Can I Use Any Isopropyl Alcohol Wipes with the Smooth PEI Sheet?
 
Notifications
Clear all

Can I Use Any Isopropyl Alcohol Wipes with the Smooth PEI Sheet?  

  RSS
AlexLandherr
(@alexlandherr)
Active Member
Can I Use Any Isopropyl Alcohol Wipes with the Smooth PEI Sheet?

Regarding cleaning of the PEI sheet for PLA printing I was wondering if I can use any isopropyl alcohol wet wipes for cleaning it? Since I can't find them sold separately in the E-shop it seemed like a good question to ask.

Best Answer by bobstro:

The riddle of adhesion

You’ve probably seen some of these guidelines before and may have wondered exactly why these simple-sounding steps work. Here’s an unscientific breakdown.

  1. Isopropyl alcohol and acetone work as solvents breaking apart grease molecules. These solvents do not completely dissolve grease, but do break it down far enough that it can be removed from surfaces easily.

  2. The more concentrated the solvent, the more effective it will be at a given volume. Those little 70% isopropyl wipes do work… on a shiny new PEI sheet. They’re just not effective in dealing with larger amounts of accumulated grease. This is why 91%+ alcohol is recommended.

  3. Acetone is even more effective, breaking up oxidation on the PEI surface, but can make the PEI surface brittle and prone to cracking if over-used.

  4. The amount of grease that any solvent will effectively break down is directly proportional to the volume of solvent to grease. The more you apply, the more grease it can effectively break down. The more concentrated the solvent, the more grease a given quantity can break down.

  5. Alcohol, acetone, and any other solution you apply directly to the bed is just going to move those broken-down grease and grime molecules around. Some will be picked up by wiping with a clean towel, but some will remain on the PEI sheet.

  6. A dunk under the sink with Dawn dish soap is the most effective method of cleaning. Dish soap is a surfactant, not a solvent. It works in a fundamentally different way, bonding both grease and water molecules to wash away contaminants. The reason this is so effective is not because Dawn is “stronger”, but because there’s simply a much greater volume of Dawn and water and the grease is washed away from the PEI sheet.

  7. Windex, a wipe of finger grease, talcum powder or specialized release agents can be used to reduce adhesion when using hot, sticky materials that grip the PEI surface too firmly such as PETG. It is still a good idea to clean the PEI before a print to get an even surface, even if you will be applying a release agent for printing with sticky materials.

  8. If you are printing high-temperature materials (e.g. PETG at 260C on a 90C bed), test to make sure it will release once cool without damaging the PEI surface. You may want to use a glue stick or other release agents for these materials. Test on a sacrificial PEI surface if possible. See over adhesion notes.

A bit of trivia - The reason higher concentrations of alcohol seem to be harder to find is that isopropyl alcohol is most effective against bacteria at roughly a 71% concentration. A bit of distilled water helps slow evaporation, making the alcohol more effective. If you're looking in pharmacies, that's why 91% and higher seem to be hard to find.
Helpful answers are appreciated. I usually respond to Tweets directed at me.OS: Raspberry Pi OS & Windows 10. Programming Languages: Python & Java...
Posted : 04/08/2021 2:53 pm
fuchsr liked
BogdanH
(@bogdanh)
Honorable Member

If wipes contain IPA only (no scents, no "skin care" stuff) then I see no reason why you wouldn't use it for cleaning (any) print sheet. However, I think it's more reasonable if you buy IPA in bottle: is probably cheaper than wipes and will last you longer. There are smaller bottles (about 200-250ml) where you can spray IPA on print sheet and then wipe with paper towel or some micro-fibre cloth.

[Mini+] [MK3S+BEAR]...
Posted : 04/08/2021 6:50 pm
AlexLandherr
(@alexlandherr)
Active Member
Topic starter answered:
RE: Proper Concentration?

But still 90% concentration right? Or can I use something like 99.5-99.7% as where I live there's not much else available?

Helpful answers are appreciated. I usually respond to Tweets directed at me.OS: Raspberry Pi OS & Windows 10. Programming Languages: Python & Java...
Posted : 04/08/2021 7:01 pm
bobstro
(@bobstro)
Illustrious Member
RE: Yes, maybe, but probably not

The riddle of adhesion

You’ve probably seen some of these guidelines before and may have wondered exactly why these simple-sounding steps work. Here’s an unscientific breakdown.

  1. Isopropyl alcohol and acetone work as solvents breaking apart grease molecules. These solvents do not completely dissolve grease, but do break it down far enough that it can be removed from surfaces easily.

  2. The more concentrated the solvent, the more effective it will be at a given volume. Those little 70% isopropyl wipes do work… on a shiny new PEI sheet. They’re just not effective in dealing with larger amounts of accumulated grease. This is why 91%+ alcohol is recommended.

  3. Acetone is even more effective, breaking up oxidation on the PEI surface, but can make the PEI surface brittle and prone to cracking if over-used.

  4. The amount of grease that any solvent will effectively break down is directly proportional to the volume of solvent to grease. The more you apply, the more grease it can effectively break down. The more concentrated the solvent, the more grease a given quantity can break down.

  5. Alcohol, acetone, and any other solution you apply directly to the bed is just going to move those broken-down grease and grime molecules around. Some will be picked up by wiping with a clean towel, but some will remain on the PEI sheet.

  6. A dunk under the sink with Dawn dish soap is the most effective method of cleaning. Dish soap is a surfactant, not a solvent. It works in a fundamentally different way, bonding both grease and water molecules to wash away contaminants. The reason this is so effective is not because Dawn is “stronger”, but because there’s simply a much greater volume of Dawn and water and the grease is washed away from the PEI sheet.

  7. Windex, a wipe of finger grease, talcum powder or specialized release agents can be used to reduce adhesion when using hot, sticky materials that grip the PEI surface too firmly such as PETG. It is still a good idea to clean the PEI before a print to get an even surface, even if you will be applying a release agent for printing with sticky materials.

  8. If you are printing high-temperature materials (e.g. PETG at 260C on a 90C bed), test to make sure it will release once cool without damaging the PEI surface. You may want to use a glue stick or other release agents for these materials. Test on a sacrificial PEI surface if possible. See over adhesion notes.

A bit of trivia - The reason higher concentrations of alcohol seem to be harder to find is that isopropyl alcohol is most effective against bacteria at roughly a 71% concentration. A bit of distilled water helps slow evaporation, making the alcohol more effective. If you're looking in pharmacies, that's why 91% and higher seem to be hard to find.
My notes and disclaimers on 3D printing and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan...
Posted : 04/08/2021 7:14 pm
AlexLandherr
(@alexlandherr)
Active Member
Topic starter answered:
Would Any Dish Soap Do It?

So would any dish soap like this one do it?:

https://en.wikipedia.org/wiki/Fairy_(brand)

Helpful answers are appreciated. I usually respond to Tweets directed at me.OS: Raspberry Pi OS & Windows 10. Programming Languages: Python & Java...
Posted : 18/08/2021 1:41 pm
bobstro
(@bobstro)
Illustrious Member
Fairy is a good UK equivalent to Dawn
Posted by: @alexlandherr

So would any dish soap like this one do it?:

https://en.wikipedia.org/wiki/Fairy_(brand)

Yes, Fairy is a known UK equivalent to Dawn. The only reason Dawn and Fairy are mentioned is that they're known to work. That doesn't mean others can't work equally well. Do watch out for anything with hand softeners or other additives that can mess up your adhesion.

It doesn't help that many products get rebranded every few years.

 

My notes and disclaimers on 3D printing and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan...
Posted : 18/08/2021 2:46 pm
Share: