Thanks for responding, Trent.
All of this is very interesting to me. My questions have been posed because
someday, I
will have all the drawings and information necessary to build my loco (SP18) in
quantity. The methods of manufacture available, their tolerance, and cost would
determine how feasible such a project would be. Thanks for the perspective.
royce
Trent Dowler wrote:
> Hello Royce and all,
>
> At our shop we have "Bubba", who is pretty good with a torch, but his accuracy is
> +/- "aw, about so much" and not very fast at that.
> Depending on the erosion rate programmed, our wire EDM can hold +/-.0001" tolerance
> without a problem. Our sinker type EDM can hold about the same tolerance. Both
> machine's accuracy depends solely upon operator experience (and other factors that I
> won't get into here).
> We do not have a laser, but I have ordered parts that were laser burned and held
> +/- .015" tolerance in .05" thick stainless steel. I would tend to think that they
> are capable of much higher accuracies than that.
> Parts from our oxy/ocetylene burn table are expected to be held within +/- 1/16" of
> size, 1/32" parallelism within 36", and no more than 1/16" kerf in 2" thickness.
> Flatness can also be effected by the heat transferred into the part during the burn
> process. Our most experienced operator in the shop knows how to handle these problems
> before they develope. Good guy to have around.
> For those of you who are not familiar with wire EDM (Electrical Discharge
> Machining), the parts are cut with a thin brass wire that is .010" diameter. It
> doesn't matter how thick the part is, or how hard it is. The cutting is done by
> eroding the part's material away at a VERY controlled rate and position. It still
> amazes me every time I run ours.
>
> Later,
> Trent
>
> Royce Woodbury wrote:
>
> > Salty,
> > The only CNC machining of steel, for example, was done by a EDM machine. I am
> > told they will hold a tolerance of .010, or maybe better. How does this relate
> > to laser or oxy/acetylene accuracy?
> >
> > royce
>
