Holes in my prints!

[aaroncm]

Hey guys,

I've been having an issue with my printer for a while now, basically, from what I can gather, my bridging ability is terrible!

Printing with 20% infill, the bridging over the top of the infill when it reaches the top of a surface, is bad, and by the time it's completed printing the surface over the infill, there's holes. There's also beautiful flat spots, but usually a fair few holes and cave ins.

I've also noticed that when it's printing infill, usually a diamond pattern, there can be a few spots where the 4 support walls intersect where one of said walls won't join. See here: http://cosketch.com/Rooms/ywdfxow

And one more thing I can see, is sometimes the outer visible walls of a final print have distortion.

I've tried a few spools of ABS I have, all 1.75mm. I've been using the latest version of Cura, with a perfectly level bed. I've tried different extrusion multipliers. I'm using a Bulldog Lite and the Steps/mm are (I think) 107. I've tried different temps, bed temps, speeds, etc. I can't figure it out. When I try to do bridges that are around 10mm wide, it's really really bad. Oh, I've also tried slic3r and Pronterface, still no luck.

I've had the printer for a few months now, and I've been working on it ever since making it better and better, I love it but I'm starting to wonder if I've always had this issue, because only now have I started printing things where this issue could be seen. Except for the infill, I don't remember noticing the effect I'm getting now.

Any information you guys can provide regarding this is appreciated, if I've left any missing information out, let me know!

Thanks!

Edit: Just to add, it's a Prusa i3 build, and I'm using a Bowden setup with an E3Dv6.

Another Edit: Here's an image of bad external walls: https://www.dropbox.com/s/su0r8lx2n4...%20pm.jpg?dl=0