How to determine the shrinkage rate of your pottery clay

[@itsclearasmud7718]

I'm looking for a lost letter B if anyone finds it.

[@sarahjarden8306]

Thanks Jeff, this has opened a whole new way of thinking for me. I'll have to get a note book and pencil!

[@itsclearasmud7718]

Its a discipline. And sometimes those are hard to develope with consistency That being said the rewards are immediate and long lasting. It took me years to figure that out and soooo much of what I did is lost to me now. And taking videos and pictures stored on my computer in a master file with each addition renamed to the corresponding number in my journal is amazing.

[@cottonrosescrochet3232]

Great insights, thank you for giving this helpful information.

[@ingegerdandersson6963]

I love that you use the metric system.

[@darrellmelton1215]

This is great! Loved the video. It was so much more than just calculating shrinkage.

[@ingegerdandersson6963]

This is gold!

[@bagelm]

Love your videos Jeff, so so helpful many thanks!

[@judgetoogood1033]

Thank you…😊😊😊

[@itsclearasmud7718]

@@judgetoogood1033 thankyou for watching.

[@StevenfromTX]

I'll be doing some art with concrete mortar, using the clay to form the mold. I can imagine a lot of ways this information could help. Especially in addition to the video about making a mark. I've thought about different materials, most would be expensive or difficult; but clay would work great.

[@itsclearasmud7718]

Ive though about doing some concrete planters. Chicken wire ferro cement style in a plywood mold. I noodled on doing a decorative frieze in a strip around the top by making a plaster mold of the clay original to make a repeating decorative tile. Letting those tiles harden to leather hard and then stick them to the ply mold. After the concrete is cast I'd peel or wash away the clay leaving the relief in the concrete. Clay could also be mashed and carved on the entire ply mold. With the wire cage installed and then poured; the whole concrete planter could be relief. Good luck,have fun.

[@itsclearasmud7718]

You might give paper clay a test. Or hair of the dog with additions of nylon fiber. The chop used in concrete slabs. I can see that reinforcment helping against the force of the concrete as well as shrinkage.

[@tegannottelling]

I really like your channel, Your knowledge is great. Watched several of your videos. You have a lovely speaking voice and a great way to explaining things. Would you mind if I offered a little unsolicited advice? (Ignore the following if you do mind) You have a great knowledge base, you don't need special effects or whatever the intro is, sparklers etc. Remember, the goal of the introduction is to capture the essence of ceramics, showcase the craft's tactile nature, and ignite viewers' curiosity to learn more about the art form. The visuals should complement your chosen music and contribute to a serene and engaging atmosphere. Your pottery is obviously well practiced and I would imagine beautiful from what little I have seen of some of your more ambitious quick flashes of finished products. While I don't mind a good guitar rift, I'm not entirely sure it fits with the subject... For an introduction to a video lesson on basic ceramics for example, you'd want music that is calm, soothing, and perhaps a bit reflective to create a comfortable and focused atmosphere. Here are some music suggestions that would go well with your video lesson: Acoustic Instrumental: Gentle acoustic guitar or piano instrumentals can provide a tranquil and introspective vibe, setting a relaxed tone for the lesson. Classical: Classical pieces like Erik Satie's "Gymnopédies" or Claude Debussy's "Clair de Lune" are known for their gentle and contemplative qualities. Ambient: Ambient music with soft synthesizers and minimalistic textures can enhance concentration and create a calming backdrop. Nature Sounds: Consider incorporating sounds of nature, like flowing water, birdsong, or rustling leaves, to evoke a serene and organic ambiance. World Music: Soft traditional music from cultures known for ceramics, such as Japanese or Chinese flute music, can lend an authentic and cultural touch to your video. Minimalist Piano: Pieces from minimalist composers like Philip Glass or Ludovico Einaudi often have a repetitive and meditative quality that could work well. Folk or Indie Folk: Folksy acoustic tracks can infuse a sense of craftsmanship and simplicity, aligning with the hands-on nature of ceramics. Chill Electronica: Down-tempo electronic tracks with a chill vibe can create a modern and smooth ambiance for your video. Remember to keep the volume at an appropriate level where the music doesn't overpower the instructional content. The goal is to enhance the learning experience without distracting from the information being presented. Anyway... your channel you can certainly do as you please but as you did ask just after the into to leave a comment etc and music choice is often overlooked. Did I say I really enjoy your videos because I totally recognise your talent and skill and I'd love to learn everything you have to offer.... and I'm subscribed. If the above is too much I do apologise for butting in with my 2 cents worth. PS love the Outtro music and the pic of your pup is cute too

[@itsclearasmud7718]

Thanks. I never knew what I sounded like until I started recording these videos.

[@itsclearasmud7718]

You should check out Florian Gadsby. Smooth smooth, smooth. I think you will like him.

[@NotbecauseIcoudnt]

Given that you know the shrinkage rate (10%), if you want to have an opening of 4 cm for a teapot (like yours) after glazing and firing, would you throw the pot to be 4 +10% = 4.4 cm? The question intends to ask if, in your experience, the shrinkage rate works equally regardless of the shape of the piece.

[@itsclearasmud7718]

I don't think shrinkage is universal. For example, I have noticed a difference in shrinkage between the opening of the cylinder and the height of a cylinder. Water content also makes a difference. So each clay body and throwing style has what I've outlined in this vid as a," rule of thumb". You will work out the details as you go. When making a lid I can't tell you how many of mine have failed because of glaze thickness and a small amount of deflection or warping of the opening. So my basic rule, especially in production work is to make my lids with some slop. A 4% added gap might be perfect; but then there is the lid design to consider. As in the tea pot example I make my lids with a long throat that extends from the lid, about two inches into the tea pot. This allows for a loose lid to navigate around the restriction caused by the glaze at the opening and any deflection. But even more importantly when you hold a mug in one hand and tip the tea pot to pour with the other; the lid cannot fall out of the opening due to how far into the pot the lid extends. Lid designs, where the edge of the lid fits snuggly into a thrown or trimmed gallery is generally less forgiving for size and warping; you will have to be spot on. Very often potters apply alumina or wadding, or both in the gallery to accommodate firing the piece with the lid in place. Again, I have had jillions of pots that I was unable to get the lid off due to shrinkage. I think as potters we often stride to make thin pots with tight fitting lids. I abandoned that at some point for good pots with enough thickness to be durable and comfortable to use, and lids that work effortlessly and don't rattle around, " too much". Good question and good luck. I hope this was helpful; don't hesitate to ask me anything. JRP