Glass Base Plate Chipping

[Ciara 0]

When using an Ultimaker 2 Extended, the glass base plate is chipping whenever I print something.

The glass flakes off in thin layers and attaches to the print when removed. Any ideas why this may be happening? I have attached a photo of a chipped base plate.

[gr5 962]

What kind of filament?  This has happened to me mostly with PET and also with meltink brand PLA.

 

For small parts the solution for me is to just remove all the glue.  For large parts that really need glue I make sure it's a relatively thick layer of glue.  For me this is most likely to happen if it's a very very very thin layer of PVA.  You might think you have zero glue on there but there's still some left.  To get it all off you really need to run it under hot water for a minute and scrape it off with a scratchy sponge.

 

So I put maybe one stripe of glue stick on my glass.  Then spread it around with a wet paper napkin so it was very thin.  This was fine and did lots of prints.  Then a few weeks later (20 prints later) I decide it looks like a mess so I use a wet paintbrush to spread the PVA around more equally (making it even thinner than before as some of the pva left with the 20 odd parts).  THAT is when I started having parts remove glass.  The fix is to add more pva.  Or remove it all.

 

Note that glue stick, wood glue, hair spray - all use PVA as their primary ingredient.

[geert_2 176]

If you are printing PLA, you could try my "salt method". First, thoroughly clean the glass: you can use isopropyl alcolhol or whatever to remove oils and other dirt. And then clean again several times with pure warm water only (no soap, no alcohols, no thinners anymore, because soap reduces bonding and cheap alcohols or thinners might contain traces of oils, which also reduce bonding).

 

Then wipe the glass plate with a tissue moistened with salt water. Gently keep wiping while it dries into a thin, almost invisible mist of salt. This gives a good bonding while hot, but absolutely no bonding when cold. So the models come off automatically. For me this has consistently worked well for 2 years now. No need to take the glass out of the printer, just wipe again with a tissue moistened with salt water, and you are ready for the next print. Glass bed should be around 60°C. If cooler (e.g. 50°C), bonding is not good enough and the models may pop off suddenly in mid print. If hotter (e.g. 70°C) the models stay too soft, and may gradually peel off. So, (for me) the bed has to be 60°C +- 5°C.

 

But this salt method only works for PLA: it works excellent for Ultimaker and colorFabb PLA, and a bit less for ICE PLA. As always, with any new bonding method, stay around and watch what happens during the first prints.

 

For the full manual and pictures of the results, see my page (scroll down a bit): https://www.uantwerpen.be/nl/personeel/geert-keteleer/manuals/