This page provides some answers to the most commonly asked questions about retrofits and DNC. If you don’t see your question here, email us and we will answer personally.
I’ve seen retrofits on other sites for less than $10,000, why are yours more expensive?
Which CNC control is best?
Do I have to change Axis Motors when I retrofit?
Is a retrofit always cost effective?
Will my machine cut faster with a retrofit?
DNC- my shop has lots of electrical noise, would wireless networking work?
How does Machine Monitoring work over a DNC network?
You’re really trying to compare apples and oranges. Most of those other “retrofits” are really just “parts”. A retrofit package should be complete, and able to interface with all of your machine’s functions.
A typical retrofit package involves:
- a CNC control (both hardware & software), capable of controlling your machine axes from both manual and programmed commands.
- input and output (PLC) control hardware & logic, capable of interfacing with your machine’s relays, valves, and switches.
- panel mounting new equipment.
- documentation showing how the machine and retrofit are integrated.
In many cases, designing, building and programming the PLC interface can cost as much as the CNC alone. Of course, machines with minimal I/O; (i.e., motion control only), may be very inexpensive to retrofit. Just remember that the size of the machine has little to do with the cost of the CNC retrofit.
Review our pages on Retrofit Design, and if you have a specific application we would be happy to quote a package for you.
There is no real answer to that, without knowing your retrofit goals, machine’s capabilities, and budget.
CNC controls vary in processor speeds, I/O capability, expandability, standard and optional features, and of course, price.
The goal of a retrofitter is to match your needs with the control at the best possible price. The best CNC control for one application may be the worst for another.
Some of the newer CNC controls will not interface with older analog axis drives, or require expensive adapters; but there are many controls that will work just fine with existing axis motors and drives.
The real question is: Do you want to change motors & drives now? Sooner or later, you will want to replace them if you’re going to retrofit; but some customers prefer to retrofit just the CNC now, and budget for the drives and motors in another year.
Remember, new motors will not necessarily make your machine go faster. It was designed to operate at specified speeds & feeds, and trying to push that may damage the machine over time.
A retrofit will not compensate for a worn or sloppy machine, or drastically reduce cycle times. If these are your goals, either consider a rebuild or replacement.
Retrofiting a manual machine to convert to CNC is seldom economical. The mechanical adaptations are expensive, and the machine was not designed to run at the higher speeds typical of a CNC.
A retrofit on a small machine is seldom cost effective. Small mills and lathes, designed and built with new CNC controls are available, NEW, at a reasonable cost. For more information about them please contact us with your interest.
In general, no. Cutting speeds are determined by material, tooling, and machine rigidity and power. None of those are changed by a CNC retrofit.
However, a retrofit may improve the machine’s productivity in other ways. Features such as High-speed Machining allow a milling machine to negotiate a cutting pattern more efficiently, while Constant Surface Speeds improve the tool life and part finish on lathes.
Further, on-screen program editing, tool path plotting and tool length offsetting all reduce setup times and scrap rates.
You would be surprised at just how well it works!
Wireless networks employ a technique called Spread Spectrum, where packets of the same data are transmitted over several frequencies. Electrical noise may interfere with one frequency, but usually not all. Then, Ethernet’s error detection and correction protocol analyzes the data, and asks for a re-send of any bad packets. Data flow is so fast that all of this is done invisibly to the user.
With conventional Serial Networks the only error checking is “parity-error” checking. When Parity Errors are detected,(which means that noise has blocked a data bit or created one), data flow stops and has to be manually restarted; and if the noise interrupts two bits, then the parity test misses the error, and bad data is sent. Either condition can be critical problems in "drip-feed" applications.
For a demonstration of wireless in your shop, contact us. If you’re in the Mid-Atlantic region we’ll be glad to arrange a visit. If you’re outside the region, we’ll help you find a local rep.