Random insights to the world of CNC Cutting Machines.
7/21/13 Versatility is Key!
When choosing a CNC table for your shop or home, it is important to keep versatility in mind. Can the table cut steel, aluminum, wood, plastics, pipe, tube, engraving, etc? Customers tend to think when they are looking at a CNC table that their needs are specific and only need to cut one particular type of material. We have found that most of these customers come back to BurnTables and purchase the additional attachments necessary to cut other types of materials because they have found they are not limited to one type of medium like they first thought.
With the ability to change from several available attachments on the BurnTables CNC Tables, as well as having the software included to perform cutting operations in several different materials from steel to plastics, the BurnTables system is the key to being versatile.
For example, If a customer wants to create a new dining room table, but he wants to be different and unique in its design by incorporating steel, tube, aluminum, and wood. One might think you would need at least 3 different machines to get the job done, not with the BurnTables system.
First the customer would draw his designs in the included CAD software to scale. This is done easily with the fully functioning CAD system that is provided with the BurnTables computer.
Second, in the CAM software, he takes his drawings and applies cutting process to each drawing of his design. In the CAM software the customer tells the machine the thickness of materials he is cutting and with the saved tools, the machine knows what federates and tool specifications to apply to each drawing. This allows the customer to be able to create 3D parts from 2D drawings using the router in woods and plastics.
Lastly, the customer will load his materials on to the table, telling the table where is reference point is. First he would start by putting up his steel and aluminum pieces, as the plasma can cut any material that conducts electricity. After cutting his flat steel and aluminum pieces, he would then load his tube into the tube cutting attachment to cut his bevels and design elements like text into the tube with the plasma cutter. After the tube cuts are completed then he would install is router attachment via 4 bolts to perform his cuts into his wood table top.
In summary, with the right CNC table and right attachments, a customer can perform several different tasks in several different types of materials with one table. With the CNC BurnTables system, you can achieve almost anything.
3/28/13 Its all about the Fixture!
With a CNC WaterJet Table system, Fixturing the work material is high on the list to achieve accurate cuts, and seems to be the most over looked items also. Typical WaterJet systems operate at 60,000 PSI of pressure which equates to a handful of down force, but the problem lies with when the jet enters the tank and reflects off the bottom of the tank and then forces the material in the up direction. This cause movement in all 3 axes directions and vibration in the material, especially thinner gauge material. The idea of good fixturing is to stabilize the material as much as possible which is normally done by clamping the material in to a “square” in the corner of the table to limit it x and y motion of the material. On thinner material, a sacrificial heaver material can be placed on top to reduce vibration in the z direction.
Most WaterJet tables do not come with factory supplied fixturing devices because each customer requirements and types of material being cut differ vastly. because of this, fixtures fall to the operator of the table to design and fabricated fixturing devices that securely hold the work piece with out getting in the way of machine movement.
When making a decision on purchasing a water jet table system, keep in mind the design of the table/tank and motion system. A WaterJet system that has the table/tank separate from the liner motion system as in the BurnTables WaterJet System, is superior to systems that are designed as one piece. With the force of the jet exerting against the tank, the tank itself will flex and vibrate. This vibration in turn transfers to the motion system, if they are connected, and results in choppy cuts. Choppy cuts an also be attributed to flimsy tank design.
3/19/13 Why ATHC is a must for CNC Plasma Tables.
Automatic Torch Height Control, or ATHC (THC) for short, describes a system that keeps the cutting torch within range of its optimum cutting distance from the plate while its cutting. This system compensates for plate warpage and irregular material heights. On tables with THC, the operator can see increase in consumable life, better cuts, less dross, and higher tolerances.
The standard THC system on our tables was completely developed by BurnTables, it is by far the easiest THC system to use, but has all the features that a $5,000 system would and more!
-Adjustable torch height control, pierce height control, pierce delay, anti dive speed, and torch adjustment speed, all adjustable on the fly while cutting!
-All settings are saved, even in the event of power loss!
-Do you only want the system to reference the pierce height, but not use the THC for that occasional odd cut part, yes it can!
-Consumable wearing out but still cutting, but the height has changed because of the wear on the consumable? Don’t change it out, get more life out of your consumables, adjust the torch height by the turn of the knob, on the fly while your cutting!
-Are you getting slag build up on the nozzle? Don’t stop cutting, raise your pierce height with the turn of the knob, save time make money!
-Cutting holes in you part at a slower speed but don’t want the THC to fight you and drive the torch into the material, With BurnTables antidive features, complete adjustable, and you guessed it…. on the fly! Keeps the torch from diving down in corners also, no matter how slow you go!
-Need cut a part out of a already bent part, with the BurnTables z axis ability to travel 6″ and the Automatic Torch Height control, you can cut up to 45 degree bent parts.
-Have a situation that you need to completely turn off the THC, but yet need the functionality of the z axis to raise and lower between cuts, yes it can do that too.
Did we mention that this all Standard on ALL of our CNC Tables!
2/12/13 Oxygen Acetylene CNC Table Cutting.
Some of our customers utilize BurnTables CNC Tables with the available Oxygen Fuel Torch Attachment to cut thicker steel. this attachment can be mounted alongside the plasma torch and lowered down when needed. In comparison to plasma torches, the Oxy Torch has a few more adjustments necessary to achieve great quality cuts. Some being pre-heat time, fuel and oxygen flows, cutting gas flows, time on after cut, heats, tips, etc.
ESAB has a online guide that helps with the adjustments on the torch and regulators, as well as suggested cutting tips and feed rates for table operations.
One of the benefits of the Oxy Fuel Torch Attachment for the BurnTables CNC Tables is the ability to cut thick steel materials with out having to increase the plasma cutting unit amperage, this is a problem for some shops that do not have access to higher electrical supply to support big plasma power units.
A downside to a oxy fuel torch is that the cutting feed rates compared to a comparable plasma cutter for a particular thickness is slower. With increased heat to the part, the time for cool down after cutting is increased as well as clean up time for oxy fuel parts.
1/27/13 Plasma and Thermal Cutting Glossary.
Hypertherm gives some very useful insight to terms in the plasma cutting world:
What does “blow-back” mean? What are “lag lines”? The plasma cutting industry is full of unique words and phrases. Fortunately, our plasma cutting glossary has answers to those questions and more. Read on to learn what they mean. Who knows, you may just shock your friends with your new found knowledge.
AC: An electrical current that reverses its direction at regular intervals, such as 60 cycles alternating current (AC), or 60 hertz.
Angularity: The measurement of the plasma cut angle.
Auto-voltage™ circuit: Input sensing that allows the system to run on a variety of voltages with no rewiring.
Blow-back: Patented technology provides a pilot arc
Boost Conditioner™ circuit: Hypertherm technology that compensates for input voltage variations.
CNC: Computer Numeric Control
Coaxial-assist ™ jet: Patented jet design boosts cutting speed as much as 20% over conventional designs.
Lag lines: Grooves in the cut surface that are the result of the plasma arc.
Dross: The molten waste material created by thermal cutting processes that often solidifies on the top or bottom of the plate. Also called slag, dross is produced in different amounts and can be easier or harder to remove depending on the cutting process that created it.
Dual-threshold™ pilot circuit: Hypertherm technology that significantly reduces nozzle wear by increasing the pilot current precisely when needed.
ETR™ (Easy Torch Removal): A unique connector design that provides easy switching between hand and machine torches.
Heat-affected zone: The part of the metal that has undergone structural changes due to intense heat. Heat-affected zone (HAZ) cannot be seen. Although one of the side effects of HAZ can be a heat tint that is visible, the size of the heat tint is also affected by the surface condition of the plate. Therefore, the size of the heat tint and the heat-affected zone may not be the same.
HyLife® Electrodes: that last longer than ordinary designs by using the same patented technologies developed for advanced Hypertherm mechanized systems.
Kerf: The width of a cut made by the plasma arc.
Plasma: Plasma, sometimes called the fourth state of matter, is a high-temperature, ionized gas.
Plasma cutting: Process in which electrically conductive gas is harnessed and controlled. A torch holds consumable parts, which constrict and control the ionized gas stream or plasma arc for cutting most common metals.
1/3/13 Dry Air is Good Air!
Having dry compressed air for your machine operations, especial for plasma cutters, is essential for proper machine operation and great cuts. There are several intimidate benefits to dry compressed air for plasma cutters especial in consumable life. With just a slight amount of water in the compressed air supply that is introduced into the plasma arc, the water “explodes” and instantaneously erodes the electrode and nozzle. In short time, a $15.00 set of consumables can become trash.
Here at BurnTables, we highly recommend air compressed air dryer for you plasma cutter. In our shop we use the refrigerated air dryer Hankison HIT35 available through retailers like Grainger Industrial Supply. The benefits of refrigerated air driers over desiccant driers is low maintenance cost and longer run times before maintenance intervals with maintenance consisting mostly of cleaning of the cooling coils in the drier. Also with units similar to the Hankison, the air drier comes equipped with automatic drains for the internal water traps. The only downsides are additional energy consumption and higher first cost compared to other driers.
With desiccant air driers, the desiccant medium absorbs water in the compressed air stream and after some time will need to be replaced when its lost its absorbency. The amount of time it takes for the desiccant medium to become saturated is dependent on the humidity in the air of the surrounding environment of the supply air compressor. When the desiccant is saturated there is very little indication other then intimidate loss of consumable life in your plasma cutter which means additional cost to your bottom line. The benefits of the desiccant air filters is low first cost, energy efficiency and small floor print. In drier climates the maintenance cost (over significant time) may be small to not warrant the first cost of a refrigerated air drier, but high maintenance cost in high humidity climates for desiccant dries would out weigh the first cost of a refrigerated air drier.
Compressed air dries are beneficial to other tools, for example the pneumatic air engraver and pneumatic controls on the WaterJet. With reducing water in the compressed air supply, it cuts down on valve corrosion and allows lubricants to have maximum effectiveness in protecting moving pars in pneumatic controls. With either device, BurnTables recommends a compressed air drier for any climate for maximum performance of you cutting table.