Re: CNC Plasma cutter

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Hal Eckhart <hal@c...> wrote:

> On 9/23/04 1:41 AM, jfglass2001 wrote:
>
> >What does a THC accomplish?
>
> It keeps the torch at an optimal height for both starting the arc

and

> cutting (usually different things - which depend on the plasma unit
> you're using). If you try to strike an arc with the torch too high,

it

> won't do anything but make noise. If it's too low, the nozzle gets
> trashed and it may run into the workpiece which throws everything

out

> of whack.
>
> A THC also allows you to cut material that's not entirely flat.
> Probably less of a concern with smaller pieces.
>
> Yes, it does make things nicer. But if it doesn't fit your budget,

then

> don't sweat it. You can always upgrade later.
>
> Hal Eckhart - Casa Forge - Minneapolis MN -

<http://www.casaforge.com>


In this case, I would follow the word of expericance.

My local sheetmetal shop has an older unit that has a large steel
ring that rides the metal. It has a 45 degree angle on it with a 4
inch dia around the tip and a 8 inch OD of the flange. Since they
cut mostly 28 ga sheetmetal, the heavy ring holds the work down to
maintain height.

If you are designing, considder looking at what it would take to
upgrade at some future point and leave mounting holes or whatever to
allow that to happen.

Dave