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Hi all, Second time posting here and I’m hoping you can help! Hopefully this is the right place to be for a troubleshooting question like this. Im currently working from a recipe for Val Cushing’s Cone 6 Porcelain Slip. grolleg: 15% tile 6: 15% Epk: 3% om4: 10% flint: 25% neph sy: 30% gerstley borate: 2% —————————— Sodium silicate: .0028% calgon: .0005% When I mixed this before, as now, I subbed the deflocculants with Darvan. I mixed it successfully then, but I’m currently have difficulty. I know that darvan generally subs for sodium silicate at 2-1, so bearing that in mind, that’s where I started. I kept adding darvan in small 5g increments up to 100g in a 10000g recipe. That seems like far too much, but maybe I’m wrong? I feel like I’m on the other side of that deflocculation bell curve some how and missed my mark. Every time I come back to the studio the slip is gelled thick but never settled and never develops a skin. When I’ve added more darvan, the slip temporarily thins, but seems to rebound to being too thick the next day. Can the casting process indicate overdeflocculation? If so, in what ways? What should I be looking out for other than settling and a skin in my bucket? Can anyone offer any advice on this recipe or deflocculants? I’ve been doing some hard research and testing and can’t nail it down. My current gravity is measuring at 1.71, so I’m hesitant to add more water, since according to some other online sources I should be aiming between 1.7 and 1.8. I’m wondering if I should throw caution to the wind and say “this slip just needs more water than most”. Ive mixed this slip before with great success two years ago. I have no clue what I did right then. Dumb luck haha. Any suggestions or advice would be greatly appreciated. Thanks!

Hello everyone, I am hopefully going to be embarking on a journey soon enough of selling some log cabins. I am hoping that I can figure out a way to make a mold of the design so that I will have an easier time producing them. Here is a LINK to some pictures of one. I am wondering if, with some modifications, a mold is able to be made of a complex shape such as this? The roof is separate and I would be making a separate mold for it. Are the amount of details added, such as the window panes and door frames too much detail for a mold master and would be better added afterward? The windows themselves would not be cut out yet of the mold master but is the hollow inside a problem? I am thinking since it is hollow than it would have to be a slip cast mold but since there are so many over hangs I am guessing it would not just slide out easily? Would a two piece slip cast mold work though - that is split horizontally? This way it just pops off? As for my slip cast mixing question. I've been doing some research and see that sometimes people say it has to be mixed for hours while other instructions only mix for 10-30 minutes maybe. Are hand drills with say a jiffy mixer used often and successfully in mixing slip or do industrial mixers need to be used? Thanks in advance for any advice and I hope this makes sense.

I have been given a 25kg bag of powdered porcelain. If I want to use this to make casting slip, what other ingredients would I need and in what proportion? Also, could I use it for throwing - if so, same question, what else would I need to add? I hate to waste a 'freebie' so would welcome any helpful comments.

Hi, I'm mixing VC vitreous white /\6 casting slip, which calls for 3.5% Darvan 7. Unfortunately I cannot get Darvan 7 any longer and was sold Darvan 811. I'm trying to find out how much DArvan 811 to use as it is "much stronger"....very vague. Research on the internet, and phone conversations with reps from the manufacturer (Vanderbilt) and Laguna haven't helped much as they say "to add little by little", "don't use too much", "wait at least 24 hours after adding Darvan 811, as it works much slower than Darvan 7". I have done all that but the slip still feels thick and almost gooey. I don't know how much Darvan is too much. Does anybody have had this experience, and found a solution? Vitreous white /\6 grolleg 25 EPK 25 Kona F-4 30 frit 3124 4 flint 16 bentonite 2 H2O 40-50% darvan 7 3.5 grs darvan 811 ????? Thanks, raymonde