Starting Research into THC book

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msimpson99
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Starting Research into THC book

Post by msimpson99 »

I am starting to do research on my next book. This one will be dedicated to THC.

So far these are the systems I will be including in my book.
PriceCNC AVHC10
Polabs PlasmaSensOut
MiniTHC
CAP04 Capacitance THC


All of these provide torch UP/Down signals and have separate interface boards are very easily added to a all my current builds. I have had the CAP04 for a few years not and it works flawlessly as long as you work within its constraints.


The PriceCNC and Polabs THCs are on order, but I have a question on the MiniTHC. I can get it with the Hypertherm interface, or the universal. My initial thought is to go with the universal interface, because I will be using a Hypertherm PM65 with CPC interface and an Everlast 50S with computer interface. I may also test with the new harbor freight unit (No Interface). The hookup on the universal looks much more complicated than that of the simpler Hypertherm interface. In reality I really need both interfaces to write it up, but I am not willing to purchase yet another THC.

Any thoughts?
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Re: Starting Research into THC book

Post by robertspark »

Why do you want to do a write-up?

What do you want it to say that has not already been said or is available?
msimpson99
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Re: Starting Research into THC book

Post by msimpson99 »

Here are just some of the things I will be looking at:


-Issues, with cutting circles and how to handle locking out the THC when cutting tight circles and corners.
-Issues when cutting close to a cutout or edge.
-Repeatability
-Setup and Calibration
-After Sales Service
-Availability
-Cost

On top of that, if the THC makes it into the final book, there will be step by step instructions on how to get it up and running on the CNCCS and its various plasma cutters. I'm pretty sure that has not been written about.

I see a lot of interest in both the PriceCNC and the MiniTHC, Seems like a lot of folks want more information, be it good or bad. My only interest is making my book readers experience at building the machine as straightforward as possible.
beefy
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Re: Starting Research into THC book

Post by beefy »

msimpson99 wrote: Sat Dec 28, 2019 9:36 am Here are just some of the things I will be looking at:

-Issues, with cutting circles and how to handle locking out the THC when cutting tight circles and corners.
First of all, I salute you on your interest in the technical side of things. There's not a lot of this left here.

Just remember, things like the above are not only the THC, they are heavily influenced by the cnc controller capability and the cam programs ability to generate suitable gcode. But not only that, the user may need to tweak the cams post processor to generate suitable gcode.

E.g. Mach 3 has motion pauses when most macros are executed in gcode, whereas UCCNC has many "synchronous" macros available specifically to avoid this problem. The THC is just one tooth on the sprocket that drives the wheel.

I modify the post processor in my cam program to generate whatever code I desire. Then the cnc controller must have the capability to run it to achieve the desired outcome.

For the hole cutting for example you may want to turn of the torch during motion just before the end of the cut. That's a combination of correct gcode, turning off the THC during motion (with no pause in motion), and no pause in motion when the torch is turned off during motion. Heck, that sounded like a mouthful.
2500 x 1500 water table
Powermax 1250 & Duramax torch (because of the new $$$$ync system, will buy Thermal Dynamics next)
LinuxCNC
Sheetcam
Alibre Design 3D solid modelling
Coreldraw 2019
Rodw
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Re: Starting Research into THC book

Post by Rodw »

Well you can't write such a book without considering the Linuxcnc Plasmac configuration which makes the concept of the external UP/DOWN THC's obsolete. The manual is here and its included in versions 2.8 and 2.9 of Linuxcnc.
http://linuxcnc.org/docs/devel/html/pla ... guide.html
The cost of Linuxcnc is free and it will work with any of the THC systems you mention but Plasmac really comes into its own when it is coupled with a Mesa controller board and adding a Mesa Thcad voltage to frequency interface. The frequency is then introduced to Linuxcnc via an encoder input. The encoder count (eg the frequency) which is decoded to a voltage in software 1000 times per second. When the motion controller knows the torch voltage, amazing things can be achieved. The entry level would be a Mesa 7i96 ($119) and a Mesa THCAD-10 ($69)
So lets look at the report card:
1. Hole mode is supported.
2. Repeatability - 100&% repeatable
3. Setup and calibration - not applicable, the defaults seem to work perfectly for all users regardless of machine and material
4. After sales service:
- from Mesa: 10/10 who else creates new firmware for you overnight when you damage the oard as a work around at no cost?
- from Linuxcnc. 24/7 support via the Linuxcnc forum from a committed group of plasma nerds scattered around the world in every timezone.
5. Availability - Always available from Mesa and their distributors worldwide
6. Cost From USD $188 including a free ethernet based motion control board.

With your Everlast, set the board to 16:1 and configure Linuxcnc for a 24:1 divider. There is a post I wrote about this on this forum.
Plasmac has 3 modes to cater for up/down THC's, synthesised ArcOK signal and torch voltage mode that uses PID based control of torch height (via the Mesa ecosystem) Because the THC is embedded in the motion controller, there are features that are not possible with external THC's. This means Plasmac can sample torch voltage, disable the THC when velocity falls coming up to a corner and much much more...

You might also get some useful background in this document in the Linuxcnc docs.
http://linuxcnc.org/docs/devel/html/pla ... rimer.html
msimpson99
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Re: Starting Research into THC book

Post by msimpson99 »

Not going to be looking at linuxcnc in this one. I have dabbled in Linuxcnc, and regardless of what some folks will admit, it does take a different mindset. I have been doing plasma CNC cutting for a while now and have some experience with THC and the different ways of controlling them. Almost all my CNC machines have both Mach3 and UCCNC installed on their respective computers.

I do appreciate the constructive comments, I will be doing a couple books using Linux CNC for my CNC Constructions Set series. So any post will help me with research.
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East German
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Re: Starting Research into THC book

Post by East German »

Hello

You should take a look at the MyPlasm concept from Proma:
https://www.proma-elektronika.com/myplasm-cnc-system/


The CAM is included and everything else you need I am currently testing and have to say I am thrilled.
with probing, THC and control program.

Peter
probing:
https://www.youtube.com/watch?v=L9JaX8A4GDs
cut:
https://www.youtube.com/watch?v=nEb4dVD0BLE
Sorry for my language! The last English class was in 1982.

Homemade CNC Plasma-Watertable
MyPlasmCNC
Hypertherm Powermax 85
Machine Torch
Hypertherm Powermax 1100
Machine Torch
msimpson99
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Re: Starting Research into THC book

Post by msimpson99 »

I have received the three THC systems I will be testing.

One issue I have is with the MiniTHC. I ordered the universal kit which it looks like I did not receive.

I am hoping one of you have used this system can help. Here is what I received:
_MG_7154.jpg
Looks like the Hypertherm interface and a PC LPT interface. No universal divider card. I have contacted the seller, but have not received any kind of response yet.

In addition it looks like the package was dropped shipped to me from someone state side, IE some sort of return that was sent to me. Can anyone shed a light on this. If I cant clear this up, I will be returning the system and dropping it from my tests and book.

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robertspark
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Re: Starting Research into THC book

Post by robertspark »

Yes that is the hypertherm interface kit with it

How would we know if it was shipped from somewhere else? Why do you think it is a return?

Sometimes goods are warehoused locally for shipping...... The Chinese are doing it a lot in Europe
msimpson99
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Re: Starting Research into THC book

Post by msimpson99 »

I ordered the universal kit, not the Hypertherm kit. Big difference in what comes with the main module.

The packaging was from a stateside address, The same ship to address that was originally on the package, but scratched out.

The reason I will look into returning the unit:
1. If I am going to write about something, I need to know specifically what they reader will be getting. Right now I can not say for sure.
2. The reliability of the individual making and selling this device is in question.
3. I am pretty sure this unit was shipped to me by another individual who returned his.
4. It is not what I ordered, I want what I ordered.

While I could use this unit with my Hypertherm build, most folks who have purchased my books are using the Everlast 50s, that is why I want to base one configuration on. My thought was with the universal kit, I could address several plasma cutters.

Here is the thing, I would be willing to use this MiniTHC system if:
1. What I received was indeed the complete Hypertherm MiniTHC kit. IE that kit comes with the main unit, the mini divider, and the LPT board.
2. The seller ships me the universal kit (Hall Effect board, Voltage divider board, LPT board, and the cables needed.

These are possible, but they have yet to respond to any of my inquiries.
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Re: Starting Research into THC book

Post by Rodw »

Having gone from an Everlast 50s to a Thermal Dynamics A120 which is supported by what they sent you, why don't you just make an interconnect cable from the Everlast Weipu socket to the AMP socket used by Hypertherm? aside from connectors, there is no difference between the CNC interfaces on Hypertherm, Thermal Dynamics and the Everlast. All the signals are the same. Thermal Dynamics and Hypertherm use the same connector.
msimpson99
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Re: Starting Research into THC book

Post by msimpson99 »

I could do that, but you are missing the point. I want to try both options on the two different plasma cutters. I also want to do some testing on a plasma cutter that does not have a PC interface.

In any case the MiniTHC folks have contacted me and are sending me the other boards. Probably the best way to go since I will have all the available interface boards.
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Re: Starting Research into THC book

Post by Rodw »

Thats good to hear. This is an interesting plasma cutter for the budget minded as it includes raw arc voltage, ArcOK and torch on contacts.
https://www.amazon.com/HeroCut-Voltage- ... B07YRQ4GLJ

I know somebody has ordered it but I have not heard any feedback on it yet.
msimpson99
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Re: Starting Research into THC book

Post by msimpson99 »

Very interesting plasma cutter, let me know if you get some feedback.

I was also looking at the new HarborFreight Titanium plasma cutter. A little pricey for what you get, unless you can get a good discount. That $400 cutter is also using the same torch I have on my Everlast, so the same consumables. Looks like you can even get shielded consumables for the IPT60 now.
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Re: Starting Research into THC book

Post by Jgorm »

No ess tmc3in1 combo? That's what i settled on.
msimpson99
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Re: Starting Research into THC book

Post by msimpson99 »

An update on my progress.

PlasmaSensOut THC System
I was able to get the PlasmaSensOut system connected, but do to in comparability with my geckodrive G540, I had drop it from the tests. I just could not get a reliable connection between the remote sensor and the main unit. According to the manufacture its because the G540 has a common ground (negative) between the motor power and the rest of the system. Even providing the PSO modules with isolated power it still did not work.

PriceCNC AVHC10 THC System
Got this unit hooked up and working in very little time. It is working perfectly and the voltages pretty much match those in the Hypertherm manual. I need to use it on a few projects to get a real handle on its in and outs. I particularly like the wired signal to turn on and off the anti-dive system. I added some simple rules to sheet cam and can turn on and off the anti-dive with no delays.

MiniTHC THC System
Got this one powered up and the various boards communicating with the main module. I will be connecting it to the CNC and start testing soon.


Here is a link to my writeup intro page.
https://www.kronosrobotics.com/thcintro
msimpson99
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Re: Starting Research into THC book

Post by msimpson99 »

One of the first parts cut with my PriceCNC THC system.
_MG_7359.jpg
_MG_7373.jpg
You can see how I made the part here:
https://youtu.be/OC6ZvEKSFl4

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