Pugging Porcelain- Achieving a decent reclaim clay with pugmill

[Megga]

I have an old Venco de-airing pugmill, with an aluminum barrel. I'm starting fresh once again with an empty, cleaned out barrel. My intention is to pug my huge pile of porcelain reclaim clay all at once (over a few days, perhaps). Then I should just clean it out, because when leaving clay in it, I've repeatedly failed to get back to it in time.

 

I use ^6 porcelain PSH 910. Over many years I have never yielded reclaim clay that was a pleasure to use. I've always restricted it's use to a few items where the imperfections aren't as big an issue. But I feel like I should be able to do better, deairing pugmill and all.

Some of the challenges:

-When throwing, materials settle in the throwing water and form a hard lump in the bottom. (Primarily talc?) I've tried both adding this to the reclaim bucket (get dried gobs of material- but I could possibly deal with this more effectively in the future) and leaving it out has been my latest strategy. 

-As seems to be more common knowledge now, the aluminum barrel and porcelain clay react over time and form clumps of salts (?) that make hard horrible bits in your clay. A large part of my reason to try doing a big batch at once then clean it out.

-Getting the PSI high enough to de-air the porcelain is difficult

-The clay comes out short. 

 

The bags of clay have been sitting around for a long time. Any additives that I try now to improve the plasticity would be added as I pug. Ideas I'm considering:

-Adding some vinegar, because it would swing the alkalinity to slightly acidic, which would draw the particles closer together and possibly improve the plasticity.  

-I could mix some bentonite and water, and roll the clay in a bit of that "snot" before pugging?

-Epsom salts in the clay (straight from PSH) have not had good results for me. 

-A potter I worked for years ago used to mix her boxed clay 1:1 with the reclaim. But I'm nervous that the result would lower the quality of the boxed clay, more than improve the reclaim? 

 

Any brilliant thoughts and suggestions are appreciated. Cross-posting

Edited June 16, 2022 by happy_pots

[Callie Beller Diesel]

Moderator note: 

As this thread has been cross posted, if you want to make any suggestions about reclaim and chemistry, there is a thread started in the Clay and Glaze chemistry section already. Here’s the direct link  for anyone interested in that side of the conversation.

I suggest for purposes of continuity that responses in this thread address the Proper Care and Feeding of the OP’s pug mill.