It's to grip the column on the mill as part of a stop-the-head-rotating endeavour. So I reckon it's gotta be pretty close.I knock the sides off the teeth slightly on a bench grinder if I need to make a holesaw a mm or so smaller.
Depends what it's for, different people have different ideas of accuracy...
It's to grip the column on the mill as part of a stop-the-head-rotating endeavour. So I reckon it's gotta be pretty close.
I would be happy to do that for youAsk Doubleboost to do it and a video at the same time.
I would be happy to do that for you
Plasma then lathe
Nearer to 0.5You're a toff John. How accurate is that cnc plasma table of yours ? 0.10mm ?
That's very kind, John - thank you. I'm going to have a shot at it to see how much of a hash I make of it (worst case is I chop the 100mm off the end - got plenty material!) and might come back to you once I realise it's beyond my abilitiesI would be happy to do that for you
Plasma then lathe
Be sure to scribe the 90mm circle before you drill the middle out.Use a 3 1/2" holesaw which is 89mm then just stroke it out to size with a half round file or even a flap wheel in a die grinder or drill. I've used this method quite a few times, with a little care you can get very accurate results.
Of course, its basic metal working didn't think i needed to mention it.Be sure to scribe the 90mm circle before you drill the middle out.
That was my thought!View attachment 194164
Why would you make a hash of it using a boring head, might be slow, but will give you an acurate circle. Unless you try these widgets out, you wont develop the fonfidence to take on more complex things.
These pictures are before and nearly done.
View attachment 194163