Hi so when i use the Dynatorch with the THC it starts a cut moves a few inches then stops. I can only get it to work if i turn off THC and stop on no arc. I understand these must be switched back on when im done and that THC off will likely create greater wear on my consumables ( i use my own). The ohmic sensor still sets its height automatically but if there was great variation in level it would certainly drag. It works fine without it but its a cool feature that i would certainly like to be able to have on. I notice the contact ring on the ohmic sensor very lightly touches the nozzle shroud. could creating a better contact help this. Thanks.
The other day i was waiting on the dynatorch as the class on it was wrapping up and they were having similar issues. I talked with the instructor some and we couldn’t figure out what was the problem. so we tried cutting my parts instead of the DMS logo. For whatever reason, my parts cut just fine, along with the next guy to use the machine. I dont have an answer for you, but thats what i saw happening.
THC? drag?
There may be people coming here looking for
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i believe this other guy was me you were cutting the light bar brackets?
You are correct, sounds like you are the other guy. congratulations on your new name, lol.
We are making more checks today. This includes checking the grounding rod resistance.
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There is a ton of slag on the slats where most people put their projects to cut on the bottom right side of the machine, i wonder if thats causing grounding problems.
I’ve gotten some better results when I take a welding hammer and knock a lot of the dross off, or use the left side of the table. However I’ve still seen it play weird even if I grounded directly to the piece though it seemed more reliable, so I think it may be the grounding rod as well. Would explain the kickback that’s repeatedly killied our ohmic isolators.
We are planning to get a proper crash cart, so it will be easier to work with each area of the machine.
-Jim
Unfortunately I was not able to test the grounding rod today. Nacho was having a class & then someone was smithing.
Is the table currently useable? When I came in a few nights ago it would not home. I was there when another user came in and after a few minutes told me a lot of the setting (numbers) were wrong then he put a sign on it. I’m heading up this evening because I need to make some cuts.
we homed the table tonight after some adjustments; it was triggering a motor over current at a certain point when returning to home if far enough on the table. We turned down the motor acceleration on the x axis to mitigate this until we can check the drives in a bit more detail to see why it’s happening, possibly some debris in it.
We also ran a test on the ground rod, and found that there was a 1.45 VAC difference going to the hypertherm; this is about a volt higher than it was supposed to be. After some diagnostics we found that the hypertherm clamp, which was originally in use and stayed just since no one moved it, was the culprit. The ground was moved to the Star ground point on the machine, where it should have been placed anyway. The ground to the hyperthem is now within reference of the table.
When @yashsedai and I ran a test cut after we diagnosed the ground, I noticed that the torch head wasn’t doing the fishing bob that I’d seen it do as of late indicating the THC operation was getting better readings.
Cheers,
-Jim
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Jim,
That’s actually more concerning. If that was with the wire hooked to the table before hand, that means the ground rod is not doing it’s job like it should. Path of least resistance. When doing the ground rod test, the ground needs to be removed from the table and testing the ground rod by itself. Ideally we should be testing directly at the rod but we don’t have that luxury.
The tool provided by Dynatorch actually accounts for the building ground versus the groundrod, so it’s not disconnected for testing.
We made the adjustment of actually affixing the hyperthem ground to the star point rather than relying on the clamping to a slat, and the whole system is now within reference to the rod.
At least that’s my understanding. If you’re available later today let’s take a look at it.
-Jim