Centroid Community CNC Support Forum

cnckeith wrote: ↑Thu Jul 21, 2022 12:23 pm HD monitors for $99 bucks on amazon. https://amzn.to/3znpfEt

I got this monitor and it is working well. It should be noted though that it doesn't have VESA mount capability.

Build update: Report attached

I have Auto Homing and Axis Squaring working. I did add a Z-axis home switch and started using soft limits all around. I'm having a hard time getting the Floating switch touch off to work correctly. The macro runs but I often get different Float Switch Z zero offset values when I run it. They mostly range between 0.174" and 0.183". I suspect that the mechanical micro switch is cheap and not repeatable. I have a new one on the way. During all the messing around with the float switch I've also found that the gantry isn't parallel with the water pan bed. In the X direction it is off by .102".

landmark573 wrote: ↑Mon Jul 25, 2022 4:35 pm Build update: Report attached

I have Auto Homing and Axis Squaring working. I did add a Z-axis home switch and started using soft limits all around. I'm having a hard time getting the Floating switch touch off to work correctly. The macro runs but I often get different Float Switch Z zero offset values when I run it. They mostly range between 0.174" and 0.183". I suspect that the mechanical micro switch is cheap and not repeatable. I have a new one on the way. During all the messing around with the float switch I've also found that the gantry isn't parallel with the water pan bed. In the X direction it is off by .102".

yeah looking at your video there is a huge amount of deadband from the time the torch hits the metal till t he switch triggers/clears.

Build update: new report attached.

I did a lot of testing today and came up with Float Switch Z zero offset that made sure the WCS Z zero would not be set below the top of the plate when piercing. It could end up as much as 0.020" above the plate. I figured that would be better than dragging the plate around. The goal was to be able to make a cut without crashing. It is just a hack until I get my new float switch mounted. I made a couple of cuts using the Centroid_4inch_line_test file. See the two lines on the bottom.
Happy with those cuts I decided to try the Centroid_Test_Hook file. The video is on my YT channel.

https://youtu.be/ubNh9hPiKG8

There were some problems that you can see below. The holes are there but didn't cut well. It's also not cutting the curves all the way through.

What software are you creating the g code cut file with? All your curves seem to speed up too fast for your machine/power. That’s why it’s not cutting through. Small circles should be slowed to about 60% feed rate. What plasma cutter are you using?

I'm using the test files included with the CNC12 install. They were created with Sheetcam. My plasma cutter is an Everlast 50s with a PT-60 hand torch. I've attached the .tap file here.

Sorry, I should have been more specific, have you created any files of your own to test cut? Circles? Squares? I see those are the stock files from Centroid.

Do you have smoothing turned on in the profile manager? I'm only familiar with my Hypertherm and not sure how your plasma behaves with the Acorn plasma hardware and settings in the profile manager. The settings in the profile manager are Hypertherm's "book" numbers, I don't know if your machine will cut at those numbers or not. Is the target voltage you see while cutting match the profile manager? You may have to experiment with each metal thickness you intend to cut and dial in your own numbers for your plasma cutter.

I have an Acorn controlled CNC mill that I use Fusion 360 for CAD/CAM. I would like to use it for the plasma as well but can't find a Centroid post processor for Fusion 360. So I haven't generated any gcode for it yet. My plasma cutter has a voltage divider output. Can you monitor that with a DVM to check the output voltage?

I am using a Steel 45amp, .250 profile that I modified the cut speed and pierce delay. Smoothing is enabled.

I don't have the Centroid THC hardware yet but intend to get it if this table is any good. I have also intensified my search for a Powermax 45XP,65, or 85 but they always sell for crazy money. Plus the ones I've seen at auctions usually set up for hand use and not CNC.

No THC? This makes more sense now. I've never run a plasma without one so I may not be much help with that.

I've been using the Vectric software for creating the g-code for my parts. I use it for both of my routers and didn't want to learn another program just yet. My plasma had a WinCNC controller on it when it was purchased and I took that post processor and modified it to work with the Acorn and the Vectric software. So far so good. I'm tweaking it regularly and adding features.

I keep playing with Fusion in my limited spare time and may start using it one day.

You can monitor the divided voltage output with a DVM. If the target voltage for the material you are cutting is say 135 volts, just divide that by the ratio your voltage divider is set at. Hypertherm comes out of the box at 50:1 so it I divide the 135 target volts by 50 I get 2.7 volts. Your DVM should read 2.7 volts. Anything else and the torch is too high or too low. When the arc starts the voltage will read very high during the pierce and then settle in very quickly once it starts cutting.

4 inch Line test cuts don't look to bad. Hard to tell if your moving to fast without seeing the bottom of the cuts. Id try slowing the profile federate down some. Also looks like your pierce delay is longer than it needs to be. Should get better cuts with finer tuned federates. Also make sure you have a good clean work clamp connection. That material doesn't look very conductive.