m16 studding work instead of ballscrews ?

[HankMcSpank]

M10 A2 is good; the main issue with the smaller threads is the pitch, M10 is 1.5mm, which makes for slow traverses unless you gear up but then that adds cost/complexity. TR12x3 is £11.40/m (at Marchant Dice) and arguably the best mid-range compromise IMHO between cost and performance

Yeah... M8/M10 can be a little slow...especially with underpowered motors that I previously had! But hey, this is just a hobby (not my day job thank heavens - my family would be perpetually like a nest of newborn starlings) & I justify it by saying "Hey, I can resolve down to 1.5mm/800 steps = 0.0001875mm (as if lol). Also, I'm typically making stuff that's about under 100mm x 50mm (so it's not as if I need to cover a lot of real estate fast!)

That's a good 'bang per buck' suggestion though - 3mm pitch is starting to get a little more like it ...but I guess then there might be a bit of a battle making your own delrin nuts? (then the cost starts taking off)