Custom Woodworking Business asked several manufacturers and distributors for tips on how custom woodworkers can improve their productivity and abilities on their CNC routers. An abbreviated version of their responses appeared in the March 2007 issue. Below is the full-text version of their complete comments.

Michael DuPont, product manager – CNC machinery, Altendorf America
Think of your CNC machine as a printer. You want to move from your design system as quickly and smoothly as possible to the machine. Your operator at the machine shouldn't have to go through a bunch of gymnastics to get the part loaded and running, either. Allow the machine to take the mundane stuff off your shop people and produce it quickly and accurately. Another point - labeling. Be sure to adopt some means of labeling parts so that there is no confusion over what just came off the machine and where it goes.

Randy Huey, regional sales representative, CMS North America Inc.
A machine PM (preventative maintenance program) allows factory-trained technicians to gain access to the CNC machine for the purpose of checking, verifying and calibrating or correcting the CNC machine to factory specifications. A properly conducted machine PM keeps the machine producing at factory-intended efficiency. A machine that has lower down-time equals higher productivity.

CMS has determined through extensive machine document recording through telephone support and technical interventions that machines that participate in a PM program experience far less overall down-time than machines that only receive regular maintenance or limited maintenance through a customer's in-house maintenance department.

Another advantage to participating in a machine PM is the ability to detect a potential failure of the machine. This offers the machine production to be scheduled at the convenience of the repair, rather than having a failure to surprise the production schedule at the most inopportune time. (This, I believe, is one of Murphy's laws.)

Overall, a properly factory-maintained CNC machine increases productivity and offers operating cost efficiency throughout the production cycle and reduces the maintenance department budget.

Craig Sexton, vice president of sales and marketing, Biesse America
There are too many people still selling and buying machines and software without being educated on the entire implementation process. The most successful installations are with companies that have spent the time to truly educate themselves on all the details required to successfully integrate these machines in their particular environment. Education will give you the means to make an intelligent decision on the technology that's right for you. Without being educated, you can buy the best machine and software in the world and not get the throughput you anticipated if implemented incorrectly.

Jack Lim, vice president of sales, Omnitech Systems
One way to get the most from your CNC routers is to understand your application needs and the full capabilities of your equipment or the equipment that you are considering to purchase. Then choose a CAD/CAM software package that would be able to drive the machine to utilize all its features and functions - if applicable. Any CNC router is only as good as your ability to program it, and a good CAD/CAM software package is the key to driving productivity.

Most small businesses owning their first CNC routers get limited training time on their current application(s) from the OEMs, and usually no further training is obtained after the initial equipment purchase/training. Therefore, most small business owners aren't able to realize that they could pursue and offer other products and services to their existing and new customers. Consult with the OEM; in most cases, they are the best source in solving your application needs - either directly or by providing you with a resource.

Ken Susnjara, chairman, Thermwood Corp.

Once a CNC router is cutting, productivity is determined by the material
and cutting tools. At this point, significant improvement is unlikely since
much effort has been focused on this area already and all systems are very
productive. Real productivity improvement is possible, however, before
cutting starts.

Improved integration between the design software and the CNC control can
yield significant improvements in productivity. For example, design
software that creates a separate file for each sheet in the job and another
separate file for each part that requires a flip operation can generate 75,
100 or more separate files for a large job. The operator must then deal
with searching, sorting and selecting files, which adds considerable time
to the overall processing of the job and reduces the percentage of the time
that the machine is productively cutting.

Other systems, like eCabinet Systems software integrated with a Thermwood
CNC control, send a single file from the design software to the control. The
control then creates the programs needed for the individual sheets and
guides the operator to load appropriate sheets as needed. File handling and
the associated lost time between sheets is eliminated, which means the
machine spends more time cutting and less time waiting for the operator to
locate and load program files.

For flip operations, the CNC control prints a barcoded label for each
part. The operator then scans the barcode and runs the part, again
eliminating lost time in file handling. This approach also results in fewer
errors and thus fewer scrap parts.

Today, in nested-based manufacturing, real productivity improvements are
possible by simplifying the processes before cutting actually begins.

Paul Cullen, vice president and general manager, CNT Motion Systems
Without a doubt, good nesting software allows you to dramatically increase production and minimize raw material waste, while optimizing your machine's performance. The fundamental requirement for getting the most out of your CNC router is flexible, efficient control software.

Michael Cassell, CNC product manager, Holz-Her
Continue to gain knowledge on the software you are using and get to a point where the software is working for you and you are not a slave to it. Investigate various niche software packages to increase the productivity of your machine by allowing you to enhance your current product or move into more lucrative markets/products. Use the software to streamline the programming process. Use macros and/or parametric programming to build a library of attributes to eliminate having to reprogram the same components over and over.

Kevin Walsh, sales manager, Richard T. Byrnes
Use the right tooling and bring in a good manufacturer to help you address not only the style of cutter, but the RPMs, speeds, rotation, etc. Utilize lasers for setup of parts and fixtures. Use proper handling of special board, i.e., facing both sides of it due to wax sealants being used, sealing or edgebanding the edge of the board to reduce the vacuum loss.

Maintain collets and toolholders. This is a huge problem I see in the field. Go by the tooling manufacturer's recommendation of maintenance and replacement. Keep up with the maintenance, lubrication, etc., of the machine, vacuum pump and all accessories. This is worth every penny.

Keep operators trained and crosstrained with the machines and software. Utilize all the knowledge you can for your vendors. Keep up with the newest software that can help with speeding up the office part of the process. Look to tie in design, manufacturing, inventory, shipping, etc.

Bob McFarland, product manager, CNC processing, Stiles Machinery
In terms of nested-based manufacturing, part holddown is one of the
more common challenges customers fight. Programming techniques will
impact how well parts are held in a bleed board or flow-thru vacuum
environment. Where and how you lead the tool in, the ordering of cuts,
tabbing or double pass cutting when appropriate, can all contribute to
more consistent part holddown. Reliable part holddown helps to
eliminate time-consuming and costly reworks which can be caused by part
movement.

In a custom woodworking environment, lot sizes tend to be small. For
non-nested-based applications, part setup and changeover from job to
job will have a greater impact on productivity than any one factor. The
actual time to cut parts is typically fairly quick. Many customers
spend more time setting up and changing over than they do actually
cutting parts. If you can institute a system or combination of methods
for improving setups and changeovers, you will significantly impact the
capacity of your CNC.

For nested-based manufacturing, be proactive in fly cutting your
spoilboard. This will aide part holding and, due to the improved part
holddown, you can often cut faster.

In a nested-based environment where throughput capacity is the goal,
material handling or systems which impact the loading and unloading time
should be strongly considered. Machines are cutting faster today than
ever, so with cutting times becoming shorter, the load and unload time
is becoming a bigger percentage of the overall time to process a sheet.
Material handling might only be 10 to 15 percent of the machine's cost, but can
often impact overall throughput by 30 percent to 40 percent or more.

John Harris, director of sales and marketing, Multicam
Make sure you're using the right tooling, that you're using good-quality tooling, and that you're running at the right feeds and speeds. You'll get much better bit life, and you'll get much better cuts. I think it's generally been more accepted over the last few years that people will want to run a little faster. But in the past, people have wanted to run too slow with these machines and they burn out their bits.

I'm a big believer in keeping your software up-to-date. Software is such an important part of the whole CNC process. There are so many good pieces of CNC software. Try to utilize your software to its maximum. Some people get locked into doing it one way. Go to the seminars that your vendors put on, typically at trade shows, and learn the tips and techniques, because so much can be done with the software.

Mike Reick, product manager — CNC, SCM Group USA Inc.
Nesting has been the buzzword for the last few years, and it allows small manufacturers to either accomplish a level of quality that they can't find the labor for, or it allows them to reduce their labor costs.

This is an exercise we do with our dealers, for justification of the machines. The cost of a normal router is around $100,000 to $115,000. If you take that and you add the shipping and things like that and put it into a lease, we're roughly around $120,000. The rough leasing rate right now is somewhere around $20 or $21 per $1,000 per month. That's $2,400 a month, and divide that by the average number of hours worked per week in a month, which is about 160, equals $15 per hour, per 40-hour work week, is what that machine costs to sit on the shop floor. That's the whole router package, from tooling to putting it on the floor. If you take an average worker, and it varies from state to state, it's at least 30 percent more. A worker may make $10 to $12 an hour and cost at least $15 to $17 an hour. That's more than the price of a nested-based router.

How can a 1- or 2- or 3-man shop do this? If he's willing to grow and hire another employee, that's more than what the machine costs, and at the end of the lease, he's got a machine. At the end of five years, if you're paying a worker, you'll have a worker, who you're going to pay more to over the following years.

As far as a machine's productivity, even if you take one of the slower machines on the market, those machines can do 30 to 50 panels a day. One person machining 30 to 50 panels a day is unheard of. Secondly, while it's nesting, that same worker who's loading the machine can be edgebanding or doing other things while the machine is operating. It allows you to more efficiently utilize that one worker, it increases his accuracy, because there is one setup, and all the parts produced from that one machining cell are all referenced from one another, so cabinets go together much easier. You can produce so much more with a flat-table router more accurately for less money.

There are two groups that have problems [implementing CNC routers]. The first group is people who have done everything manually, including their books and their drawings, for years. It's introducing them to a computer program and/or design. You have CAD/CAM programs out there that can design parts and nest them, and you also have companies out there that allow you to create packages. In those cases, it's getting people to use the computer, get them away from the pencil and drawing board and get them to use and trust in the computer.

The second set of people are fairly literate. The problems they run into are their drawing techniques. An architect may draw in layers. His first version is on the first layer, his second revision is on the second layer, and every time he makes a change, he documents it by having the different layers. When it comes to machining, if they don't erase their drawings, they have everything there, including wording on the drawing. The machines are basically like a large copier. Whatever you give it, it will do, including grabbing some text and printing text as well. You have to train them that at the point of sending these things to the machine, you have to look at exactly what you want the machine to print out. It's the parts, not the text or the dimensioning. It doesn't need a measurement written on there.

As far as a learning curve, what you find out when you install a machine is that at first everyone loves it, everyone is happy, everything is going good, that week the technician is there, setting up the machine. The second week, everything is still in the operator's mind, and everything is still going good. He doesn't venture off much from what he has learned. The third week, all of a sudden he's sewing his oats, and he's getting out there and trying new things. The problem is, he's expanded more on what he's thought about, and he starts running into problems. Of course, he calls the technician, and they converse, and it gets him back on the right track, but he gets a little frustrated.

By the fourth week he has this machine, he's become proud of what he can do and he doesn't want to ask for help. It's human nature. He's trying to do these things, and he's doing some slight things wrong, and it's not doing things exactly the way he wants. He gets frustrated, and he hates the world at this point. But then, all of a sudden, it all starts piecing together once he gets through that, and he comes back to loving it again. That's a normal cycle you see, especially if they're doing more custom things and they're staying away from design software.

I always tell people to expect that. I tell them they might hate me in three weeks, but they'll love me one week after that. It's a normal learning curve.

Illustration by Chris Nititham