Reclaim waste clay into Casting Slip for ceramic production.
ฝัง
- เผยแพร่เมื่อ 30 พ.ค. 2024
- Mixing dried clay pieces with water to create a fluid, usable casting slip with white earthenware clay.
Learn how to calculate your slip's Specific Gravity and understand when to add deflocculant to the mix in order to get to a workable consistency. - แนวปฏิบัติและการใช้ชีวิต
To hell with skillshare and undemy and whatnot, this guy is an actual instructor, I've learnt so much from this video, thank you!
Glad you enjoyed it!
Your explanation of the target weight for specific gravity was a game changer for me. Made everything easier... I didn't need to get a precise 100ml beaker, I could do it with materials I already had on hand. Hugely helpful, thanks again!
Glad it helped!
Thank you so much for this video. It’s such a great resource for the ceramics community. Whenever people have questions or need help with their casting slip, I refer them to this video because it’s so well done and simply explained. I had also never seen anyone use the “any old bottle” method of measuring specific gravity, and now I use that in my own practice.
Thank you!
You are so welcome!
Looking forward to giving this a go.
Thanks for the explanation. I loved the sheep!
What a wonderful video. Thank you so much. So many times people try to dumb things down, but I really appreciate the in depth lesson!!!
Thanks for the lovely comment!
I have been slip casting for 3 years using readymade casting slip. I have moved to Scotland where shipping is very expensive so I have bought dry pellets. This video have given me the confidence to learn how to measure SG. the best video i have seen- fully explaining. THANK YOU !!
I'm glad it was useful!
Thank you, so much for posting
Such a well explained video - thank you ! I'll be saving this to use again and again
Thanks!
Thank you - great teaching 🙏
Thank you so much for explaining everything in such a clear way :)
You are most welcome
Thank you so much for this! I initially watched some time ago and have just gotten into the practice of accumulating trimmings, organizing buckets etc. My trimmings have been slaking for several days and vigorous mixing is only resulting in clumpy mud. Came back to rewatch and see now i should likely add a touch of sodium silicate even at this early stage. Gonna give it a go and move forward! I truly appreciate your making this video. It is a much better explanation than most and have saved it for my future reference! Cheers to you!
what a lovely comment, thanks!
Thank you very much, you made it easier
You're welcome!
Very helpful video thank you
So nice of you
Thanks
No problem
Thanks for the informative video. I tried this before from the video method and it worked like a charm. However, I recently tried making a slip with a new clay body. I added a little bit of sodium silicate, and it didn’t work as intended. It made clumps. I let it sit for a day, and now it’s a normal texture for an over-deflocculated slip (re-flocculated?), with a thick skin on top.
I read that sodium silicate is better to dilute 50/50 with water, so i would be careful to dilute it. I also see washing soda in a lot of recipes as well.
adding too much deflocculant can have an adverse affect on the slip, making it get thick and even separate.. go easy!
Very helpful video! I just can't get the ratio right. It will weigh less but if it sits a little it thickens up alot!
Thats normal. You can get the slip weight perfect, flowing perfectly, then check the next day and the weight may not have changed but the viscosity is likely to have changed, which is when you need to add deflocculant.
This has been very informative and as I already had a bucket of slurry from throwing on the wheel I have tried this out rather than using the dry clay pieces. Unfortunately my slip weighs too light and I’m struggling to correct it. Is it because of the slurry, which was very thick and gluggy when I started to use it, rather than using the dry clay added to water? I would have thought it would be the same? Can you advise?
If it is too light, you'll need to add more clay. If this makes it too thick, add a deflocculant to thin it down.
Thanks man, that was an excellent lesson. I was wondering though, because this reclaimed clay had the perfect amount of deflocculent before it dried out, would you not run the risk of easily over deflocculating it by adding more sodium silicate now? I would have thought that all it would need was water, although you prove that not to be so. That's curious.
During the casting process the effect of the deflocculant reduces, even a well balanced flowing slip left a few days can need adjusting with a bit more deflocculant. If you weigh your slip and it is still too thick to cast, then there is no question you need to add deflocculant to make it flow.
@@HobbyCeramicraft Between me writing my last comment and you writing yours, I managed to make a slip from scratch and made my first kiln load of slip cast wares, which is exciting. I had some time to think about things in that time whilst recycling some trimmings and having to add darvan exactly as you said. The thought I had was that the deflocculent is an electrolyte that causes the clay particles to repel each other. The slip becomes runny but syrupy, which is also curious. I assume that repulsion is caused by a charge and that charge weakens over time or when the trimmings dry out (because water is ionic). But also wonder if it it's possible to reintroduce charge without adding more deflocculent. For example if the mixer propeller or impeller was of a clever design, perhaps based on some of the principles discovered by Schauberger, a great yet unconventional inventor who designed implosion based, charge inducing machines.
Thank you so much for this video. I am definitely going to give it a go now with much more confidence than before. I trust that I can do a good enough job and not waste tons of time of trial and error. Your information is worth gold to us. Does the same ratio work for stoneware clay? A huge thank you for what you do. It is very inspiring.
I use the same ratios for reclaiming Stoneware slip, however the amount of sodium silicate (deflocculant) will be different. Stoneware slip needs more deflocculant than earthenware.
@@HobbyCeramicraft that is so cool to know because I have made a mould and I will be using the slip from our wheels to pour soon. Thank you so very much for all that you do all of you at HobbyCeramiCraft. I really appreciate being one of your clients.
EXTREMELY informative! I was given several pounds of raw clay just dug out of the ground by my brother-in-law. I had in mind of just adding water to thin it to make slip. Very glad I watched this to understand how to properly make the slip I need - I would have hated wasting this on inferior or unusable castings. Any suggestions on how to figure out the firing temperature (cone) the clay needs to be fired at?
You'll need to do some test firing. Finding a temperature at which the clay is stable may be relatively simple.. fire to 'x' if it is ok, refire to 'y'.. etc.. however finding a glaze which fits onto the clay may be a bit tricky. Good luck though.. if its a nice colour you may be ok just adding some basic colours and not putting glazes on, dodging the COE fit issue with glaze.
@@HobbyCeramicraft - what does the COE fit issue mean? I am a total newbie at this.
@@jmortonsalt Coefficient of Expansion. How much a material expands and contracts when heated and cooled. This is why you have glazes for certain clays, designed to expand and contract at similar rates to the material they are put onto. If the glaze contracts when cooling more than the clay then you get crazing which is a spider web of cracks in the glaze surface. If you have the clay contracting more than the glaze then you get 'shivering' which is where the glaze literally detaches in a sheet. Get it right, happy days!
Can you use the slip right away after mixing?😊
تحياتى العمل كان صعب حتا وجتك استمر
Thanks for sharing your knowledge! Just one question: why can you only use 25% reclaim? I only want to slip cast to reuse my wheel trimmings, so ideally I'd use 100% reclaim.
Just habit. Helps average out any miscalulations on reclaiming ratios if you mix it with a decent amount of premixed new slip.
Why would you only suggest using 25% of reclaimed slip in the 40 gallon tank? I saw in a previous message that the other 75% should be pure slip, so how would you go about making pure slip? Just use clay straight from the bag?
Ps - your videos are so incredibly helpful; thank you.
Aw, thanks! You can make slip from regular clay, just don't forget to add deflocculant or you'll just get mud! I go for 25% just so I don't have to really think about measurements too much.. if the 75% is new and measured, then the other 25% can be off a little and I won;t notice!
Hello, i ve been watching your video, very helpfull thank you and doing it step by step by watching your video. My gravity is around; 1.69 and slip weighs lower then desired weight. So should i add more reclaimed clay in it?
That's not too bad, you can cast with slip at that weight, but if you want to add more clay, just remember it will need more deflocculant in order to flow.
@@HobbyCeramicraft ok i ll try thank youu
Will this process work with clay that was not originally made for splicasting? I reclaaim all my clay from throwing and what not and I am wondering if I could try out slipcasting by using those leftovers for starters by just buying a 10 euro bottle of sodium silicate...
I also make slip from regular wet clay. Oddly, making slip from blocks of wet clay is not as simple as from dry.. you have to really mix and mix to break down the chunks of clay to get a slurry.
Can you recycle your daily trimmings by adding water to them, mixing, check and adjust specific gravity and then back into to slip tank?
Precisely.
My problem is that my target weight was coming in low so I added a lot more clay until I finally hit my target weight. But now my slip is massively too thick. I have added sodium silocate but its still somewhat thick. Should I keep adding more deflocculent or can you add too much? I have put a fair amount in already because the slip was so thick . Did I do the wrong thing by adding a lot more clay to get my target weight? I appreciate your help
You can add too much sodium silicate. If you do, it can be tricky to pull it back so it is a good idea to add cautiously. To be prudent I would take a smaller quantity of the slip out and add sodium silicate to that and see if that makes a difference, without the risk of making a mess of your main batch.
Hi.. Thank you for this video.. I'm in Sri Lanka and I'm doing a project about the reusing of clay scraps. We are adding a little amount of scrap (29%) to the pure clay usually.. but when we add more scrap it is also take time to cast more than usual.. Can you give me any suggestions please..
Just make sure you check the S.G. The amount of reclaim used should not affect the casting time.
Hi nirmani . Can you tell me what material you use for slip casting please . waiting for your reply.
Qual é o material cor de chumbo que passa por cima da massa refratária?
Sorry, my translation of this didn't make any sense.. I have "what is the lead coloured mass?"
For ease, you need only fill a container to a specific measured level (say a line you draw on a container halfway) instead of filling it absolutely full. You can put in water to that level and slip to that level. You can also get a measured container that has pre-measured lines. Water weight is the basis of "gram" meaurements. 1 gram is equal to 1 milliliter of water. Therefore 100 milliliters should be 185gram or 500 milliliters should be 5x as much -- 925grams.
All good. The reason I choose a conical shaped bottle is that the top is narrow and it is easy to fill to exactly the same level each time. Whereas if you had a wide measuring container it may be a little more tricky to hit the same level, particularly if the slip was thick and not prepared to fall into a flat surface.
Hello brother, I want the mixture, the amount of water, the amount of clay, and the amount of silica, please
My recycled slipcasting gel very much in my molds even I have 1.8 specific gravity and good viscosity ? Sir how I can fix it thank you have a nice day
You need to deflocculate, also, you can drop the sg down a touch below 1.8 if you want by adding water, the slip will still work, albeit it will dampen the moulds a bit more.
Thank you
How do you adjust for low viscosity
If the slip weighs the right amount and is too thick, add deflocculant. If the opposite and you have the right weight but too thin.. then it is likley you have added too much deflocculant, which is a problem. You should put that to one side and as it ages it will thicken. While you make the next batch, add in some of the thinner slip as a substitute for deflocculant.
I always get air bubbles inside!! 😢
I have also just tried using dry clay pieces into water but still comes up with the lighter weight than the container/water net weight
I think deflocculant may be what you need..
Can you teach on how to make a mold starting from another mold?
Cast it with slip, and make it thick, then when you take the mould apart, you can cast plaster over the clay form and the other part of the mould, then do the other side.
@@HobbyCeramicraft I have trouble separating the plaster from the other side of the plaster. I've tried with liquid and solid vaseline, I've tried with dishwashing detergent, but the two halves always stick.
You really need "mold soap". I've been through a few and settled on the one I like, also, be sure you mix the plaster up to right consistency. If your plaster mix is too thin then it will not be very strong and more likely to leave chunks of plaster on the other piece.
Hard to hear you but great information
Sorry about that
Impressive bucket-to-bottle pouring technique! 😂
I know, right?
Hi sir . Hope you are fine . I searched about this project and came to your channel . going to subscribe it . Very informative video . I need this formula for one of my projects , don't know even abc of slip casting. Please tell me the names of the things and there ratios to make this slurry . Thanks in advance. Waiting for your kind reply
Thanks, is all the required information you are asking for not in the video?
@@HobbyCeramicraft surely I learned a lot from your video . 2 questions here : can we make slip from broken tiles having glaze on them??
2nd : can we make slip direct from clay ?( I mean without going towards recycled clay)
First question, no. certainly not if the tiles are fired, but even if they are clay, you wouldn't want glaze in the slip mix. Second question, yes. the recycled slip will be very similar to regular clay in that it will need water and a deflocculant in order to make into a workable slip.
@@HobbyCeramicraft thank you so much for your kind reply and knowledge. Stay blessed ❤️❤️
Love this video but it's kinda hard to hear you my phone is turned up all the way.
Sorry about that..
Hello brother, I want the mixture, the amount of water, the amount of clay, and the amount of silica, please
If you are making slip from reclaim the amount of water, sodium silicate, clay will vary from one mix to the next. Start by adding water to the clay you are reclaiming, then weigh the mix to see if it is too heavy or too light, then add water or clay to adjust the weight. If you get the right weight and its still too thick, then add sodium silicate. Try this video for some guidance on weighing a mix : th-cam.com/video/_dtVRNJkh4w/w-d-xo.html
hi I waste all my waste I didnt know u could do that cause u thought water would ruin my moulds.ty
Perfect! Glad this helped!
Hi looks good just can't hear you
yeah.. it is a bit quiet.. just find a peaceful place and block out the rest of the world to really get in the clay-zone when watching!