Does anyone here ever replaced their PEI sheet on the heatbed?  

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

The thing with freezing the sheet vs heating it is: freezing is a lot safer. I tried to lift a corner at room temperature and it was a huge bother to get just 2 cm diagonally, so I decided to just continue with the freezer + limonene method instead.

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

You said it doesn't stick "anymore" and then mentioned the filament Prusa sent you, is it the same PLA you've used the entire time?
I ask because when I received my MK2 I had other filaments at the ready and did not use the Prusa filament, when I did end up finally using it, I had sticking issues. Then I noticed I received a box that said "PLA" on it but the filament roll said "ABS". If that is the same with you, that could be your issue.

Just a thought.

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

Eric,
Yes, that the PLA I have been using all the time. When I first use the printer with the PLA, it sticks pretty well and the finish print pop right off the bed when the heat bed cool down to room temperature. However, I noticed that after may be 50 prints, the PLA does not stick to the bed as secure as before. So, I am thinking may be the PEI sheet worn out? That's why I am thinking replacing it.

I might switch to PETG entirely, but it left some stain on the PEI sheet which did not happen to PLA and ABS. Is it normal? Or the PEI sheet actually worn out and need to be replaced?

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

If and how are you cleaning your PEI after removing the print?

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

Personally, I have printed hundreds of models and the PEI stillo sticks extremely well. If PETG is sticking well, I would first have a look at your first layer height and clean only with IPA.

Peter

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

I am using 91% IPA after each print of PLA.

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

I am using 91% IPA after each print of PLA.

Just as an experiment, see if you can find 99% or even anything higher than 91%. Those impurities/water matter.

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

I am using 91% IPA after each print of PLA.

I'm pretty sure that there isn't any problems with PEI sheet, I think it will be physical worn down before it starts to loose it adhesive qualities (if it ever can do that). I've also printed a lot more than 50 prints and I have no problems what so ever when it comes to adhesion.

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

Make sure you use non parfumed paper towels, some release oils 😯

Then clean it really well with acetone.

If even that doesn't help, resurface it as stated in the Handbook 🙂

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

I indeed have to confirm what Josef written...
I had some sticking issues as well, and the only way I could stick the print to the bed was by putting the nozzle to close to the bed so the filament got squeezed on it. This worked, but ofcourse didn't end up with a nice and smooth first layer...

Then I started cleaning the bed with an other product, I started using Acetone. And I have to say... WAUW it sticks like hell now! I probably printed over 350-400 hours the past 3 weeks, and cleaned the bed almost after every print, depends on how large/big the print was. No issues anymore since then, so my recommendation is to get a bottle of acetone in you local store for a few dollars/euros and start using that.

Not sure if it is actually needed to replace the sheet, since mine still doesn't show any damages yet. So I guess, if you clean and threat it well, it will last you a really long time 🙂

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

Just make sure to take proper care with the acetone near your printed parts. You can create a mix of ABS and acetone to make the so called "ABS juice" to improve bed adhesion. For some other materials just using a glue stick (Pritt or generic brand) works great. Josef made a fairly comprehensive list of what you should use when printing which material here: http://shop.prusa3d.com/forum/print-tips-slic3r-settings-kisslicer-model-repair--f12/-material-settings-a-print-surface-preparation-1-7-t96.html

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

Honestly I do not see any reason to use any glue or ABS juice to make PLA stick to the PEI sheet.

Since I have my mk2, i never ever used anything on it, using various ABS, several PLA brands, ColorFabb PHA, PET, PETG (which stick just too well). The only time I had sticking issues were solved by adjusting the Z-Offset or using a proper clean using french "alcool à bruler" (which include some methanol, is a bit toxic, so I try not to use it too much).

Your PEI should be just fine, try to find alternative solvent to clean it.

I never dared to use acetone to clean the bed, because it's not so healthy and because it could be dangerous to manipulate, but I will give it a go, a good alternative here in France where IPA is not common to find.

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

I never dared to use acetone to clean the bed, because it's not so healthy and because it could be dangerous to manipulate, but I will give it a go, a good alternative here in France where IPA is not common to find.

Try a Belgian pharmacy website. I'm not sure they'll ship to France, but if I can order ADR goods like Rain-X to Belgium via Amazon.fr, surely they can send IPA to France? I would link you to the webshop I ordered mine from, but they appear to have merged and no longer sell the bottles. A different site does though: https://www.pharma-online.be/fagron-pharmawhite-isopropyl-alcohol-1l-fag (mods if this is not okay, please remove and let me know)

Combine with a microfiber cloth and it works great to clean the PEI sheet.

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

Heya, yes IPA can be hard to find in the EU in general I think,... damn overregulation...

I also go get it in a Pharmacy here in Luxemburg. No way to find it in regular commerce...
and yes IPA is a lot less smelly than Acetone...

happy printing 🙂
Serge

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

Hmm, I see a number of listings on Amazon Germany: https://www.amazon.de/s/ref=nb_sb_noss?__mk_de_DE=%C3%85M%C3%85%C5%BD%C3%95%C3%91&url=search-alias%3Daps&field-keywords=99+isopropylalkohol

They deliver anywhere in EU, no?

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

I bought this IPA bottle on amazon, shipping to France.
https://www.amazon.fr/gp/product/B01675DLP2/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
Shipping was expensive but I definitely don't regret it. I have no longer adhesion issues. I haven't tried "alcool à bruler" but window cleaner didn't work for me.

I've already changed my PEI sheet once - the first one was ruined with nozzle crashes and struggling with removing sticked pieces from the bed. It was not very difficult following the guide but it was not a very pleasant experience either so if a bottle of IPA can avoid me damaging my PEI again with too strong adhesion issues, it is worth it !!

Re: Does anyone here ever replaced their PEI sheet on the heatbed?

Window cleaner make it worse after some time.
I use IPA, which I bought from the online shop of "Höfer Chemie" I bought 6x0.5l of 70% IPA in handy spray bottles.
They also have 99%, but I think that's not necessary.