E3d blob when start and end

hi everyone

I have a problem after several times trying,It still can't work fine.
So, I come here to ask.these two are different setting but look like same.
there are blob appear when every layer start and end.



I use E3d volcano 0.4 and 3d printer build my own style.

Simplify 3d Slice setting is

left one is



right one is cancel wipe and coasting and retraction distance 6mm and no extra restart distance.

I search lots topic but I still can't work fine.

I use a skirt to clean and prime the head to start the print, this works well for me.

for end of print I added gcode to do these functions and in this order - drop table by 5mm - retract filament - home x/y axis.

EDIT:
I just reread it, its on LAYER start and end not print start and end that your issue is!

I use Cura slicer and there is a retraction on layer change setting in cura that should help there.

idk about slic3r or simplify...

Edited 2 time(s). Last edit at 11/29/2017 11:51AM by JustSumGuy.

With that change in retraction i would expect to see a change. The bumps are also in the same places.
Are you sure the Gcodes are different?
Im not familiar with your software so sorry for this really basic question:- You did save the change and reslice after changing the settings?