The best entry-level CNC plasma table for your shop

We’ve seen the market for entry-level CNC plasma tables, sometimes called small plasma tables, grow rather dramatically in the last 15 years, and we’re often asked for tips from people looking to buy an entry-level table for their shop. It seems this growth is driven by the fact that home hobbyists, professional artists, hot rod gearheads, welding job shops, and construction companies now realize they can design and make their own parts.

These entry-level CNC plasma tables – using an off-the-shelf personal computer or laptop combined with a relatively small, low-cost stepper motor or servo drive packages – are available from dozens of manufacturers. Normally, the table arrives disassembled in a crate and takes only a few hours to put together using common hand tools. I equate the difficulty of assembling a CNC plasma table like this to that of assembling a gas grill from a big box store; it’s relatively easy.

As far as tips and pointers when purchasing an entry-level CNC plasma table, we have some advice to offer.

Start with an air plasma system

Air plasma systems, like our Powermax^® systems, are nearly always used for entry-level CNC tables because air plasma systems are the most economical option for these tables. Make sure the plasma you buy has a blowback start (nearly all newer systems do) rather than a high-frequency start.

Plasma cutters that rely on high-frequency AC voltage to start the plasma stream radiate a significant amount of electromagnetic interference that interferes with the PC-based machine control and electronics. Blowback start plasma cutters produce significantly less electromagnetic interference and can be used around CNC microcontrollers and electronics that have not been engineered to withstand high levels of electrical noise.

While a system with a blowback start has a slightly higher upfront and maintenance cost, this fee is significantly less than purchasing a CNC table that is hardened to electromagnetic interference. 

Choose the right power level

When choosing the type of plasma system, first determine the thickness of metal you want to cut and the amount of cutting you need to do. 

Most plasma systems have a 50% duty cycle, so if you plan to cut for a good portion of the day, I recommend buying a system rated above the thickness you plan to cut. That way, the system won’t need to work as hard and you can cut for longer  

Review your torch options

Also, look at the torch options. Though some table manufacturers offer designs that allow you to mount and cut with a hand torch, I do not recommend it. It's much easier to mount and square a machine torch to the plate. Hypertherm plasma cutters come with a quick disconnect torch feature that allows you to quickly switch between a hand and mechanized CNC plasma torch.

• Hypertherm SmartSYNC^® torches with the Hypertherm cartridge automatically set the correct amperage and operating mode, eliminating setup errors. SmartSYNC mini-machine torches are perfectly suited for entry-level tables.

• Duramax® torches are designed for durability and reliability with SpringStart™ technology. SpringStart technology ensures consistent starting and a more reliable torch. Duramax mini-machine torches are available for mechanized cutting and gouging and are perfectly suited for small tables.
  
  
  
  

Make sure your system has torch height control

Some of these tables don't come with a torch height control which makes the table cost less. However, good height control is non-negotiable since it is critical to edge angularity (good cut quality) and longer consumable life.

The torch height control gently touches the surface of the material and retracts to the proper pierce height. After starting a pierce, the torch height control will tell the torch to wait a second or two to allow for a full pierce, then have it move down to cut height. This is critical to good cut quality. If the torch is too low, you risk a collision with the plate. If the torch is too high, you’ll get a kerf that’s too wide, increased edge angularity, dross, and warpage. Once the X and Y motion gets up to speed (after the height control delay timer times out), the arc voltage feedback control takes over to maintain the proper torch-to-work distance.

Choose your CAD/CAM software

Hypertherm offers ProNest^® LT CAD/CAM part nesting software subscriptions for entry-level table users, but some tables do come with CAD drawing software as well as post processor or CAM software that takes the drawing file from CAD and turns it into machine code.

Look carefully at the software packages offered by each table manufacturer before purchasing one. The learning curve and time it takes to master different software packages varies greatly between software programs.

ProNest LT

ProNest LT is a powerful CAD/CAM part nesting software designed for light industrial, mechanized cutting in production environments. It provides professional-grade cut quality at an affordable price.

ProNest’s intuitive screens and a wide variety of helpful features make it easy to learn and use. You can import CAD files, artwork, and signs or create your own designs using powerful built-in tools. Optimized nesting strategies let you nest jobs more quickly and efficiently.

Hypertherm’s built-in expertise ensures the best possible cutting parameters are applied for each job’s unique needs, resulting in sharper corners, cleaner edges, and improved hole quality. ProNest LT also provides advanced features such as advanced part design and development, CAD/CAM import and conversion, interactive manual nesting, detailed reporting, and simplified costing.

A ProNest LT subscription also includes training, automatic software updates, and unlimited technical support.

Select the table size

The most popular entry-level CNC plasma table size or cutting bed dimensions are 4′ x 4′, 4′ x 8′, and 5′ x 10′. You can buy a 2′ x 2′ CNC plasma table, but I don’t recommend it. It's too limiting, and you can’t buy steel plates narrow enough to fit a 2′ x 2′ table. Make sure to account for both present and future cutting needs when choosing your table size.

Conclusion: You may need help choosing the right CNC table

It’s common to feel confused and overwhelmed when you are trying to choose the best CNC plasma table for your shop. There are a lot of features to consider, and you want to invest in the right technology to support your business. We can help.

If you need help choosing a CNC plasma table, ask us! We don’t sell plasma tables, so our experts are sure to help you find the right one.