Da clumsy noob has PVA and humidity images to show changes

[kmanstudios 1,120]

OK, PVA seems to be the first thing that really gets on people's nerves. Depending on the brand, environment and a host of other issues, it can be a real pain to deal with. My PVA setup is using Matterhackers PVA for the most part. Why? Cheap and it dissolves much quicker. I do have Ultimaker PVA waiting for when it is just the right thing to use. Its more solid structure can be very useful for certain types of geometry.

 

The Matterhackers PVA is a bit more caramel in color and never is crystalline looking like the Ultimaker PVA. It also dissolves a lot quicker with less of a gooeyness to it. It also makes a real nice PVA slurry when recycled. Very much like wood glue where the UItimaker PVA becomes alien snot or xenomorph drool if ya knows whut I means......

 

For this though, it can show the difference in how moisture, no matter what you do will invade the material. My setup uses the Polybox to keep the materials dry on the spool and the PVA is run with a Bowden tube from the Polybox to the feeder to minimize contact with air and moisture. In the pic, you can see though, that the PVA will still get moisture in it. And, we have had a relatively dry winter here in NYC.

 

I ran out of PVA while printing and used change material in the middle of the print to put on a new role. I did use the same brand. This allows you to see the difference of a PVA that has been in use for two weeks and the brand new, freshly opened PVA. Not only is there a color difference with the new PVA being a bit more white (But still a bit less than actual white) and how much more solid it is. The older PVA tends to be a bit more cobwebby and has a wispy stinginess to it also. While still being a solid support, you can still see the difference. This would be greatly magnified through the lack of a drybox solution. It is its own KT boundary.

 

By using the Polybox, or any drybox solution, it does extend the life of the material without requiring quite as much cleaning of the nozzle interior.

 

[Bossler 8]

Reg. Polybox - what does your humidity-display tell ya?

Mine always goes not lower than 20% with fresh descant in it...

While the room is around 42-46$`% humidity...

[kmanstudios 1,120]

Right now, 11% on both of them.

[Bossler 8]

Hm, strange.

Maybe the humidity meter is a bit off at my Polybox.

The silica is dry, that's not the problem.

I did even try with additional silica but it does not go below 20°... 

[kmanstudios 1,120]

That is strange. I substituted the silica that came with it for color changing silica just to make sure things were dry. I do use it in conjunction with their supplied desiccant.

 

Edit: Although it is still way below the recommended humidity levels (50% or less) I would ask Polymaker about it. That usually takes about an hour to get it down to expected levels as advertised, but I have never not had it meet that level.

Edited February 6, 2018 by kmanstudios

[Bossler 8]

Compared with another humidity meter.

That one says "low". Which means <20°. So the meter in the polybox is at least "a bit" off...

[kmanstudios 1,120]

56 minutes ago, Bossler said:

Compared with another humidity meter.

That one says "low". Which means <20°. So the meter in the polybox is at least "a bit" off...

Yeah, it seems the hygrometer is off and you should contact Polymaker about that.

[Bossler 8]

I just treat "20°" as a good value and good it is;-)

I have also replaced the silica with some color changing so I guess I will know when it's time to dry it.

 

By the way - which silica do you use? The one I have inside the box right now was quite expensive and I am looking for "bulk material" to build
dry boxes myself.

[kmanstudios 1,120]

I just got some stuff from Amazon. Seems to be working as I did have to dry a bunch a couple of weeks ago and the color changed back. I use it as the indicator, but as I said, I do use their supplied massive packs to help.