I've had a recurring issue over the past several months with the quality of my prints. I've had this printer for about two years, FYI, and this issue only started several months ago. In the pictured first layer of my print, you can see a pattern forming due to some sort of inconsistency. The patterns are actually raised, as if there's some air pocket that formed underneath where two lines met. You can even hear the extruder head hitting against these ridges while it goes line to line. But in other parts of the same layer, the print is perfectly aligned with no bubbles. This is seriously annoying, as I've tried various things to fix it, and have even reached out to Colin from MakerFarm (he said he'd never seen this before). However, it's technically only an aesthetic issue that happens on each solid layer, EXCEPT...

This issue may be the cause of my second, bigger issue: my 3d printed extruder gears keep getting chewed up. I noticed from the beginning of purchasing and setting up the printer that there was a fine white powder developing on the gears of the extruder after prints, but it never became a problem for the whole year and a half of printing that I had done. This powder turned out to be the remnants of the small cog gear that goes on the motor. After replacing the original gear, I had the second gear get chewed up after only one 20-hour print, and just yesterday replaced that gear only to watch it progressively getting chewed up as well. So the problem has significantly worsened.

I'm wondering if there's a relation between both issues. Maybe the extruder head hitting against the developing ridges in the layer is putting extra resistance on the gears causing them to wear out almost immediately?

Any help would be greatly appreciated, as I can't use the printer in this state - it can't make it through the 20-hour print without the gear going. Below is a link of pictures of the first layer, from the top and bottom, so you can see the inconsistencies, as well as the chewed up gears. Thanks everyone!

http://imgur.com/a/1fKuD