Re: [CAD_CAM_EDM_DRO] Re: CNC and Welding Polyethelyne

Bill Higdon wrote:

>Hans,
>I remember watching somone hand weld up a Poly RV holding tank many
>years ago, the gun used a hot air blast and a rod of the same type of
>material as used to make the tank.
>

(snip)

I have used some of those "hot air guns" for doing that on Auto body
parts. The problem is that it takes way too long to heat up both the
plastic "Rod" and the surrounding plastic so that it actually "Welds"
the parts together.

So, on a CNC machine, I see this to be an additional challenge.

I know longer use the heat gun at all, but rather a small jewelers torch
aimed directly at the "crotch" of the surfaces I am welding together and
the "Rod" I am adding. In this case, I am assured of a good weld no
different than obtaining good penetration when "Gas" welding with a rod.

What came to my mind IF this was going to be a CNC application, was to
consider that "Water Plasma" device talked about earlier for the Flame
Source. It might allow you to make very accurate "Heat Adjustments" as
compared to what is available with a simple torch. Then all you need to
do is to "Spool" in a proper amount of Plastic via Software control,
along with the Axis moving. This way, everything is adjustable. When I
say "Spool" in plastic, Imagine your Weed eater spool snapped onto a
stepper motor forcing the plastic down a ceramic tube to the joint. If
you want to "Add" more "rod", just move the Spool motor a smidget faster
than gantry speed !

Sounds like a cool CNC project and very possible if just to join
straight joints. Other than that, it may get interesting !

Chris L