First layer problems, again

[stejan 1]

I am really struggling to get a good first layer again. I installed the Micro Swiss all metal hot end recently on my Ender 5 Pro and all has been well for a while. 

Yesterday the dreaded first layer curse struck again whilst printing with my regular PLA (Eryone).

I have been getting really rough first layers and the whole line of filament has been lifting from the bed (not the edges warping, rather the lines of filament 'stretching' and lifting has they are printing).

Things i have done -

1)Re-levelled the bed 

2)Cleaned out the hot end and nozzle

3)Tried various temps from 190 - 220 and bed from 60 - 70.

Attached is a picture of the best layer i could get. Even this has a 'birthmark' (for want of a better word) at the bottom, just left of centre. If you run your finger over it it does feel slightly raised. These normally lift more causing the whole row of lines of filament to curl up from the bed.

Any suggestions always welcome ??

 

 

 

[stejan 1]

UPDATE - I think i have found the solution. I was confused has to why this problem only occurred on the first layer. If it got past the first layer it was fine.

I was 99.9% sure that the bed was level and the offset was correct so i decided to look at what i clean the bed with. I have always used 99.9% isopropyl alcohol to clean the bed has i was told it was the best solution (pardon the pun) and it evaporates away completely.

But i started wondering if it was somehow causing a reaction with the PLA. This morning i cleaned the bed with some warm soapy water whilst the bed was heated and waited for the water to evaporate away. Then i did a first layer test which came out 100% perfect, in fact i haven't seen such a perfect first layer since i bought the printer last year. 

I have done three prints today and the first layer was perfect on each one. 

Hopefully this may help someone else who uses IPA to clean the bed and have found themselves suddenly running into first layer issues.