The Festool HW R1-OFK 500 Z1 Roundover Cutter is a router bit made for delicate edge-rounding work on solid wood and plastic edging. This is a roundover cutter designed for rounding small edges cleanly and consistently. Model Number: 578376. If you are doing finish work where a heavy profile would look out of place, this bit is built for that lighter touch.
What makes this cutter matter is control. With a 27 mm diameter, 1 mm radius, and a single cutting edge, it is aimed at small, precise edge treatment rather than aggressive material removal. That 1 mm roundover is the kind of profile you use when you want the edge to feel finished without obviously changing the shape of the part. It is especially useful on trim details, finished solid wood parts, and plastic edge material where a subtle break on the corner looks better than a sharp arris.
Festool calls out the direct spindle fit as a key part of the design, and that is worth paying attention to. Better run-out accuracy means the cutter tracks more true, which helps produce a neater routing finish. On a small-profile bit like this, accuracy is a big deal because even slight wobble shows up fast in the final edge. The result is a cleaner pass and less sanding or touch-up afterward.
The single-edged Z1 layout is not just a spec line. In real use, it helps limit heat buildup, which can reduce scorch marks when routing across the grain. That is a practical advantage if you are working on visible finish parts where burn marks are a pain to remove without changing the profile. Festool also notes that the radius transitions into a 5° run-out on the router blade to help protect the surface, which is another sign this bit is built for finish quality, not rough shaping.
This cutter is also designed to work where space is limited. The low installation height and flush ball bearing mount make it possible to route in rebates or on a stack of panels without the bit getting awkward or forcing a setup change. That makes it a good fit for edge work on assembled pieces, layered stock, or parts where clearance around the cut is tight.
The compatibility cue is right in the product name: the Festool HW R1-OFK 500 Z1 Roundover Cutter is built for the OFK 500 platform. It is installed with a screw and is supplied without the bearing ball, so that is worth checking before setup if you are replacing an existing cutter. For woodworkers, finish carpenters, cabinet installers, and serious DIY users doing light profiling and edge finishing, this is the kind of specialty router bit that does one job and does it properly.
