Official Page Launch February 2nd 2018!!!
Plasma tables come in all shapes and sizes and it can be difficult to tell the good from the bad just by a picture. Lets start by breaking tables down into a few simple groups and defining some terms.
Tables Sizes -
I have a lot of people ask what size table should I get? This is difficult question and you need to really think about this one. The cost difference between sizes is relatively small. Most of the cost is in the electronics, controllers, software, computer, and plasma cutter, the components that all the sizes have in common. I try to steer people away from the 2x2 table. Its so small and easily outgrown after a very short period. I hear so many people say I’m only going to cut these small widgets so I don't need a big machine. After a couple weeks of cutting they realize how amazing CNC Plasma cutting is and they want to make a million other things but they have a 2x2 table and are stuck. Unless your on a submarine I would skip this size. When it comes to size really consider what you want to do and what you may do in the future. If you buy one size bigger than you think you will need your probably going to be pretty safe. One quick note on Indexing sheets -
Water table -
Example of an air scribe setup that would be mounted next to the plasma torch on the gantry
Proximity Style Limit or home switch
Limit or home switch that activates with contact from another part of the machine
DIY Laser Cross hair system mounted to the torch
Plasma Rotary Tube indexer, Round tube or pipe rotaries are more common and easier to make. Square, rectangle and angle iron rotary attachments are usually only found on the high end machines or purpose built system.
Down Draft Table -
Open Table -
Build your own -
Steppers or Servos? -
Stepper Motor -
Inside the device, sets of coils produce magnetic fields that interact with the fields of permanent magnets. The coils are switched on and off in a specific sequence to cause the motor shaft to turn through the desired angle. The motor can operate in either direction (clockwise or counterclockwise). When the coils of a stepper motor receive current , the rotor shaft turns to a certain position and then stays there unless or until different coils are energized. Unlike a conventional motor, the stepper motor resists external torque applied to the shaft once the shaft has come to rest with current applied. This resistance is called holding torque.
Servo Motor -
Frame Design -
Linear guides and bearings -
This design of bearing on a rail or bearing on a piece of cold rolled steel is common place in the less expensive tables.
V Groove Rails and bearings are a step up from the bearings on rails and have better precision.
This is a picture of the WestCott Pro Series table system with 35mm Precision Speed guide rails with 6 roller bearings per side.
Electronics Package -
For build your own and some of the kits out there your likely to see GeckoDrive Kits for the steppers. These run your stepper motors and can then be connected back to a computer through a parallel port which is something you do not find on most new computers today so keep that in mind. When it comes to software for these most often you will see them using MACH3 to control the steppers and SheetCAM or another CAM software to control the cut paths. For a full breakdown on software see the SOFTWARE PAGE.
For many of the kits and a lot of the build your own a very popular option is the packages from
Flashcut CNC, they offer Software that integrates your CAD -
tool path software” and the CNC Control software that actually tells the steppers or servos what
to do, where to go and the torch when to fire and for how long.
For my newest machine I went with Design2Cut Software which is a proprietary version of the
Flashcut Software, it has a lot of custom features and intuitive design components that make it better
than the other versions. My machine will also operate using the iCNC controller from Thermal
Dynamics. This controller is a true high end industrial grade control system which is purpose built
for plasma cutting and has many features and options your not going to find in a hobby grade or
light production grade table.
One of the features your going to want to make sure you have is Torch Height Control or THC. In
Simple terns, torch height control is software management of the height of the torch over your
material cutting. Typical torch tip to material or “work” is 0.06 inches or 1.5 mm. This is a
very small gap that needs to be maintained with absolute precision in order to maintain accurate
and quality cutting results. Plasma Cutting is a no contact operation unlike a router or mill. If the
Plasma torch comes in contact with the work surface at any point it can throw off the cut as well
as all the cuts after that point by moving the material or causing the torch to loose its position on
the table. When you consider that you are trying to maintain a 1.5 mm gap at speeds up to 300
Inches per minute or faster across a 4x8 or 5x10 work surface there is no margin of error. That is why
its critical that you have Torch Height Control that is accurate and can keep up with the machine and adjust to the contours of the steel while cutting and maintain the proper cut height. Steel can flex dramatically during cutting due to the heat.
Most machines these days come with some form of THC and there are several companies that make add on THC modules for kit or DIY tables. My first table did not have THC and it was very frustrating when a collision would occur or the material would warp and not get cut cleanly or completely. I would consider THC as a mandatory option on any table.
Table Options & Accessories -
Lasers, Many machines have a laser dot or a laser cross hair that can be used to visually reference where the torch will fire. The laser pointer can aid you in being able to line up a point on a jig or when cutting tube or other products with a defined point that you can reference and start from. Air Scribes, a pneumatically driven scribe with a diamond or carbide tip and are used both for artwork and for marking locations on the surface your cutting for writing text and part numbers.
With Plasma like many other things as quality
increases so does the price, and the same goes for accessories. Determining what you need now as well as in the future is very important.
Thermal Dynamics iCNC
|WHAT IS PLASMA|
|G CODE DEFINED|
|WHAT DO I NEED TO GET STARTED|
|WHAT CAN I DO WITH A CNC PLASMA MACHINE|
|HYPERTHERM PLASMA CUTTERS|
|WATER VS DOWNDRAFT|
|STEPPERS VS SERVOS|
|WESTCOTT PLASMA TABLES|
|PLASMA TABLE SHOPPING GUIDE|
|DESIGN SOFTWARE CAD/ART|
|PRO SERIES TABLE TUTORIALS|
|COREL DRAW TUTORIALS|
|HYPERTHERM POWERMAX TUTORIALS|
|PRICING YOUR WORK|
|MARKETING YOUR PLASMA BUSINESS|
|WHERE TO BUY SUPPLIES & CONSUMABLES|
|NAMING & ORGANIZING FILES|
|TURNING YOUR HOBBY INTO A BUSINESS|