Better resolution accuracy?

I have a very heavy duty x y table fitted with DC servo motors etc which I
am in the process of converting to a CNC router / miller.

The 1" thick leadscrews are fairly coarse pitch, but all is very well and precision made.
The current encoders (400 steps per rev) give me an effective resolution
of 500 steps per inch of movement which I feel may not be good enough for
routing curves etc ?.

Not wishing to replace the leadscrews or encoders at this stage, I figure
I could increase the resolution by putting a 4-1 reduction system via toothed belts
and pulleys in between the motor shaft and the leadscrew end.

Can anyone in the group offer any info / downsides to doing this ?

Many thanks

Dave Fisher - UK


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