Re: Oxy-Fuel Piercing - How much to tilt from 90 degrees?

Thanks Les!

Exactly what I was looking for - someone familiar with how it is
really done as opposed to me guessing.

The preheat is very efficient and I can get a fairly sizable area
ready for the cutting oxygen and then move across it in one of the
patterns you suggest.

The approach you suggest - i.e. moving, while initiating the cut
comes close to replicating the geometry of a tilt.

I'll keep you posted on progress and thanks again.


Bob


--- In CAD_CAM_EDM_DRO@yahoogroups.com, Leslie Newell
<les.newell@...> wrote:

>
> Hi Bob,
>
> Before going to the hassle and expense of setting up a fourth axis,

try

> a couple of alternative piercing strategies:
> Wiggle or zigzag pierce. Keep the torch moving back and forth over

a

> small area. Any blowback will come out behind the direction of

movement.

> This is popular with waterjet cutters which have similar problems

with

> blowback.
> Ramp pierce. Similar to the wiggle pierce but lower the torch from
> preheat height to cut height while slowly moving along the lead in.
> Again any ejected material will come out behind the direction of

movement.

>
> Both of the above strategies allow you to pierce at any angle while

a

> tilting torch has to pierce at the same angle as the torch tilt

unless

> you can tilt in both axes.
>
> Les
>
>
> jacoby01 wrote:
> > Does anyone have experience with a tilting head oxy-fuel CNC

setup?

> >
> > I'm designing a head for my Harris 98-6 machine torch (oxy-

propane).

> > It is a high speed cutting torch (20 ipm through 1/4" steel) and

I'd

> > like to design a tilt feature into the head mount so that slag
> > doesn't clog the 6290-VCC tip when I pierce. According to the
> > pictures that Harris publishes, the quality of the cut is

incredible,

> > but you've got to keep the tip clean during piercing.
> >
> > Most likely I will build in both rotation - up to 45 degrees from
> > vertical and torch height control (the THC is mostly for the

plasma,

> > but if I cant the oxy-fuel torch over to 45 degrees from vertical

I

> > would most likely have to lower the torch in the same macro).
> >
> > Most of my cutting will be done in 1/4" to 1/2", but I have
> > aspirations to cut up to 4" on some projects.
> >
> > So the questions:
> >
> > 1) Does anyone have experience with this kind of setup and any
> > recommendations / suggestions as a result?
> >
> > 2) How much should I tilt the torch from vertical so as to not to
> > contaminate the tip?
> >
> > thanks in advance for any suggestions.
> >
> > Bob in Florida
> >
>