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PVC collars

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Tom's videos are pretty useful actually - I've been playing with machines for more decades than I care to contemplate but still often find something to learn in his productions.

....but he can defend himself I'm sure . . . after all he is a member here.

Andrew other than the yank bit, which I don't get, I think he's positive about the video, negative about the results of holding drill press work by hand (as is Tom), and using a conventionally sharpened bit on plastic or brass.

I'd disagree with both that "dulling' the bit is what is wanted, rather than reducing the cutting angle while keeping the bit edge sharp.

I usually reduce the angle to parallel with the bit axis, and use a bench stone -- keeping the bit parallel to the corner of the stone over which the lip is hooked. This adds a small edge parallel to the axis of the drill bit, but a sharp edge, not a dull one.

In Tom's video I see a slip used and the angle is varied as he uses it and calls it dulling or chamfering. It does work on plastic, but I think the scraping of a sharp edge (not a sharp angle) is faster and smoother cutting. One Yank's opinion anyway.  :)

Steve, I just wondered what a flat bit would cut like in plastic. I've never tried it but I should imagine some of the better designed ones,like Bahco,would probably do the job quite well.

PS: I also agree with what you're saying about altering the angle but retaining the keen edge.....OZ.

Hi Lads , just saw the comments about drill bits, the bit I used was what I thought was pretty sharp normal type grind to the point bit, I am not sure but this PVC is quite hard but not like perspex hard. As the drill bit goes in the material feels soft and soon the bit is warm and the shavings come out very soft and pliable soon returning to hard again but this might be why I had no snatching ? I was lucky as just thought here is a bit about the size I need , lets go for it  :thumbup: :dremel:
  I would agree with the angle getting altered but keeping the sharp edge if snatching was a problem. From the videos and other info I have seen from Tom, he seems the walk the walk not just talk the talk so I would think his advice will be effective too.

  Cheers Mick.


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