What cnc plasma table is best choice?

[jimcolt]

Things to consider when deciding what cnc / plasma table to purchase should involve a lot of things, I call them "Purchase Criteria". Being in the plasma cutting business for almost 41 years (all with Hypertherm) and having built 6 or 7 cnc tables over those years, and having a CNC Plasma in my home hobby shop are my qualifications for writing this post. Keep in mind that I am talking about entry level and light industrial cnc plasma tables here, generally in the $4000 to $40,000 price range. There is also another whole world of high end industrial plasma / cnc machines that have been around for over 40 years, priced in the $80k to $ 1 million dollar range....which I am not referring to here.

On a number of online forums and Facebook pages that involve metal fabricating I am asked which cnc table is the "best" every day on multiple occasions. First I have to ask these questions; 1. What materials and thickness do you need to cut? 2. What material and thickness will you spend most of your time cutting? 3. Are you an occasional hobby shop cutter for your own use, or are you a business with plans for expansion that will rely on this machine for a paycheck? (an idea of usage in hours per week or shifts per week). 4. What are you cutting (art, hot rod parts, prototype parts, production parts?). 5. What kind of tolerances do you need? 6.Budget?

From the answers to these questions you can develop a bit of a plan regarding the machine that will suit your needs. I do find that you will get a lot of answers from users that already have machines that theirs is the best.....this comes from the fact that they have already been through (at least some of) the "learning curve" and may have forgotten some of the start up difficulties encountered with a fairly complex (software, electronics, process settings that are all critical) machine like these. If I see responses that indicate very tight tolerances, difficult parts to cut, comparisons with laser cutting on thin material, and most of all a budget that will only allow extreme low cost machines, then I get back to the potential buyer with some warnings about expectations and purchase dollar levels.

So....this is one of those areas where the old saying "You get what you pay for" is mostly true. If you have a budget of less than $10k and are looking for a machine that will cut production parts with tolerances that match the local shop that has a $400k Mitsubishi laser, well then you will not be happy. With todays CNC Plasma technology almost anyone can come up with a design for a cnc plasma that will cut metal. Almost everyone that I know that has built a machine for their own use has at least considered starting a business that builds and sells cnc plasma machines....and the entry level / light industrial table market has grown from 2 suppliers 20 years ago (Torchmate and PlasmaCam) to over 40 suppliers here in North America (there are over 100 suppliers in China). About 12 of these 40 cnc plasma suppliers have strong business ethics, business plans, and after sale support that will keep their customers running and satisfied for years. (parts inventory, tech support, documentation, owners help sites, etc.). Machines from these 12 or so manufacturers do cost more than machines from the other 28 suppliers.

So.....why can't you get the same long term performance with lower cost machines from small manufacturers? Support after the sale takes time and costs money. If a company only has 20 machines in the field this is do-able and manageable. Every time a machine hiccups, a call or email is sent to the manufacturer, and with maybe 20 machines in the field the manufacturer can spend the time training, troubleshooting, supplying part numbers, etc. Some of the early manufacturers have in excess of 20,000 machines in the field, and being complex, there will always be issues and contact with the machine builder. How do these companies with so many machines keep up with the after sale support? The answer is that they have smart business planning that built this into the structure of their company, the selling price of the machine, etc. The end result is that companies that have been around for a while and continue to keep their customers happy are the ones that have balanced the business. I have seen a number of cnc table manufacturers go "belly up" and fail when after the sale support gets too time (money) consuming. Ask questions about the installed base and how the manufacturer supports in now....and how they will 10 years from now....the answer is important!

Low prices are always enticing. If you are a quick learner, good with software, electronics, mechanics, etc., then you can allow Low Price as being one of the top purchase criteria for a cnc plasma, just don't expect the same levels of cut quality, software, mechanics, and factory support that you will get from the experienced companies with larger installed bases of machines. If you have these skills you may also want to consider building your own cnc / plasma. Again, on the first attempt don't expect the same performance as the "Top 12" machines....but everyone has to start somewhere!

Here are some suggestions that I though were very well put by Tom Caudle, founder of http://www.candcnc.com , designer and builder of CNC electronics (and THC) for cnc / plasma machines.

Things that should give you pause:
•any vendor that fails to show you the user interface and what the software is and if you get licensed copies
•At least some idea of the controller. There are really cheap (and poor) controllers out of China that do not perform well
•What is the warranty and what does it cover? Remember a lifetime warranty is only good if they outlive you .
•Is there any way to get support besides calling and leaving a message?
•A leadscrew drive. It presents multiple problems that are not easy to solve. On a stepper motor table , Never take the max speed as the max cutting speed. Its not. Typically its about 1/2 of max speeds.
•Beware where the entire sales pitch is a video of it cutting a flat piece of metal.
•How long have they been building and selling tables? Mortality of CNC plasma table vendors is high.
•There have been a string of vendors that are probably great and honest guys but lack business skills. Some were actually crooks that popped up, sold a few tables took a bunch of money then vanished, only to show up somewhere else (case in Point Lightening CNC)


Best regards, Jim Colt Hypertherm