool held in a collet chuck. The tool was moved in a shallow
spiral to bore the hole. With this technique the tool loading is the
same all the way down so you don't end up with a tapered hole. The
finish was pretty good and the hole was within about 0.0004 diameter +
ovality. It was quite slow and I needed to creep up on the finished
diameter, taking a number of cuts to reach the diameter I wanted.

I really must make an adapter to fit my boring head on the CNC...

Les

Polaraligned wrote:

>Can a CNC Bridgeport replace some basic lathe functions such as
>cutting a bearing pocket for press fitting the bearing? Or are they
>not accurate enough. My encoders will be high resolution (1000/4000).
> What kind of overall accuracy can I expect?
>I remember bringing a part to a machine shop about 15 yrs ago to
>have a 5" hole bored in it. It was too big to put on a lathe.
>The machinist used a CNC Bridgeport (I don't know what model) to
>bore the hole with a endmill. The results were not very good. The
>cut was very wavy and I would only call it a rough cut. This appeared
>to be the limitation of the machine. I needed to use a boring head
>on my home mill to make the hole round.
>I know technology has come a long way since then.
>
>Any comments appreciated.
>
>Thanks,
>Scott
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