Thank you so much 🙂

Thank you so much!

Glad you like them!

Thanks for watching!

Thanks so much. And that is great - I hope you find it to be a useful tool like I have!

Thanks!!

Glad you think so!

I've actually drinking out of that piece right now and the shadow lines created by the vertical lines are actually really fun. I'll need to play more with them to see what I like the most!

Thanks. I've seen a similar suggestion before. Can you say more about why it would only fill in the valleys of the 3D print between the layer lines and not also the parts protruding (the layers themselves)? (I have follow up videos using filler primer, and its the combo of primer to build up low spots, and sanding to take down the high ones that makes things smooth)

​@@PotterybyKenthi Kent, so what joe said was sort of true, it's the same principle to a clear coat of varnish on wood, surface tension keeps everything smooth, but another way of doing it would be to use abs instead, the only other requirement would be to use an enclosure to avoid warping, but once you have it you could vapor smooth the 3d print with acetone and it will leave it glass smooth

Thanks for the explination @ericsaul9306. My model of how this works is missing something for sure. So based on this, the outer surface, where the resin is, wants to be held smooth because of the surface tension, as opposed to it building up a surface with a more or less a fixed offset from the 3d print (like a paint would). I guess in this case getting the viscosity and thickness just right would be important.

@@PotterybyKent that's exactly right, too thick and it won't flow, too lean and it will just fall like water, also the best way to apply a coat is through a spray gun, as it will leave even coats, the best example I can think of are car paint jobs which leave the finish glass smooth

Thanks for shedding light on that!

Thanks for the feedback. I havent played with PrusaSlicer much but did see the option for altering the print seam lines. I like the idea of adding in patterns to the surface, but that might require going to multipart molds.

@@PotterybyKent Yes, print seam lines is exactly the option - but I think you'd be better served slightly sanding the part before casting - the seam errors will still be there but they'll be spread around the model at random points. Also, you printed the first demonstration the wrong way up, visible because the lines were coming of the model in the bottom indent. For the actual mold, it seems you flipped it over which solved the issue. However, the empty inside with the supports was probably slower to print than a solid model with moderate infill would have been, because the outlines take a lot of time to print. However, as you noted, the support tree turned out to be a handy handle to extract the mold. Something to consider would be to deliberately design a handle for that at the last couple of centimeters to speed up the print. As for multi parts - yep, I made a two part mold of a vase with a semi circular indent scooped out repeated like 32 times around the outside. Looked very involved, but I couldn't demold it without waiting for about a day when it had shrunk enough to let go of the molds, which wasn't what I had intended. Since then, I've been doing four part molds instead, but that comes with a lot of seams. I wanted to make thin throated vases, and that was never going to be easy with a one part mold. I'll be transparent any note that I don't actually have a pottery oven so all I do is experiment - but with actual plaster and actual slip. One more observation I'd make is that your molds are very thick - and I've seen people suggest that that's the thickness you should aim for. However, for me, plaster is fairly expensive and the molds take a lot of space. I suspect that the thickness is important if you want to make many pieces over a single day - the capacity for absorbing water is greater with greater thickness. If you're developing a shape, 3 or 4 cm plaster molds seems to be enough, though they're wet for the rest of the day after a single casting. Again, not suggesting you're doing anything wrong. Btw, I'm also a software developer - often involving coding in my more physical projects. Most such projects are an attempt to get away from the keyboard... How do you make the little texts on the bottom of your pieces? That must come in handy! cheers, m

The two scale prints I showed at the beginning were printed right side up with only a couple shells wide - so very fast since no support is needed (but yes with artifacts). For the actual print used for the mold it is printed upside down as noted so that there were no supports in contact with the outside surface. I've also found solid (or infilled) 3d prints can be extremely difficult to remove from plaster - so wanted it to be mostly air so it could flex (or be destructively removed easier) if needed. And yes, designing in a handle is probably a good idea! Yes, these plaster molds are all too thick for my liking. They are functional, but not ideal. What I am working towards is 3d printing an outer mold as well. I'm in the process of getting software to auto generate that mold. It'll probably take a few iterations to get it where I want - but step by step! My makers mark on the bottom is a stamp I created from silicone (cast into a 3d printed mold). I then use a stamp pad that has underglaze (instead of ink). kzfaq.info/get/bejne/ms9io5Shza-snIk.html

Thanks for watching and sharing! Indeed I was able to bump it up and the mesh was much smoother as a result (and that's the default in shape cast right now). I do want to get to more unique designs - I just need to find the time/motivation to wrangle the code!

Wow, very nice!

That is exactly correct. Those two requirements point in exactly opposite directions unfortunately! And that is why things like silicone and a rigid backer are often used. The other issue is you need the wall to also not be porous to plaster. I've settled on 2.4mm right now (0.4 nozzle size * 6) and it seems to be working well. The real trick was finding a way to slightly shrink the PLA part while inside the mold to release it. I have another video showing how to use a mixture of frozen alcohol and water to do that.

Thanks! Yes you can (although I havent tried much myself). The hard part is getting to where the bubble is inside the mold and then getting a good surface finish (as opposed to just cleaning the slip cast pot afterwards).

@@PotterybyKent Yes fair enough, things could get messy quickly, poking around with putty in the bottom of a pot. I see your molds have come a long way since this vid, I'm almost caught up. :)

Thanks for watching!!

For the finished pot? You just need to try it out with your slip and plaster (and weather!). Longer will be thicker and shorter will be thinner. That will let you dial it in. Also don't forget to take into account the clay shrinkage - it'll be thinner once fired.

I've actually stopped using anything on my 3d printed molds. A few videos later I show how I now get them out with a mix of frozen isopropyl alcohol and water. But for completeness, that was Murphys oil soap and any non-detergent soap would do something similar.

Thanks! I'm actually working towards some software that can generate the 3D files in a more automated way (so potentially you could make your own). Once I get that working, I might also provide some of my designs along with it. There's a link in the description to sign up for the waitlist.

That would be great! I signed up on your list.

Great!

You test with your slip and molds until you get the desired thickness. Luckily these attempts can be recycled indefinitely until you figure out the dwell time.

Sure. Something like this: amzn.to/3UwdnLo

As for why - you'd need to ask the creator! But yes, they are trivial to add. I usually put them in at the leather hard stage as it's easiest to cut the clay and not deform it. When it's bone dry there's a risk of breaking the pot. I've done a few after they've been bisque but you need something like a diamond bit to cut through then.

I'm pretty sure that is incorrect. Adding the organic supports doesn't require that much more material. Also, it is rather important for it to be hollow so that it can be removed from the plaster (as my followup videos show).

I'm not sure I'm understanding the question. If it is about my slip, it is a bit tan when a liquid and fires off white in the glaze firing as just the raw clay body.

Check out my other videos

The answer to your final question is yes that means it could be different between batches. So 10% +/- 2% means a given bag could have a shrinkage rate anywhere between 8% and 12% (which seems like a very high range!) I'd guess that means they have a lot of variation on their input ingredients they aren't controlling for. I had assumed (maybe incorrectly) that the range is much narrower, but that is likely highly dependent on manufacturer, or even the specific product line for the manufacturer.

One other thought is maybe the clay has a high range in temperatures. Like cone 5-10. It's possible some of the shrinkage variation they're accounting for is from that. If that is the case maybe the shrinkage would be more consistent given a specific firing target.

It's an original Ender 3

I don't think there is a very good way which is one reason I use 3D printing. I think the other common way is to sculpt or throw it in clay.

I could provide the one to my local pottery supply store, but it's not useful for 2 reasons. Plaster is big and heavy and would be crazy expensive to ship! And they don't have any right now since there are supply chain issues. Having said that, I buy USG #1 Pottery Plaster and it's distributed throughout north america. Not sure about the plasters used in other places.

For the 3D printed form, at this point I've switched over to an alcohol and water mix that I keep in my freezer. I put that into the mold which gets it cold and shrinks it just a bit and it pulls right out. Check out this video: kzfaq.info/get/bejne/a79hmbSk1s7Yj2g.html

@@PotterybyKent awesome! Thank you!

You're welcome!

You would need a multi-part plaster mold to create an S shape

It's expanded polystyrene foam. It's made as a sheet for insulation and is easy to cut.

Say more?

@@PotterybyKent love ur work

I have some old videos on my channel with more info on my kiln and using it

@@PotterybyKent okay sir thanks