Hi,
this thread is very old, so it is likely that you wont get a reply.
I assume you are asking about the ability to control the spindle with Mach3?
If that is the case can you tell us about your spindle. The title suggests that you are using a Proxxon router. Is this the case?
Again assuming my guess is correct then a Proxxon router is an example of a 'Universal AC motor', and is common in routers, fans, vacuum cleaners and
many other consumer devices. They are constructed very much like a brushed DC motor but are intended to be supplied with AC power. They are
remarkably good and very economical to mass manufacture and hence their popularity.
One of the shortcomings of the Uni-motor is that it is not a well suited to speed control. You can control the speed by using a Triac, not dissimilar to a light dimmer,
but the accuracy of speed control and its speed stability under load is only fair at best. Another issue is that the motor is air-cooled with a fan blade mounted on the shaft.
If you slow the shaft rotation you also reduce the air flow and it will overheat. The air flow is approximately proportional to the square of the shaft speed so reducing the
shaft speed by half reduces the cooling effect by 3/4's, ie a big drop.
A further complication is that the current in the motor is largely determined by the 'back EMF' of the rotor. As the shaft speed reduces the back EMF reduces also
and therefore the motor current will go up, with consequent increased heating.
The two factors combined, ie increase in heating as the speed reduces and a marked decrease in cooling as the speed decreases suggests that a uni-motor run at less
than rated speed may not survive long.
Craig