Blobs started to appear on surface of the print

I've bought Sunhokey Prusa i3 kit from China, and I am vary happy with it.

It was printing great for over a week, but yesterday these blobs started to appear on the surface of the prints. As you can see from first image, I've printed the same part just few days ago, without any problems.

I am printing with PLA. Hotend temperature is 205C, bed temperature is 55C, 0.4mm nozzle. I use Slic3r for creating gcode. These setting were always like this, I didn't change anything.

What could cause this problem?

I recently had a similar problem with small blobs appearing, although in my case it started when I switched from a Jhead hot end to an E3Dv6. I tried all sorts of things to get rid of the blobs, but they only away when I changed to a different filament. So I suspect that the PLA roll I was using absorbed moisture while the machine was out of action for a few days waiting for the new hot end. I'll try using the old roll on a different printer when I get time, to see if I can provide evidence for this theory.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

As it turned out, problem was with clogged nozzle. I managed to cleaned it a bit, but not completely. What is the best way to clean PLA from nozzle?

You may want to (delicately) remove the nozzle tip and soak it in acetone to remove the plastic, and then poke a needle through it, or anything else to help remove the blockage.

What brand of PLA are you using? I am using inland PLA, and I have printed and installed a filament "filter" which rubs the dust and stuff off of the filament as it is fed into the nozzle, effectively eliminating jams for me. Search for one of these on thingiverse, and see if the jams still happen. It may also be that there are contaminants inside of the filament, in which case you should invest in a different brand.

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Master Tinkerer