Do you think this will work?

Archiver

Hi Group

I have never played with a Basic Stamp before but think it might be
just the ticket for a problem I have. I am just nearing the end of
building an X-Y gantry to use for plasma cutting. The last piece I
need is an automatic height control. What some of the big torch
companies do is measure the arc voltage and adjust the height of the
torch with a stepper to keep it in the desired range. I think that
the stamp with an A/D convertor should be able to measure the voltage
(max 335 volts so it will have to be run through a divider) then send
pulses for step and direction to a stepper driver board.

Do you think this should be a problem?

Thanks for your input

Ron

Archiver

Hi Ron,

I already have one based on the stamp. Been using it for 6 months. There are
a few things to keep track of, like the High Frequency starting voltage on
some older and high power plasma cutters.
I have used Stamps for interfacing all sorts of CNC's to all sorts of Plasma
and Flame cutting machines for a few years.
Maybe I can help you,

Alan Bradford
Plasma Technologies


[noparse][[/noparse]Non-text portions of this message have been removed]

Archiver

Alan & Ron,
I have been planning on building a stamp based x,y for my Hypertherm 350.
Problem is, I can't seem to get a vertical kerf. I have seen some of the
high grade commercial machines that leave a beautiful, square edge. Is this
machine worthy of such a project? Any information, regarding this project,
that either of you are willing to provide will be appreciated greatly. I am
starting from scratch and would hate to beat the same dead horse you two
have already conquered. [noparse]:)[/noparse]


Jeff

---

Original Message

---

From: <plasmastamp@a...>
To: <basicstamps@yahoogroups.com>
Sent: Sunday, August 19, 2001 8:09 AM
Subject: Re: [noparse][[/noparse]basicstamps] Do you think this will work?


> Hi Ron,
>
> I already have one based on the stamp. Been using it for 6 months. There
are
> a few things to keep track of, like the High Frequency starting voltage on
> some older and high power plasma cutters.
> I have used Stamps for interfacing all sorts of CNC's to all sorts of
Plasma
> and Flame cutting machines for a few years.
> Maybe I can help you,
>
> Alan Bradford
> Plasma Technologies
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>

Archiver

The stamp does not have the horsepower to control the X-Y functions of the
machine. The integer math is too slow. Circular cut parts require sin and
cosin functions done at a high speed. The PowerMax 350 will cut 26 gauge
sheet metal at 300 inches per min ( 7.6 m/SEC). A more powerful processor is
required.

I have used stamps to do the Height Control (vertical kerf) and for that it
works quite well.
The Hypertherm 350 does not have a high frequency starter so the voltage
divider filtering will not have to be as drastic as with a Hypertherm Max 200
or Thermal Dynamics Merlin plasma cutter.
These big monsters need lots of filtering to prevent the starting voltage
from getting in to the Stamp. This voltage is typically 10,000 volts @ 2-3
MHz. It will couple into shielded cables and give false readings and even
burn out components.

If you wish to e-mail me direct with contact information I will do what I can
to assist you.

Thank You,
Alan Bradford
Plasma Technologies






[noparse][[/noparse]Non-text portions of this message have been removed]