Odd bubbly type of first layer in only a few spots

I've got an odd bubbling issue on my first layer I'm trying to rectify. It is only the first layer that does this.. I am running a maker select w/ 1.75 PLA. I have re-leveled and also replaced the tape. ation in certain areas (I replaced tape and it got beter but still there (See pics below). I think the fact that Lowered my bed temp to 30C may be part of it. I did this to combat elephant foot and it has helped significantly so i'd like to work around it (I did also aising z axis offset did not help enough before it was too high to adhere). However as you can see this first layer issue isn'tconsistent by any means so I don't think Z height is the issue. I'm running a .40mm nozzle w/ 90% extrusion multiplier, 60mm print/ 80mm feed first layer (Throttled 50% for first layer so I assume that reduces both travel and print speed to 30 print/40 feed?) Subsequent layers are all consistent. I don't think I'm over extruding but perhaps your keen eyes see or know something I don't.

Also I don't seem to see any significant extrude temp changes either. Maybe 1/2 a degree.


Thanks much

Dave

Probably the nozzle is too close to the bed.
Increase the gap by 5 100ths of a mm at a time, till the bubbling goes away.

The natural inclination is to go the other way and assume the nozzle is too far from the bed. But weirdly it's the other way round.

I have played w/ z axis offsets quite a bit. I started at +.01 then +.02 if i get over .15 I start experiencing printing/adhesions issues on bottom layer but no change to this bubbling. it seems the 2nd and 3rd layer of my bottom layers flatten it out fine but I'm just worried of other underlying problems this may be hiding. This was the bottom after the print. Disregard the vertical lines as that's the ever so slight gap in my tape. Another thing I'm noticing which doesn't actually show up in prints and I'd never know it was there unless I was watching but I've got these weird triangular cyclic ghosting images in my bottom layers.

Dave

what printer do you have ?
Looks like the build plate or the axies (axis's ?) are not 100% level.

Also have you tried using pva (cheap gluestick) instead of blue tape ?

I had this real bad on a large print (100x100mm) using S3D. First layer height was 150%, First Layer width was 125%. It was not present using Cura ( Initial Layer Line Width at 100%. What I do now in Cura and I am very happy with, is use Initial Layer Print Speed at 20% and Initial Layer With at 125%.
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Sorry guys, not getting notified for some reason.
Printer "I am running a maker select w/ 1.75 PLA."

I was pretty confident I had it level but I did disassbmle the entire printer the other day and noticed the plate that holds the heated bed was slightly bent although since the heated bed was level I don't think that couldn't' be leveled out w/ the height adjusters. I also tried a new buildtak sheet w/o luck. Did get some boro glass to experiment with also. I took a dial indicator to the bed and it was pretty dang close to level. I do notice this occurs more w/ faster first layer print speed. If I slow it way down the first level is pretty much perfect. I find it hard to believe I have to run at 30mm/s for a first layer (60mm/s w/ first layer adjustment of 50%) to get it to lay flat. I had messed w/ first layer height but not width. Maybe i'll try that as well. I also used to use cura and I don't recall seeing it either. I now use simplify3D myself and love it overall.

What are you doing for initial layer height now? Also what are your layer heights when you printed that?

Dave