gday.

thinking about it for a day and i think ive already solved the problem, but hey...

i have a job that at first glance looks impossible. cant really tell but that hole is hidden under the overhang...

Attachment 242858

i want to spot face/counterbore that hole for clamping down what some people might recognise as a tailstock!

Attachment 242860

yes, i know its ugly. ive just ground away its "make-up" (ever noticed, that unlike cheap machinery, some women look far nicer without that muck plastered all over? )

its lovely what you find in china stuff, isnt it?

any advice or ideas would be appreciated, but im thinking this is the way to do it...

first, clamp the base to the mill table, as thats the only accurately machined surface.

flycut/face the top, the part that obviously has been through a shaper with some really coarse feed...

while im at it, face off that horrible looking unmachined lumpy part so its square too. maybe even run the radius cutter down the edge

then flip it over, clamping it down to the (now parallel) face.

that lets me centre on the hole in question.

then i bore that hole out an extra few mm, just because. only 12mm at this point.

stick a boring bar down through the hole, with an "inverted" tool poked in once its through.

write a simple bit of code with the shapes wizard... basically just use the boring bar diameter as the tool diameter on an internal circle, and chop the resulting g code up a bit,
so rather than rapid downs and so forth, it lifts the tool UP to the spot face, then away i go... nothing fancy, nothing accurate.

the overhang on the tool held in the boring bar will be what cuts the spot face... about 5mm or so i reckon should do it


assuming i bore the hole to 16, that should give me a 25mm or if i really scrape the bar on the hole, 26mm counterbore.


make sense? sound like it will work?

sure does to me im procrastinating, talking it up, rather than doing it.

well, its a good way of getting the procedure down in my head, ok?


im finally making one of those cam action lockers for this thing. hence i can bore that hole out a bit more, but i really do want a nice surface for the cam supporting block to sit on.

pic doesnt do it any justice, but it doesnt really need any...under all that bog is some rather pimply sand casting!


im not going back outside, its too cold. the machine is a "BV20", lil bit bigger than most bench top lathes, especially with the 2hp motor i fitted to it but still a bench top

most useless feature of it is the lack of LH thread cutting capabilitis, ive found so far. and it came with two 98T gears rather than 1 98T and one 105T gear...

the 105 is the most important gear of all!!!!! grrrr. one day ill cut one up and install a reverser too or turn it into CNC...


anyway. procedure is sorted.

ill be back with pics of the result, be they good or be they a complete stuff up!



oh! the name of the thread....i really wonder how brembo manufactures their "monoblock" calipers... gotta be a pretty neat tooling system they have! this is simple compared to that!

Attachment 242862


how do they bore those cylinders from the disc slot?