PTP vs. CNC: What's the difference?

Technical differences and applications of point-to-point and CNC routers. December 12, 2000

Should a router on a machining center perform the same tasks as a CNC router? Are the differences between the two primarily in the part holding methods? Is there a big difference in software and controller between the two? Can nesting only be accomplished on a CNC router? Are pre cut cabinet parts better processed on a PTP? Are oddly shaped parts better processed on a router? Could a router with a tool changer machine parts like a PTP? Which machine type can do what operations faster?

Forum Responses
In general (and there are exceptions), a CNC Router is a much simpler, more reliable machine than a PTP (I can hear the PTP guys howling already). In a parallel head router configuration you also have the opportunity to work with multiple spindles in the material. The trade off is usually longer changeover time for the router, less machining flexibility (fewer tools available), poor performance on boring operations (slow), and less intuitive programming.

Point-to-point machines are vastly more complicated, more prone to bugs, and do a wonderful job on panel parts such as kitchen cabinets. These machines are usually run without fixtures, have a "Swiss Army" tool selection on board, and set up more quickly than routers. The programming software is usually very easy to learn and use if you are making common panel parts, but can be too "helpful" if you are trying to take more basic control of the machine. Many of the router spindles on the PTPs are just as good as those on the routers, and it is common to see the PTPs doing heavy profiling, and doing it well.

If I were running around the clock making nested upholstery parts from plywood, I would own a parallel spindle router. If I were making European cabinets, I would own a Point-to-Point. For business in the middle, (and most is) you will need to do some analysis and figure out which way you lean.

Routers are routers and PTP are just that--point to point boring centers that can (and many do as standards) have one or more routers attached. So if you are going to strictly do routing, a dedicated CNC router is the best choice. However, if you want to do boring (especially horizontal) and grooving, choose the PTP. Doing your homework and seeing one in production is a must.

Routers and PTP machines have closed performance gaps in the last five years. Our Northwood router has the same drill head that you would find on a PTP and the same positioning speeds. You should look at your primary usage and get a machine geared to that use. If you use a router with a large tool plate for continuous PTP work, it will be harder on it that the lighter PTP heads. If you use a PTP on heavy routing operations, its lighter structure will be stressed excessively.