PVA not Sticking to PLA

[esteban-pacheco 30]

at the beginning the combination PLA/PVA worked like a charm, now im having adhesion problems (PVA printing on top of a PLA layer). is it related to hardware problems or is just the PVA filament is affected somehow by humidity (i store my PVA spool on a ziplock bag and TONS of Silica bags)

[esteban-pacheco 30]

maybe using Scaffold there more chances of bonding?

[flowalistik 178]

If you are already keeping your PVA spool safe (in a ziplock and silica bags), I don't think it's a problem related to that specific spool.

In my experience, PVA doesn't stick very well to PLA. The solution I found in my case was to lower the PVA print speed and set the extrusion to 125%. This means longer printers and using a little bit more PVA, but in my case it helped a lot. Of course, it depends on the model you're trying to print, as some geometries are more difficult to print.

What print speed and temp are you using with PVA? Ultimaker standard profiles?

[esteban-pacheco 30]

If you are already keeping your PVA spool safe (in a ziplock and silica bags), I don't think it's a problem related to that specific spool.

In my experience, PVA doesn't stick very well to PLA. The solution I found in my case was to lower the PVA print speed and set the extrusion to 125%. This means longer printers and using a little bit more PVA, but in my case it helped a lot. Of course, it depends on the model you're trying to print, as some geometries are more difficult to print.

What print speed and temp are you using with PVA? Ultimaker standard profiles?

 

yes im using standard profiles for PVA, that means in numbers : speed 60 and temperature 225 C,

which ones are you using?

[flowalistik 178]

For PVA I went down to speed 40mm/s and 120% flow. I kept the same temperature.

However, as I mentioned, it depends more on the model you're printing rather than the PVA printing settings, as a small flying support may break and transform a beautiful print in a mess.

[esteban-pacheco 30]

thanks, now it works better, but theres no other support material that can be dissolved in water?

i mean after all, is not so easy to print with PVA, and what i hate most is that i need to clean the nozzle so often! because it doesn't sticks properly, the nozzle catches the PVA that wasn't attached properly to the layer, and it stays there in the outside of the nozzle and it turns dark and sticky.

[flowalistik 178]

thanks, now it works better, but theres no other support material that can be dissolved in water?

i mean after all, is not so easy to print with PVA, and what i hate most is that i need to clean the nozzle so often! because it doesn't sticks properly, the nozzle catches the PVA that wasn't attached properly to the layer, and it stays there in the outside of the nozzle and it turns dark and sticky.

 

As far as I know, PVA is the only support material that dissolves in water. I've only tried Ultimaker PVA, but there are other brands that may offer different properties.

I'd recommend you to share screenshots of the sliced item in Cura. It may give us some clues on what the print does and we may find a solution for everything. Every model is really different, and PVA may behave in a different way depending on the support density, if there's a raft or not, etc.

[YvesRossignol 0]

Hi, i try to use pla and Pva but it never stick to pla. I used std procédure. It work well with nylon but température is more high. I have pictures but i dont Know how to send it on this forum.

I Will try your advice as read before.

[YvesRossignol 0]

Now i can send to you some images[/media][/media]

Thanks you for your help