ISO community help. Free THC to test on your plasma.

Hello,

we are Midnight Manufacturing,

We are brand new to the digital/online community and CNCZONE.

We have been operating for two years offline manufacturing CNC equipment, servicing machines and plasma cutting locally.

over the course of 2-3 years before we started this business we developed our own CNC designs for many odd applications and quite a few little attachments and accessories.

the Torch Height Controller being one of them, it has been tested in our environment for the entire two years of operation so we thought we should share it being it's really easy to use.

that being said we decided to open the store a little shy of being prepared, and we happened to sell a few.. and they have given us good reviews. but in looking through them I was disappointed to see arguments brewing about the hardware being that of myth and legend and that no such thing could exist.

so to alleviate the stresses involved because it's very understandable to be skeptic of a new product on the market. we have decided we will give a few away(we pay shipping too)

Please put in your request on this thread, factors deciding who we will give them too will be:

-seniority

-post count and relevancy of posts

-general rapport with community members

-and have a plasma with a divided voltage of <10 Volts

-have a method of triggering the THC either ARC OK or using G-code to trigger a relay.

-be willing to install it in a decent manor of time and also willing to post a follow up of your experiences in this thread.

-have the desire to stop setting your THC during normal operations

so please post a basic machine rundown of what you have and why you might enjoy having an auto THC, and we will consider you for the freebie.

Thanks in advance and we hope you can all benefit from this as we have.

and we hope that we can join the community without any hard feelings, we are a family based company trying to sell something we believe is a good product, and we back it with a 2 year warranty.

we look forward to your interest and responses.

MMC.

If you don't mind shipping to Australia, I would be happy to test for you. I've had other US based companies send me plasma parts for testing and development (and they have done quite well in sales afterwards). I have a 4x4' table and a Thermal Dynamics A120 120 amp machine controlled by Linuxcnc. I have it configured with a 30:1 divider but could change that to 50:1 as it will spike over 10v on piercing. My current controller supports normal up/down THC signals but if necessary, I could build a custom config to suit your THC. And yes, happy to add a relay to enable your THC. A sheetcam post processor would be welcomed. Just be warned that it will be a warts and all report good or bad from a very experienced plasma cutter who has also delved into THC Internals. If you are not 100% confident in you product then send it to someone else who is not familiar with THC functions.

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Originally Posted by rodw

If you don't mind shipping to Australia, I would be happy to test for you. I've had other US based companies send me plasma parts for testing and development (and they have done quite well in sales afterwards). I have a 4x4' table and a Thermal Dynamics A120 120 amp machine controlled by Linuxcnc. I have it configured with a 30:1 divider but could change that to 50:1 as it will spike over 10v on piercing. My current controller supports normal up/down THC signals but if necessary, I could build a custom config to suit your THC. And yes, happy to add a relay to enable your THC. A sheetcam post processor would be welcomed. Just be warned that it will be a warts and all report good or bad from a very experienced plasma cutter who has also delved into THC Internals. If you are not 100% confident in you product then send it to someone else who is not familiar with THC functions.

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We will definitely consider you for this test. thank you for your response.

an honest feedback is what we are looking for, and what does your system spike too? I can just change the internal divider to suit your machine easy enough.

up/down signals will work but it can limit the effective speed of the THC, for example the THC can control the physical speed of the stepper based on how much correction is needed. computer based THC may/not do this.

also initial height sensing is required. this is how the THC learns the cut height you want each time you are starting a new material.

Thanks for the response rodw

we will contact once we have a couple of responses and get the boards ready.

Thanks, yes, my table has ohmic sensing and a float switch.
We use a 30:1 divider which is a setting on our plasma cutter (also available on newer Hypertherms) to suit a 0-10 volt sensor. It can see 300 volts max at the torch. But the sensor can handle overvoltage to 500 volts continuously so its not damaging. At high voltage, I have seen it peak on piercing and it would definitely go over 300 volts if crossing a void. Without documentation, I can't say how we could integrate Z axis stepper control, but I'm sure it could be done.

Bbmess,

I commend you on your method of getting the word out there about your board, and investing in giving away free samples for testing. I seriously advise you do take up Rods offer of testing as due to his THC knowledge, if he comes back and says it's good, his reputation on various forums will carry some weight.

As the manufacturer I'm surprised you never chipped in on the other thread in this section to answer some of my questions about your THC. Any particular reason for that.

Regarding Rods comment in his response to you:
If you are not 100% confident in you product then send it to someone else who is not familiar with THC functions.

Lack of answers to technical questions can be interpreted as a worry that the products weaknesses may be revealed. You should look at such questions as an opportunity to improve your product if any such weaknesses are found.
So far we've seen a lot of shouting out how great the product is but no one has answered any questions. Not a great way to gain confidence.

I also advise you to provide your offer on Plasmaspider, where most of the members are dedicated cnc plasma table users and quite a few have a good understanding of good vs average THCs. There's no better place to get good feedback for plasma related stuff. There's always someone asking for THC recommendations.

Quote:

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Originally Posted by Beefy

Bbmess,

I commend you on your method of getting the word out there about your board, and investing in giving away free samples for testing. I seriously advise you do take up Rods offer of testing as due to his THC knowledge, if he comes back and says it's good, his reputation on various forums will carry some weight.

As the manufacturer I'm surprised you never chipped in on the other thread in this section to answer some of my questions about your THC. Any particular reason for that.

Regarding Rods comment in his response to you:
If you are not 100% confident in you product then send it to someone else who is not familiar with THC functions.

Lack of answers to technical questions can be interpreted as a worry that the products weaknesses may be revealed. You should look at such questions as an opportunity to improve your product if any such weaknesses are found.
So far we've seen a lot of shouting out how great the product is but no one has answered any questions. Not a great way to gain confidence.

I also advise you to provide your offer on Plasmaspider, where most of the members are dedicated cnc plasma table users and quite a few have a good understanding of good vs average THCs. There's no better place to get good feedback for plasma related stuff. There's always someone asking for THC recommendations.

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we are actually already running an ad campaign on plasma spider, but thank you for your suggestion.

we are confident in it which is why we have launched it after two years of testing which is why we are now selling it.

I decided that rather than joining in on the argument I would offer a simple solution to resolve any worries, give some away, prove that it does what it says it does.


and the purpose of the system is to eliminate setup and constant adjustments which it does very well. we understand this is out of the normal for THC, but it's part of the growing pains associated with tech development.
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it's difficult to explain how the system works without just handing over the code to the competition.

how it works:

your G-code sets your cut height. this system monitors and records the data from the divider and stores data in EEPROM memory.

your system pierces, it begins to cut at your set cut height, this system stores the voltage data and compares it to old data. and because you set the cut height in Gcode. the system maintains that height that you chose. over time the system will actually improve because it will start to save information about the materials you have already cut. this information being the current and voltage you have your machine set too.

so if you run new code on a different thickness with a different amperage or even different nozzle. this system will be baselining itself each time and comparing to old data. and this way if a probe fails or something like that happens. it will know that isn't normal based on previous readings and it will choose an average of the stored readings and utilize that data instead to save a crash or drag.

Hystereses: eliminated the need to adjust this because the system can detect oscillation of the Z axis, therefor it is set to the tightest possible tolerance

Voltage: as mentioned above the system is doing the voltage guesswork so this dial is not needed

correction speed: this is eliminated also by the anti-oscillation feature. when controlling steppers directly this becomes dynamic and doesn't need user input after initial set up

spike voltage: this is a setting to help when crossing over lead ins and/or going off the plate, to help the system not dive. because of dynamic speed and because of the learned data. it can actively adjust this value to keep the torch from diving on its own at different speeds.

on delay: we do have an on delay adjustment too, this is set to a default value. but in cases where you might not be able to use g-code to enable and disable, you would use the plasma ARC OK, and then this delay would make sure the system is done piercing and is moving before it activates.

some if these settings can still be fine tuned with the on board potentiometers, but in our experiences you wont have to adjust them.

thank you for your inputs and outputs on the situation.

if you have more questions please ask them directly to me and i'll try to help answer them.

we are going to be putting out a full length install and usage video very soon because we know our video is short.

beefy your feedback is appreciated and your questions are valid. we are definitely new to this side of the business universe and its good that people are being held to standards when it comes to this type of equipment.

we will put our money where our mouth is and you will have the opportunity to see the system in action.

PS; we will take your up-vote on rodw seriously. once our next shipment comes in ill be in contact with you rodw and we will get one in your hands.
:)

Sounds like it covers most use cases. In the absence of warpage, the torch voltage is very stable so its easy to sample the torch voltage as the THC is enabled. There is no guesswork required. there is a linear relationship between torch height and torch voltage at > 99% confidence at a constant velocity.

However you also need to take into account acceleration slow downs if the system is heading for a corner when you sample as the voltage is going to be inflated.

Its necessary to delay that sampling until the affect of piercing has abated as that increases the torch voltage above cut voltage by about 30% so there is a risk of things going pear shaped if you sample too early.

Good PID based control of cutting height using voltage as the process control variable should eliminate any need for factors such as hysteresis band and correction speed.

Spike voltage/Antidive/Kerf crossing is the most difficult to get right so its great you've achieved that. It requires extensive time and money for material to get it right. It does not surprise me its taken a couple of years..

The one thing I have not hear you mention is velocity antidive or corner lock. How do you handle that?.

if you datalog the voltage trends you will notice that all of those things have very unique fingerprints in terms of how the voltage reacts to those conditions. so because this system isn't simply comparing voltage, it is actually creating a map similar to a timing map in a car (I come from automotive software engineering) and thats kind of how I applied the logic behind how a car can run in different environments such has hot/cold, low or high octane and so on without the driver having to constantly change dials inside the car. the only difference is in a car it usually leaves the closed loop condition after roughly 2k RPM. this system is always in a closed loop and always adjusting the map. so long story short it can recognize a normal cutting trend vs a decel, a gap in the material, or a corner. so if you decel it can see that trend, and because its monitoring corrections it may adjust in the corners the first couple times on that material.. but once it has learned that it will actually slowly rectify it. kind of like engine knock and instead of retarding timing it knows it should actually ignore this new condition and not lift or lower the Z. so in a sense this THC is an ECU that is just taking care of your torch height haha

and in the couple years we developed a range of products related to CNC, and automotive which we will be releasing soon too.

maybe if you are interested we could send you a few prototypes to test under fire with the THC.

Thanks for the greater detail. I'll leave it to PM me if you decide you would like my help.

no problem! I will be in touch soon

Hi Mmcorp,

sorry for the delayed response. Outside of work hours I've been crawling commando style under our house, smashing holes in our walls, etc in order to sort out some water leak issues.

Thank you for the more detailed input/explanation of how your system accomplishes its features. Your explanations do add a lot more credibility to your claims. Although I'm a little confused by the "time based learning" due to voltage sampling, i.e. it seems the system will average the bad with the good over time, such as voltage sampling on an arty squiggly section of a cut, or sampling on a warped plate, I will say I think your background and your way of thinking is the basis for a very interesting THC design.

One thing I would suggest to gain confidence (perhaps you already have it implemented) is the ability for the user to update the boards firmware, when improvements, etc are developed.

Good luck with everything.

Keith

I have to agree on sending one to Rod, he is very good at this and he is also very good at analyzing and detailed reporting of the results.
You can also send one to me, i would love to give it a run, but beware that i will try to destroy it, first through normal use and later intentionally replicating miss wiring, miss handling, or extreme conditions.
I did test a lot of equipment i was sent from manufacturers, but so far from the THC's only Proma Elektronika THC150 survived everything and works as advertised. NDA on the others ! FYI Proma never even mentioned an NDA.
And yes, usually i get paid to do those tests, but i never ask for it as that prevents me from posting my finding on the net.
If you do not mind, head over to linuxcnc.org forum and do a search, i use the same nic there and on the other forums, cnczone.com and cncecke.de, but have not been there in quite a while, also i do not like plasma spider much despite having some very good members, it is used for advertising by a single company and downloading anything requires payment.
I am sure you will find more than enough reasons to justify sending one.
Personally, i use Mesa THCAD.
Regards,
Tom.

Tommy would also be a great candidate to test your THC. He's been great mentor for me.

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Originally Posted by rodw

Tommy would also be a great candidate to test your THC. He's been great mentor for me.

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Awww you're making me blush ! :)

we are greatly considering your offers, we have just been heavily backlogged with orders this week and we will try to get more boards than we need so we can send some freebies out. we are confident it will pass your tests because the system has been running on our 6 tables without issues for probably a combined total of 7000-10000 hours of cut time and we have a dozen customers running our tables with our THC and they actually don't even know about THC in general because its something they never had to fight with hahahah we just trained them on designing parts in fusion and send them on their way.. if we had promas we would need more skilled operators, and more total operators, our customers would need constant help.. this solution is aimed at guys who would rather walk away from the machine rather than stand there staring at an arc basically.