Snipeye

I'm working on a solar panel factory - my first factory. I've got a bunch of geothermal generators all set up and powered by lava cells, it's all running on EMC generated by a "macerate then re-condense blaze rods" setup. Anyway, my next step is trying to get automatic crafting tables building machines - I can't even make the copper cables to go smoothly. I'm using MkII's, since my whole system runs of pneumatic tubes (to avoid overflow) and the problem I'm running into is that even though I've hypothetically worked out the timing exactly correctly, some items are coming into the crafting table faster than others - so I end up with say, all rubber and no copper in the crafting table chest, and it can't make cables. I was wondering what the best way to avoid this is?