High Frequency shielding for CNC Plasma

**Gadget** · 06-23-2010, 08:46 AM

]Here are the promised photos of how I shielded my CNC electronics from the high frequency of the plasma cutter. The braided shield was purchased online and the wires were threaded through them. Pretty easy to do, just compress the braid like one of the Chinese handcuff devices you played with as a kid (I'll bet you had one) which makes a large enough center hole to thread the wires in then once over the wire just pull it lengthwise to cover the wire.

Dan

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**weldingtwopotatoes** · 06-23-2010, 12:20 PM

Thanks Dan for the detailed photos they will definitely help me with my build. On a side note how are your rails constructed? I can see that it is a piece of galvanized pipe sitting on top of a piece of channel but how is the pipe attached to the channel?

**Gadget** · 06-23-2010, 05:46 PM

For the Y axis there are quarter inch threaded rods going through the main beam into the bottom of the tubing. Each main beam has 1.5" holes running through the beam, the 1/4" threaded rods goe through the beam into the 1.5" hole. There is just enough room to put a nut on the rods and snug them down in the large hole.
For the X axis there is only a tube at the top of the beam so the threaded rod goes in from the bottom of the beam up into the tubing.

**Arcamm** · 12-07-2010, 10:40 AM

Hey Gadget, any chance of getting your photos re-posted? I'm talking with a guy who builds cnc router tables about building one for plasma. He's not familiar with the requirements for plasma cutting and electronics protection. Any info would be helpful.

**Gadget** · 12-07-2010, 12:52 PM

Photos are reloaded

**samsberr** · 12-07-2010, 01:00 PM

Good Post...
Very Informative...
Thanks

**Charley Davidson** · 12-07-2010, 01:54 PM

Seems like a lot of work, Think I will stay away from high frequency plasma cutters for my future CNC table. For using non CNC I'm sure it would be fine.

**Gadget** · 12-07-2010, 02:41 PM

My feeling is it is the arc start and stop that causes the issue with my CNC table. I use pilot arc to start my arc but before shielding if it sputtered or quit cutting for any reason it would lock up the steppers.

**Arcamm** · 12-07-2010, 06:20 PM

So you need the shielding even with a pilot arc torch?

---------- Post added at 08:20 PM ---------- Previous post was at 08:19 PM ----------

Oh! And thanks for reposting the pictures.

**KHK** · 12-07-2010, 10:55 PM

From my experience you do not need to stay away from high frequency. You do need to do the shielding. On my CNC ALL wiring is in shielded cable. ALL the shields are grounded in one point like a spider web, with the ground in the center of the web. The control box holds ALL electronics and is isolated from high frequency via a ground.