Is it possible to have too much ISO on the PEI sheet?  

Re: Is it possible to have too much ISO on the PEI sheet?

The alcohol should evaporate, so generally "no". However, I have had times when it seems the PEI gets "seasoned" and starts to adhere better. All I can think of is that something in my cleaning process left a bit of residue that made a difference and a few prints lifted it off.

If it's a persistent problem, as in causing print failures, definitely give the PEI sheet a dunk under the kitchen sink with some basic Dawn dish soap and wash and dry it with clean paper towels. I find that doing this, with no alcohol afterwards, really puts the PEI in its best condition. And of course, avoid touching the PEI surface at all costs!

If you haven't already, I'd strongly suggest you run Jeff Jordan's "Life Adjust" procedure for Live-Z calibration. It is much easier to use and get good 1st layer results with than the on-board Live-Z calibration routine.

Re: Is it possible to have too much ISO on the PEI sheet?

I've been following his Life Adjust for several days trying to get things to work. I had also cleaned the sheet several times with soap and once with Acetone to no luck but today things started working. So maybe it's just the seasoning so to speak that finally happened.

Here's a photo of the next thing I printed and you can see the squares where my previous calibration prints were and that only there do I have good adhesion.

I'm currently making something to cover the whole plate.

Re: Is it possible to have too much ISO on the PEI sheet?

[...] Here's a photo of the next thing I printed and you can see the squares where my previous calibration prints were and that only there do I have good adhesion.
That looks like the 1st layer is very, very low, causing the nozzle to dig in and distort adjacent lines as it prints extrusions. I'd suggest backing your Live-Z way up (make the number less negative), then work downwards. The 1st layer should be smooth. Try knocking -0.05 off your Live-Z level (make it less negative by 0.05) and keep going until those layers go down smoothly. If they simply won't, you've got an adhesion issue.

When you say "soap", do you mean Dawn dish soap? Other soaps may leave a film which could explain everything. Dawn is the best (or your local equivalent) and it needs to be the version without any additives or moisturizers.

Re: Is it possible to have too much ISO on the PEI sheet?

I've been following his Life Adjust for several days trying to get things to work. I had also cleaned the sheet several times with soap and once with Acetone to no luck but today things started working. So maybe it's just the seasoning so to speak that finally happened.

Here's a photo of the next thing I printed and you can see the squares where my previous calibration prints were and that only there do I have good adhesion.

I'm currently making something to cover the whole plate.

What are all the streaks around the imprints of your calibration squares? Looks like that PEI needs a really good clean to me. If the streaks were left by your IPA then check the purity of it, shouldn't streak like that. I use 99.97% IPA bought from a chemical supply shop on Amazon.

Re: Is it possible to have too much ISO on the PEI sheet?

[...] Here's a photo of the next thing I printed and you can see the squares where my previous calibration prints were and that only there do I have good adhesion.
That looks like the 1st layer is very, very low, causing the nozzle to dig in and distort adjacent lines as it prints extrusions. I'd suggest backing your Live-Z way up (make the number less negative), then work downwards. The 1st layer should be smooth. Try knocking -0.05 off your Live-Z level (make it less negative by 0.05) and keep going until those layers go down smoothly. If they simply won't, you've got an adhesion issue.

When you say "soap", do you mean Dawn dish soap? Other soaps may leave a film which could explain everything. Dawn is the best (or your local equivalent) and it needs to be the version without any additives or moisturizers.

Ya, it's not super close is the thing. I thought that for several days -- it's just not sticking. I need to finish some calibration but the 9 square calibration stuff prints really well.

The soap I'm using is some sent free stuff from Costco my wife buys. I'll look at getting dawn. I put down another layer of ISO after that and while the 9 squares printed fine they didn't stick much and then printed them twice more and they were back to printing near perfect.

What are all the streaks around the imprints of your calibration squares? Looks like that PEI needs a really good clean to me. If the streaks were left by your IPA then check the purity of it, shouldn't streak like that. I use 99.97% IPA bought from a chemical supply shop on Amazon.

91% proof from a pharmacy. I use it for my resin printer as well, never had an issue. Sounds like I need to get a different soap to try cleaning with.

Re: Is it possible to have too much ISO on the PEI sheet?

In the Uk we use dish washing detergent such as Fairy liquid

What we call Soap in the uk. Is a fat based product that may leave traces on the build plate.

Regards Joan

Re: Is it possible to have too much ISO on the PEI sheet?

[...] Here's a photo of the next thing I printed and you can see the squares where my previous calibration prints were and that only there do I have good adhesion.
That looks like the 1st layer is very, very low, causing the nozzle to dig in and distort adjacent lines as it prints extrusions. I'd suggest backing your Live-Z way up (make the number less negative), then work downwards. The 1st layer should be smooth. Try knocking -0.05 off your Live-Z level (make it less negative by 0.05) and keep going until those layers go down smoothly. If they simply won't, you've got an adhesion issue.

When you say "soap", do you mean Dawn dish soap? Other soaps may leave a film which could explain everything. Dawn is the best (or your local equivalent) and it needs to be the version without any additives or moisturizers.

Ya, it's not super close is the thing. I thought that for several days -- it's just not sticking. I need to finish some calibration but the 9 square calibration stuff prints really well.

The soap I'm using is some sent free stuff from Costco my wife buys. I'll look at getting dawn. I put down another layer of ISO after that and while the 9 squares printed fine they didn't stick much and then printed them twice more and they were back to printing near perfect.

What are all the streaks around the imprints of your calibration squares? Looks like that PEI needs a really good clean to me. If the streaks were left by your IPA then check the purity of it, shouldn't streak like that. I use 99.97% IPA bought from a chemical supply shop on Amazon.

91% proof from a pharmacy. I use it for my resin printer as well, never had an issue. Sounds like I need to get a different soap to try cleaning with.

I was having problems printing out the MK2 drivers' gcodes for the spitfire, Ends of the wings were curling up making it impossible to build the model. I lightly sanded the PEI sheet with 600 grit sandpaper, washed with fairy liquid and did a final wipe with IPA, got really good adhesion after that

Re: Is it possible to have too much ISO on the PEI sheet?

Got some dish soap that was unscented and not additional additives scrubbed everything down and washed it good and adhesion is really good now. So it does look like what I was using before was leaving something behind and only after lots of prints without putting ISO on (which probably respread the film) did it get cleaned off so the plastic would come into contact with the actual PEI on the sheet.