View Full Version : New Plasma Cutter
06-15-2009, 02:57 AM
Hi, new to plasma cutters - just got a 60a and had a question. How close do have to hold the torch to start the arc, and then to continue the arc? With this one, I have to practically touch the metal, if not touch it to get the arc started, and if the torch wanders more than about 1/16" away from the metal, the arc goes out. Is this how all plasma cutters work, or might there be something wrong with this one? Thanks!
06-15-2009, 09:57 AM
Sounds like something is wrong to me. I only have a small plasma, but I can keep an arc going from maybe 1/4 inch if I am properly grounded. I do need to be a bit closer to get it going. And there is no way that I could keep my shaky hands within 1/16 inch while making a cut.
You didn't mention whether or not you were getting an easy, clean cut once started. I know that mine will "arc" but not cut much at all if I fail to have a good ground -- I know this cause sometimes I forget to get it attached when I switch pieces.
Try grinding a nice clean spot on piece being cut and attach ground there -- mine does not work well with ground just attached to the cutting or welding table.
06-15-2009, 10:03 AM
First and foremost, you need to provide all the details. What machine are you running, what are you cutting, what amperage are you running, does your machine have a pilot arc feature, etc. etc. etc.
06-15-2009, 01:03 PM
There are quite a few varieties of plasma torch starting circuitry. Provide detail.....make, model number, torch....maybe even some pictures and we can help you out.
Some plasma's are of a "scratch start" design (has to touch the plate)......some use high frequency only (has to be very close to the plate) some have both high frequency and pilot arc (will fire in the air)....and some use no high frequency but have a pilot arc (will fire in the air).
Which did you buy?
06-15-2009, 02:05 PM
That "60a" machine sounds like the typical operation of the china boxes. All I have heard of and seen including the "50A" I own has a HF start (just like some TIG welders). They tend to have a weak HF so you need to touch or almost touch BARE metal/material. This will get the arc started and then it cuts. If you pull the tip to far away you will lose the arc so you need to keep it close/touching.
Push the trigger with the tip far away from metal and see if you can hear a clicking buzzing sound. DO NOT stick the torch near your head to listen. If you hear a buzzing then it is HF start.
Other machines like my Linde 50A has pilot arc HF. When you pull the trigger, a plasma arc is seen at the end of the torch. With that torch there is a stand-off so that the torch does not touch the metal in order to cut. The plasma arc starts the cut and then the ionized air keeps the arc path flowing. With that machine you can cut through paint and other stuff. Bare metal/material is not required.
It sounds like you have a generic China made "60A" model.
06-24-2009, 12:45 AM
Would make life so much easier if people "try before buy"