[Ted383]

Nothing new here. Just another guy trying to decide on a plasma table. After pouring over webs sites for the last 3 weeks I have learned a lot but it's all still a bit overwhelming.

I am looking for a 4x8 table in the 18-25K range.
I will be cutting light gauge alum and steel with the machine. The info I have gathered on alum cutting has varied wildly from manufacture to manufacturer. Some say use nitrogen. An article in the January issue of "the fabricator" mag says to use an argon/nitrogen mix. Most say to just use shop air tho.

I have ruled out several manufacturers for various reasons. Any that have a bolted alum frame are out. Any that uses a hand held torch is out.

I have decided that stepper motors will be fine for my purposes. Plus servos (in most cases) are out of my price range.

Both machines below use 4 steppers and THC.

I took a good look at http://www.trackercnc.com
4x8 $23,390

PROS:
Welded steel frame
True turn-key set up. Thermal Dynamics 80 amp and PC are included
Nice control center that houses flat screen monitor, PC and plasma
Off cutting area parking spot for gantry
They tell me alum cutting is laser quality on shop air
Machine shipped 2wks max (free)

CON'S:
No down draft
No water bed
Closed source system (proprietary)
Haven't been able to find much info on Tracker


I'm leaning toward http://ez-router.com
4x8 $18,250 (depending on options)
Thermal Dynamics 102

PROS:
Price
Lots of options
Stout frame
Gantry that is over-kill for plasma (pro or con?)
Open source system


CON'S:
3-4 week lead time
Over all machine price is good but options are expensive.
Side skirting $2,145. This is just a sheet metal enclosure.
Water bed $4,240...yikes!
I asked if I could just make my own water bed and he said yes but they will charge me $1,750 extra for the frame to accommodate one.
E-chain $734. For plastic cable covers??


I talked to MultiCam. Sounds like a nice machine but I have not got the price list yet. I think it will be out of my price range.

The guy at Dynatorch told me "you don't want to cut alum on our machine". "The edge quality is poor enough that we send ours out to water jet."
No matter tho. They want 33K for their 4x8.

Haven't talked to Shop Sabre yet. They use lead screws so it will probably be out of my budget.


Any input is appreciated. -ted


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[jimcolt]

Here are a few pics of aluminum cutting...done on a PlasmaCam with a machine torch mount. 4 x4 PlasmaCam (without plasma) is less than $10k, 5 x 10 Samson (no plasma) is less than $16k.

I have owned Plasma Cam machines for over 7 years...great product. I'm just setting up a new one...and will post pics in a few days.

Jim Colt

The pics were too high resolution...I will shreink them and post later.

[Torchhead]

Take a look at the machines at www.PlasmaRouteCNC.com. They are an OEM of our controls but everything is open source (you can get replacement parts from multiple vendors). The drives are off-the-shelf Gecko drives and with our "Smart" ESP controller, the level of drive failures for ANY reason has dropped from about 5% to virtually nothing. The DTHC (Digital Torch Height Control) is one of the most sophisticated around with user settable THC parameters by Material Type! (on screen cut profiles). It has the new "Tip Saver" feature that keeps the torch from diving on slowdowns, when cutting over voids, or when it approaches the start lead-in. If you look deeper into the control electronics you will see that some of the brands mentioned use a "gap chaser" approach. No digital presets; just start cutting and twist the knob to get the right gap. We had that design in 2003 (THC300) and I cut miles of steel with it commercially. It made me yearn for something better.

Shop Saber uses WINCNC and there is no integrated Torch Height Control (tied in to the toolpath) so you would have to use a 3rd party standalone Torch control. They also know little or nothing about plasma cutting.

If you ever want to use the table for any form of rotary cutting/milling you can't get there with a PlasmaCam or several of the other brands . They do not have a fully functional Z axis under control of the toolpath. The cutting of aluminum is more a function of the plasma cutter and a good Torch Height Controller than the brand of table.

You will find this a good time, and a bad time, to buy a table. The market is changing and the economy is driving demand to lower priced solutions. The good news is that you can find better deals and get more for your money....the bad news is that some of the vendors are not going to survive and if you buy into a closed architecture machine, then you could be left twisting in the wind for support and spares. I doubt the government will step up and cover the warranty of your new plasma table :drowning:

I wish I could get Jim Colt of Hypertherm to shill for me. I would be happy to send him a free MP3000-DTHC advanced Interface (www.CandCNC.com/MP3000-DTHC.htm) but no third party equipment or control software will work with his PlasmaCAM table.:violin:


TOM Caudle
www.CandCNC.com
Totally Modular CNC Electronics

[curlyweld]

I bought from ez route a 5 bye 5 set up. I told them I was going to build my own table and they sent me a drawing, I lowered the cross members 5 inches to accept my water pan. When everything showed up all I had to do was drill two holes on each side to bolt down the aluminum channels which already have the racks bolted in place. Have been cutting for over one year and have had no major problems. I am moving to a much bigger shop and am thinking of making it into a 5 bye 10 table. I have had great tech service and would buy from them again. That's my ez route 2 cents. CURLY

[jimcolt]

Tom,

I'd be happy to look at your products...feel free to send me your info. Anything that makes the plasma work to its best capability is what I'm most interested in! Send me your latest interface capability.....and provide me with details (technical) about your THC capability. The torch height control is key to making any plasma system perform in regards to cut quality and consumable life. If you have the capability...I'd be happy to help you promote it!

The only reason I recommend PlasmaCam.....is due to the fact that they have advanced THC capability....and they have very easy to learn drawing/cutting package....very nice for the entry level users. They provide a turn key cutting machine with servo drives, full function THC and proprietary software that can be iused to design parts...or can import .dxf files and post process them very quickly for cutting. The PlasmaCam system is not for someone that expects high production/high duty cycles, and it is designed for plasma cutting...not for routing or other uses.

I'm not sure what the "tip saver" feature does for plasma.....oxy fuel systems have tips, while plasma uses shields, nozzles and electrodes....please explain this to me!

Best regards, Jim

[jimcolt]

Here are some aluminum parts that were cut with Hypertherm Powermax plasma systems on a PlasmaCam cutting machine. The PlasmaCam machine in the pictures is just being assembled...so it did not cut these parts....they were cut over a year ago on my old 98Z (the first PlasmaCam machine design)

Jim

[Ted383]

Jim, I couldn't find much in the way of specs on http://www.plasmacam.com/indexfla.php but I can see from the pics and vids it's a bolt together. I'm looking for something a bit sturdier. Does it use one motor on the "Y" with a jack shaft?


That one chunk of alum in your pic must be 3/4 or so... what amp cutter was used on it?

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[jimcolt]

The 3/4" aluminum was done at 80 Amps with a Powermax1250.

Yes...there is a single drive motor with a shaft running through the gantry...so it is driven on both sides. It is a lightweight bolt together machine....not at all for heavy industrial use...but a very clever design that provides decent accuracy....low cost shipping, and the lowest price for a full featured machine. The motors are servos..not steppers....and the THC has similar features to high end industrial height controls.

Jim

[Ted383]

The 3/4" aluminum was done at 80 Amps with a Powermax1250.Jim

On shop air?



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[jimcolt]

Yes, shop air. You could use nitrogen... the cut face would be similar, however there would be more dross. The oxygen content in air has an effect on the flow of molten metal...minimizing dross even on non ferrous materials. There is, however a small amount of oxidation (likely) present on the edge that could affect welding processes.

Our Industrial systems can use other gases....on thicker aluminum we would use argon/hydrogen as the plasma gas and nitrogen as the shield....the cut would appear very similar to the air cuts in the picture...but would have better purity in terms of chemical/metalurgy.

Jim

Jim

[Torchhead]

I'm not sure what the "tip saver" feature does for plasma.....oxy fuel systems have tips, while plasma uses shields, nozzles and electrodes....please explain this to me!

Best regards, Jim

"Tip" as in the end of the plasma torch, as the "tip of the iceberg". Where all of the consumables live. It's a lot easier to say TIP than "shield/electrode/nozzle saver". It's not what Hypertherm calls it, but everyone seems to know what I am talking about. Not everyone uses the term "Arc XFer" but we manage get our concepts across.

We don't have fancy printed brochures on the DTHC and other products but here is few highlights:

• Totally Isolated Analog (Arc Volts) input
• 1/4 Volt SPAN tolerance (adjustable by profile)
• Settable upper and lower fault points
• Settable Fault actions
• Settable "tip Saver" [anti-dive/head lock]
• High speed closed loop with software
• Integration with toolpath
• Inital height sensing using reliable mechanical touch off
• Auto pierce delay based on Arc OK
• Auto touch off interval (frequency) control
• Auto lead-ins/outs [using SheetCAM CAM]
• Auto kerf offsets [using SheetCAM CAM]
• Programmable THC delay prevents head bob after pierce
• Programmable pierce height and initial cut height
• Advanced noise suppression and isolation from PC (logic) electronics.
• Preset Arc Gap volts by material [Cut profiles]
• Works with Plasma cutters not setup for machine control (i.e. 600 & 900)
• Low Cost
• Over 1000 units in the field (all digital models)

The features comparison chart at www.CandCNC.com/THCCompareChart.htm may help some.

The technical details on the interface (base unit for interface from the control PC and MACH3 to the motors and I/O devices is at:

http://CandCNC.com/MP3000-DTHC.htm
http://CandCNC.com/DTHC_Detail.htm

We have more units running on Hypertherm machines than any other brand but it works with virtually any plasma unit. I own a 1000 G3 myself.

TOM Caudle
www.CandCNC.com

[jimcolt]

Thanks Tom,

Maybe you could work with me offline to help me understand your THC capability...so I could offer advice when people ask. From your online brochure I get little information about how the THC interfaces to the cnc, as well as to a z axis (do you have a z axis lifter available?). Some other questions:

1. Method (s) of initial height sensing....(mechanical limit switch, prox switch, ohmic contact, stall force, current sense...are some accepted methods). and the accuracy and repeatability of these processes.
2. Initial height sensing for thin plate...and issues with deflection of the plate.
3. Do you use encoder feedback..or a tmer to retract to pierce height after sensing the surface of the plate?
4. Can you index to cut heat after piercing, but before AVC is activated?
5. Can the system be integrated as a standalone THC....on a machine with a proprietary control such as a Burny or Hypertherm Automation control...or is it only for PC controlled machines?
6. Is there a manual control pendant (I saw one in your brochure..but it wasn't clear to me what it's full function was) that will allow full functionality of the THC without a PC interface?
7. Is there a means to interface to a collision sensor such as the pneumatic and magnetic ones that are widely used on industrial plasma systems?

If you want to work with me privately...please respond to [email protected]

Thanks...Jim

[plain ol Bill]

I know and understand you guys might like to work offline in your evaluations but how about keep all us guys informed too of your progress and thoughts.

[Torchhead]

Thanks Tom,

Maybe you could work with me offline to help me understand your THC capability...so I could offer advice when people ask. From your online brochure I get little information about how the THC interfaces to the cnc, as well as to a z axis (do you have a z axis lifter available?). Some other questions:

The THC interfaces to the Control Software (MACH3). MACH 3 runs on a Windows PC and turns it into a dedicated motion controller. It has the THC logic built in. MACH controls all axis (XYZA,etc). There is no separate "lifter". The Z is a full working axis and will perform any 3 axis operation. THC is just one of those operations. That is why you can switch from plasma to oxy-fuel or rotary cutting by just swapping the "head" on the Z. In some machines they use multiple Z's and just switch which Z is active in the MACH profile.

The MP3000-DTHC is an advanced interface (sometimes called a "breakout board") that provides motor drive signals for stepper or servo drives, Isolated inputs for table switches and the THC signals and has 6 auxillary outputs for driving other loads (vacuum, misters, lights, dust extractors, etc). In fact in this system the DTHC module just plugs into the base MP3000 . It can be done in field in about 10 minutes.

1. Method (s) of initial height sensing....(mechanical limit switch, prox switch, ohmic contact, stall force, current sense...are some accepted methods). and the accuracy and repeatability of these processes.

Mechanical microswitch mounted on floating torch holder. Reliable (works with dirty, rusty and painted metal) and repeatability is within .005. Since all it sets is pierce gap that error is negligible. Sometimes simpler is better. Since the Z knows its position you can limit total down movement with soft or hard limits and the floating holder acts as a shock absorber. In 5 years of cutting with a Hypertherm 1000 and Machine torch I have never damaged the torch or broken a shield or cap.

2. Initial height sensing for thin plate...and issues with deflection of the plate.

The weigh of the torch itself (gravity) is the down force on the floating holder. Works good down to about 16ga. On a machine torch the weight is such that the addition of a counterbalance spring that can be adjusted to give low or almost zero force needed, will let it work on metal down to 26 ga or thinner. I have several customers cutting R panel (24ga) with no problems

3. Do you use encoder feedback..or a tmer to retract to pierce height after sensing the surface of the plate?

Don't have to. The control software "knows" where the Z is after a touch off. The touch off sequence is controlled in g-code (via a POST in SheetCAM) that can be set to touch-off (reference Z) every pierce, or at preset distance intervals, so lots of close pierces work off the same reference. MACH is in control of the Z and knows how far it has moved things at all times (even during THC movement). One reason for doing a touch-off (reference) is if the top of the material (work zero) has changed. One of the advantages of having the Z and THC as part of the toolpath is it's treated like any other axis and it's position is constantly monitored. Even after a thousand quick short moves while cutting under the THC it keeps track of the real position of the Z.

4. Can you index to cut heat after piercing, but before AVC is activated?

Yes. It's part of the standard moves. It's handled in software. SheetCAM has several torch parameters you define in the tool table. You can have as many plasma "tools" as you want. Different tip (woops...Nozzle) sizes. You can set the pierce height, Initial cut height, plunge rate (moving from pierce to cut height)pierce delay (not normally used with Arc OK (Xfer)). All that comes across in the g-code and MACH uses it to perform a pierce cycle at the proper height, delay and cut height. Only after movement is released by the ARC Xfer signal does the torch plunge to the initial cut height. The DTHC can be programmed to delay height adjusting (AVC Delay) to prevent the voltage spike from the pierce causing a false fault or head lock. Typical time is 1/2 to 1 sec (adjustable). The DTHC then measures and tells MACH to raise or lower the Z but MACH controls how fast and keeps track of the total moves. It's basically a closed loop. At the end of the cut there is a programmed delay (once again a parameter in SheetCAM and the G-code) that lets the arc die out before lifting the head.

5. Can the system be integrated as a standalone THC....on a machine with a proprietary control such as a Burny or Hypertherm Automation control...or is it only for PC controlled machines?

Since it is integrated with MACH it is not a stand-alone system. The SheetCam->MACH->MP3000-DTHC->Motor drives should be viewed as a complete system. All it needs is a DXF file from a CAD or Drawing program and it provides 3 full axis of motion with the Z being one of them.

6. Is there a manual control pendant (I saw one in your brochure..but it wasn't clear to me what it's full function was) that will allow full functionality of the THC without a PC interface?

The MPG101B hand controller runs MACH (not just the DTHC). Since MACH is in charge of ALL the motion (including Z under THC) then the Hand controller can be used while cutting. It can used to setup the table (Fast, Slow, single step jog, zero any axis, etc). You can RUN, STOP, PAUSE any loaded g-code program and adjust the Feedrate (feedrate over rides) and adjust the DTHC target voltage in one volt steps WHILE Cutting. Once you load the specific program (g-code) and select the specific Target (preset) gap-volts on screen (or use the new Cut Profiles pop-up) then all other setup and run commands can be done from the Hand Controller with one hand (not two)

7. Is there a means to interface to a collision sensor such as the pneumatic and magnetic ones that are widely used on industrial plasma systems?

There are numerous opto isolated inputs that can be used to stop motion or even run a macro. On our Complete Electronics Packages (plazpaks) with our ESP "smart" motor controller, any emergency input that can provide a normally closed (opens on activation) can be used to instantly shutdown power to the motors. It not as critical on steppers because they stop when you stop sending them steps, but we offer full servo based packages as well.

If you want to work with me privately...please respond to [email protected]

I was going to do that but the lurkers want to see our interchange.

Thanks...Jim[/QUOTE]


MACH3 has a strong following of about 15,000 users. It's flexible and open so we can write programs to run with our hardware to the MACH interface. The DTHC is a prime example and well as our MPG101b what has a high speed interface to internal MACH functions. You can write anything from simple script (VB) macros up to embedded C level plug-ins like we use.

References:

www.SheetCAM.com
www.MachSupport.com
www.FourhillsDesigns.com (my commercial decorative steel cutting site)

Tom Caudle
www.CandCNC.com

[jimcolt]

Thanks Tom,

You have answered a lot of questions I had about your THC offering. It seems to have good features for users of the Mach motion software. I think you should address a lot of these types of issues on your web site....there will be a lot less confusion!

Questions:

1. You talk about the "floating head" torch holder....this is confusing to many of us in the plasma cutting industry because a "floating head" to us is the type of torch height control that is used often on HVAC duct cutting machines (Lockformer, Vicon, MultiCam and quite a few others) where the torch is clamped in a housing that has roller balls on the bottom that ride on the thin gauge material being cut. This whole assembly floats on the plate during cutting and retracts via air cylinder for traversing to the next part. This is an adequate method of height control on thin materials where pierce height isn't so critical. I understand your version of a "floating head"...basically a torch holder with a sliding mechanism and a microswitch that activates when the torch touches the plate, which determines the surface of the plate for reference....is this something you can buy....or is it something the individual has to manufacture?

2. A lifter is the common term on plasma cutting systems for the z axis mechanical drive...which includes some sort of slide assembly and a motor...usually with between 3 and 12 inches of z axis motion depending on the need. Some use induction motors or DC motors with simple up/down relay closures to make them control torch to work distance (old school, but is adequate for some applications) but most plasma torch height systems use either steppers or servo motors for better control of height. What types of motors does your heigh control interface to...and do you offer a "lifter" that is ready to bolt on to a 2 axis machine?

3. Do you have plans to make your height control work on plasma cutting machines without Mach 3......say a Burny controller with Sigma Nest software? Or an older PlasmaCam 98Z? (there are many users that love the way their machine works...just need a better torch height control system. You can install a standalone THC such as Hypertherm's Sensor PHC...including a new Z axis torch lifter...without upgrading software)

Best regards, Jim

[Ted383]

Take a look at the machines at www.PlasmaRouteCNC.com.

I spoke to a girl there. She will be quoting a turn key ZR 4x8 with Thermo Dyn 100 amp and water table. I like that they use linear guides on X,Y and Z. And a lead screw on the Z.

After hrs tech support is by appointment? And no support on Sat. When asked "how does it do on alum?" she replied "ok to terrible depending on...".


.

[jimcolt]

I just finished installing my new PlasmaCam DHC2 with a Hypertherm Powermax45. Here are pictures of the first cuts done with the machine today. Some 1/8" treadplate aluminum, some 1/4" steel with holes down to 3/16", some rusty 20 gauge steel, some 1/2" steel. The height control and cut quality worked flawllessly. The Anytime Fitness sign was drawn originally to be cut 4 feet wide...this one is only 12" and came out great!

Jim Colt

Pics:

[Ted383]

Jim, Thanks for posting the pics.


Jim/Tom,
I believe that a good THC is very important. I would like to find out as much as I can about a given manufacturer's THC before buying. What I need to know is what exactly do I ask the sales person?

Keep in mind that I am only shopping machines that use open architecture. Most are running Mach3 and SheetCAM.


.

[jimcolt]

I guess someone needs to define "open architecture" to me. Many machines that run Mach3 cannot switch to other software...as the Mach 3 runs the drives as well as the THC system.

There is some misunderstanding among many when this term is used!

Jim Colt

[Ted383]

I guess I'll also request and explanation of the term because from what I have read around the message board it sounded like any machine running M3 was "open".

But it's not only the ability to change the controller program that I'm after. I would like to be able to replace drive components with off the shelf pcs available anywhere.

Seems the more I learn the less I know.

.