This first image is with unshielded consumables, all the cuts are the same travel speed and amperage, the shielded cuts are not up to par, Only thing that’s changed is lowered the shielded cut height by .030 to compensate for the tip being inside the shielded cap, the cuts are choppy and looks to be at to fast of a travel speed.
What am I missing, this was with new consumables.
Cut speed is a little to slow, you should have a trailing angle of about 10 to 15 degrees.
Ive nailed down the problem, the torch height control is working intermittently with the shielded consumables , on my line test the torch bobs up and down for no rhyme or reason producing bad results.
tested the thc and says within working limits, but its not working correctly.
The Attached Image is a perfect line cut with THC disabled and the head not bobbing @langmuir-daniel @langmuir-cameron some input would be nice
Are you putting the work clamp right on the metal you are cutting?
Yes directly on the piece, every time i do a line test or a run program with THC enabled the torch (in rhythm) bobs up and down like clock work every half inch or so.
when i run a line test and manually set Th and disable THC it will not bob up and down
How are you setting the cutting voltage?
No need to set cutting voltage when i manually set cut height and run a line test with the correct cutting Amperage?
If i need to set voltage that’s why i line test to get the correct voltage without using smart voltage
What do you mean?
Any time you do a cut with THC on you must either set a target voltage that corresponds to a specific cut height, or you must allow FireControl to do it using smart voltage.
Are you setting the voltage as 0 (smart) or are you entering a voltage that you gathered from doing a line test.
It sounds like you may be manually setting the voltage to a specific target. If so, what are the THC traffic lights indicating when cutting? Is the actual live voltage substantially higher than the nominal voltage which would cause the torch to dive?
I can help you troubleshoot this, a good place to start would be a video of your FireControl screen while the diving behavior is occurring.
Example
I want to cut a piece of 1/2 in a straight 8’’ line
If i allow smart voltage to establish cut height as soon as the cut starts the torch bobs up and down and the quality is pathetic.
if i do the same line cut and manually jog the torch to my desired cut height and THC is OFF the cut is perfect and it wont go up and down when cutting.
Yes I understand the symptoms you have mentioned. In order to solve it I need to know what the THC is doing while it is hunting up and down. Can you take a video of your screen while the bobbing is occurring?
By the way are you running all of the default THC settings?
So with you understanding the problem , please explain possible solutions and or problems without giving vague and meaningless half answers?
There are two main reasons you see hunting behavior. I’ll try to explain both below.
As for the causes, there are a few. The most common is an erratic signal voltage from your plasma cutter. If the voltage is unstable and all over the place you will see this behavior.
As to what’s happening with your specific system, there’s no way for me to know without more information from you as I have requested previously. A video would be immensely helpful.
Im not imputing any values, i will upload a video tomorrow
So whats the simple answer to me being able to produce a perfect cut when performing the same line test with the same travel speed and amperage but without THC smart voltage on?
Based on your previous posts your torch is bobbing up and down when the THC is on which is causing poor cut quality. With good settings and clean input voltage the THC will maintain torch height extremely accurately and definitely not bob up and down.
When it’s bobbing up and down is the torch contacting the plate?
I don’t believe it’s touching the plate, looks to be going up from cut height upward then back down.
As it’s very hard to see and pause it when this is happening
Ok that’s good that it’s not bouncing off the plate.
Try increasing the voltage tolerance from 1.5v to 5v and set the Z speed factor to 3%. Both of these changes can be made by clicking on the THC settings button.
If it still bobs after making these changes, then increase your sampling rate to 100.
Please elaborate on clean input ?
The picture i uploaded couldn’t be any better, no dross almost zero bevel picture perfect cut without THC on.
That is by far the best cut you could ask for in 1/2 HR plate from a plasma Only achieved with THC off?
Why would this only happen with shielded consumables?
Why would I need to set these factors different in smart voltage of it is suppose to correct these values for me ?
By clean input I mean a stable voltage signal from your plasma cutter. One that has low noise thus making for a suitable feedback signal in the control system.
Smart voltage only assigns the nominal voltage as the voltage that was observed immediately following the IHS sequence. It has nothing to do with voltage tolerance, z speed factor, or sampling rate.
When you perform tests cut that produce good cut quality and low dross, are you turning THC off but still allowing the IHS to establish the cut height?
So in foot ball terms explain why turning off IHC during a line cut would produce a perfect cut ?
