Hi.

I have a similar Warco mill in the small workshop. It’s ‘ok’ but one does have to understand it’s limitations, it’s fine for a little ‘indoor’ mill. The mill should only be used with the quill locked, unless either drilling or down feeding with a slot drill etc. The worm on the handwheel shaft can be adjusted in and out of mesh and can be adjusted tighter to reduce backlash, but backlash is always going to be there. If the spindle ‘drops’ when unlocked, it may be that the quill return spring is not properly tensioned, but it should never be too heavy in operation.

In general, when down feeding with this little mill I always have the spindle clamp not fully slack so that it provides a little resistance to keep the quill ‘in check’, and when milling it is locked always. It is only ever fully loose for rapid positioning and or drilling.

At the end of the day, if used with care, these little machines can produce fairly decent work.

Hole that helps…..

It sounds like you have fed it down to depth against the spring using the fine feed then locked it. During use the vibration has moved the quill feed handle over the range of the backlash. However I would expect the quill spring to be strong enough to pull it up when unlocked so that dropping when unlocked would be impossible. Do you use a very heavy flycutter block or something?

It’s because the spring is essentially a ‘handle return spring’ acting on the pinion and, because of the necessity for having clearance between that and the quill rack, there will always be potential for a bit of backlash between the two.

– the pinion has the spring-load but not the lock, and the quill has the lock but not (always) the spring load – it’s okay but not brilliant.

I always run the cutter clear of the work before releasing the lock, and fitting some kind of read-out to the quill helps immensely because you can then see where the quill actually is, all the time..

Diogenese has sussed it. There have been two solutions written up in ME over the years – one was to replace the spring with a Tensator spring acting directly on the quill and the other was an eccentric bush for the pinion to take up the clearance with the rack.