Definately a scrapyard challenge

[JAZZCNC]

In terms of speed and acceleration 1610 screws outperform 1605 by a large margin. Even hypothetically running a 1605 at 2:1 is still inferior in performance to a 1610 at 1:1 due to higher K.E.

Ok can't resist got to jump in.!!!:twisted: . . . Don't need to worry about 5mm pitch being inferior because of K:E bull shit etc because it don't mean jack shit for a DIY machine, it will still perform more than good enough.! . . ( If built good enough.!!)

Yes jonathan's correct when he points out that the calculated physics way of looking at it that 10mm pitch wins for a router!. . . BUT. . . I can tell you because my machine use's 5mm pitch geared 2:1 it's absolutly no problem and in no way limits the performance. Actually IMO it's a bennifit because it's just a simple belt/pulley change to gain resolution.

That said I agree that 10mm pitch (except Z axis then 5mm) would be better choice for a router which mainly cuts wood or plastics. Anything harder IE Ali etc and then extra speed 10mm pitch gains is wasted as the feed rates dictate. 99.9% of the time you'll be lucky to cut any where near quarter the speed 10mm pitch allows.!

An often over looked and misunderstood area which Jonathan touched upon earlier is acceleration.!! . . . IMO and experience for most jobs (Esp 3D) that don't need high feeds (2mtr/min or less) then your much better off tuning your motors to give higher accel than velocity. . . Often less is more.. . Like in the Aztec case where there are lots of short moves it can and does often make job's faster. 3D and v-carving really see the most increase's from high accelleration.

I use Mach3 and it's such a simple job to create profiles that you can easily tailor for specific job types or conditions. IE I have 3D profile tuned for Accelleration. 5mm pitch profile (pulley/belt change)for when resolution needed. I also have profiles for Inch units for each so when I get given code that use's imperial measurements I don't have to fanny about changing settings or code.
Doing it this way makes it very simple and quick to change from one to the other.

So Like 2eOpoz I 100% agree 5mm pitch will be fine in your case.!. . . . BUT . . . 100% Agree with jonathan 10mm pitch rules for a wood/plastic router.

Anyway the screw pitch or speed will be the least of your troubles if you don't beef that gantry up.!!