Blobs at start of layer using 1.2.7 dont exist on 0.9.9

Hey guys I'm fairly new to 3D printing but I have run into an issue and after a whole bunch of searching I have yet to find a working fix(with the exception of running an old version of Slic3r or a different software all together).

Problem: When printing a part that I sliced with Slic3r 1.2.9 or 1.2.7 I get blobs on the exterior perimeter of pretty well all prints except for single layer prints. If I take the same Slic3r settings, drawing, and keep every setting on the printer itself exactly the same and slice it with 0.9.9 the print comes out way closer to flawless. Picture attached. Close box in the pic is sliced with 1.2.7 and far box is sliced with 0.9.9. Can anyone tell me if there is any config changes I can make to correct this problem? When I use 1.2.9 I also get some over extrusion on the top layer and the exterior surfaces get rough as the nozzle runs over the bumps but those go away with 1.2.7 leaving only the blobs where the printer starts each layer.

The only difference is the version of Slic3r. Settings on the printer are the same, filament is the same, ambient house temp is the same, Prints were done with only about 10 minutes between them.

I'm hoping to find a solution because I use OctoPrint running on a Pi for printing and the feature to send the prints directly to OctoPrint is very handy.

In the .zip file I have included the gcode of both 1.2.7 and 0.9.9(much larger file size) prints as well as the config that was used to create the gcode. The stl is the drawing used for the test and obviously the jpg is the picture.

Thanks

Try this:

On the top row of tabs, go to "File">"Preferences" and switch mode to "Expert"
On the second set of tabs go to "Print Settings">"Layers and Perimeters". At the bottom under "Advanced" change the Seam Position to "Aligned"
After changing, don't forget to click the blue floppy disk icon and save the settings before slicing.

Dave

Make sure you're printing the interior perimeters first before the outer perimeters. That way, any blobbing that occurs stays inside the print.

You may also get some improvement if you tweak the retraction settings. If retraction is on, blobbing at the start of a print line occurs after a retraction has been done. Try retracting more in 0.5 mm increments. If you're using a direct extruder, not a Bowden type, you shouldn't need more than 3 mm or so. My machine does very well at 1.5 mm retraction. Try setting retraction acceleration to 1000 or more and speed to 20 mm/sec or so.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]