The following appeared in the Trend Inprofile magazine in 1997 and seemed worth reprinting:
Routing encompasses a wide range of skills, not just in handling the router itself, but in using it to its best advantage in conjunction with various, guides, jigs and other ‘routing devices’, as well as the extensive range of router cutters now available. Routing is also about innovation in both the methods and applications to which the router is applied and in the aesthetic and technical design that it is used to create.
Most woodworkers turning to routing have some idea and experience of working with power tools.
Most householders will have occasionally used a jigsaw or electric drill and will know that power tools come in a range of power ratings and capacities - the more power you have, the faster and harder you can go about the job - well that’s the theory anyway!
However, as if you are buying a new car, computer or washing machine, you will still want to know just what to buy to suit you and your pocket. Accordingly, the questions facing the newcomer to routing are most likely to be:
How much power do I need?,
What collet size do I need?,
Do I need variable speed?,
Do I need to buy lots of accessories?,
Do I need to buy lots of cutters?
How much power? - This depends on the type of work that you intend to use the router for.
If you are cutting dolls house mouldings or trimming veneers or laminates, there is little point in buying a heavy duty router. It will be too heavy and clumsy for the purpose. Conversely, if you are making doors and window frames, you would not be able to remove
enough material efficiently without overloading the motor. This would cause the cutting speed to drop, resulting in a poor finish and possible premature burn-out of the motor and bearings.
For many applications the strength of a cutter often depends on the diameter of the cutter shank. The thicker the cutter shank, the more wood you can remove and the deeper you can cut on any one pass, with less risk of the cutter flexing excessively or breaking.
Light duty routers are generally supplied with 6.5mm (1/4”) collets although some models can be fitted with an optional 8mm collet. The introduction of 8mm shanks has allowed many of the larger diameter cutters to be used in light duty routers, although particular care must be taken when using them and any manufacturers recommendations concerning cutting speed and depth of cut must be closely observed.
Most medium and heavy duty routers can be fitted with alternative diameter collets of 6.35mm (1/4”), 9.5mm (3/8”), 12.7mm (1/2”) and 8mm diameter, although most are supplied with only 1/4 inch or both 1/4 and 1/2 inch collets. Alternative size collets are available for most makes and models of router. Do remember that small diameter cutter shanks will flex more, with a greater risk of breakage under the increased load from a heavy duty router. Remember that small diameter cutter shanks will flex more, with a greater risk of breakage under the increased load from a heavy duty router.
(746 watts = 1 HP )
Light Duty Routers
1200 and above
Speed & Variable Speed
Router spindle speeds are generally given as o-load speeds, that is the speed that the motor spindle is rotating at before the cutter enters the wood. This is generally between 8,000 and 30,000 RPM depending on the power of the router. Light duty routers will have a higher no-load speed to help compensate for their lower power. Most routing operations using cutters up to 25mm diameter, should be carried out at the maximum router speed to achieve optimum cutting efficiency.
Operations involving the use of cutters over 50mm diameter should be carried out at speeds of between 12,000 and 16,000 rpm. Variable speed routers with full wave, load compensated electronics, tend to run smoother and possibly quieter than single speed machines, resulting in reduced bearing wear and eliminating the initial jolt on start-up.
They also accommodate the use of large diameter cutters at their recommended safe speed. Aluminium and plastics require routing at lower speeds to reduce overheating or melting, preventing problems such as weld-back, whereby molten waste material re-forms
within the cut, or the fusion of waste particles to the cutter.
The few guides and accessories supplied with the router allow you to carry out various basic cutting operations such as edge trimming, moulding, and template work. However, to increase the versatility of your router it is worth considering adding further accessories toyour routing workshop.
Last edited by istracpsboss; 12-10-2010 at 07:22 AM.