Delft clay question

I seem to be the only one posting topics at the moment, and I apologize for that and appreciate y’all’s patience with me and your input. I have a delft clay question. I want to cast one-sided solderable charms, one side has detail and the other side just needs to be flat and unadorned. I’m going to make them and put the decorative side up on a large backplate around a bezel and solder it with the flat side down. They’re small, too. It seems kind of ridiculous to go through the whole process with the delft clay rings just to cast something small and one-sided. I’ve looked everywhere and can’t find an answer to this question so here goes. Can I just use one of the rings, pack it with delft clay, push my model down into the top of the sand in one ring on one side, immediately pull the model out, and pour my metal into the mold? Does that make sense? I’ll basically be making a hole in the top of the sand and just pouring the metal into the hole in the top of the sand, it won’t be enclosed or encased with another ring of delft clay but just hanging out on top of the sand. I have models piling up that I’m carving, but I’ve been afraid to just pour straight onto the sand and not through a pouring channel using both rings pushed together because I have no idea if there would be thermal shock from the molten metal directly hitting room temperature sand. If I can cast this way, it would definitely make my life easier, I just do several back to back scattered around the top of the sand all at once and get it over with. Thank you!!!

Give it a try. Your only loss will be some burned clay. I suspect that the melted silver won’t go into the detail as there is nothing to overcome its cohesive forces and drive it into the detail in the clay. You may have that problem if it is contained in a properly built mold too. If you have a hydraulic press, take a look at some of Kevin Potter’s shot dies or impression dies and see if there is something there that you can use. You can also try to carve your own die into a piece of soft steel. I am trying to figure this one out right now myself. Finally take a look at pancake dies on both Kevin’s and Dar Shelton’s FB pages. Good luck…Rob

2 Likes

I don’t have a hydraulic press… yet lol. It’s on the buy list, though. So I’m going to try to account for the shrinkage and gravity issue by making the wax models much deeper than they already are, which is fine, I’ll just add a block of wax smaller behind it with the TouchAMatic, shove it deeply into the clay, then pull it out. Then I’ll pour in a lot of silver very quickly and see if the gravity of the extra metal will force it all into the detail. Basically like you would in a regular delft clay casting just only using the top of the one ring. I haven’t heard of making your own dies by carving soft steel before, that’s new to me, I must look this up and learn how to do it! But there’s definitely no thermal shock associated with molten metal hitting room temperature delft clay, right? That only happens with certain materials like steel and graphite ingot molds? I always heat the crap out of my ingot molds because I have zero desire to get hit in the face with liquid metal, but for whatever reason that’s not a problem with delft clay?

Just pour it into the clay and see what you get . If you like it, great, if not, move on to another way that will put a little force behind the pour. I do suggest that you look into ways to create impressions from dies, shot plates and pancake dies (with or without embossing)
.

Craig Dabler has dozens of videos on YouTube,

3 Likes

subscribe lol. Thank you!!! I love info, this is great!!!

1 Like

I have done this. Yes you can. Only for the size of a coffee bean, anything more and you will have excessive over fill. Thus why most use both rings when casting. Forces the metal to a form. My husband says always work smarter not harder, how much time do you want to spend filing excess off to flatten it. You will have a hump of sorts. This is what you must decide. I hope this helps, God Bless :pray:

2 Likes

Awesome, I’m gonna do it! See, the things I want to cast are very small and detailed. The way I would have to put them into the sand to use both rings would cause the sprue to completely obliterate all of the detail on one side. So I would have to sit there and try to carve the details back in, most likely unsuccessfully, with an arsenal of burs.

Please let me know how this works out for you. Seriously I have done this a few times.

Many blessings,
Dana “DLR”

Your zero desire to get hit with liquid metal is your subconscious telling you to buy and use a face shield.
Intuition is the fast part of the brain outrunning the logic side.

2 Likes

Any face shields you recommend in particular? At the moment I’m wearing a dust mask and dust goggles—not exactly the best at blocking molten metal. I’ve been ok so far, no splash back, very careful and everything has gone smoothly, but it only takes one time of something going wrong. I value my eyes, I would like to keep them.

I use a Uvex Bionic Face Shield. looks like something out of The Expanse. Covers throat as well. Used for casting, grinding; anything with a wire wheel (potentially deadly needles). I used to have a really high end type that had a forced air supply and filters. Regettably, I sold it.

Good gear is pricy. As I once heard in a motorcycle shop: Yes Sir, we do have a $20 helmet. Are you sure you have a $20 head?

3 Likes

I have bought several at Lowes that work well. You can also find them on Amazon. I wear them along with a 3M dust mask when I polish…Rob

1 Like

I never considered the fact that a wire wheel can easily become a deadly ninja needle death stick. I just bought a bunch of wire wheels and just haven’t gotten around to using them lately. Thanks for making me think about this, I don’t really want needles embedded in my throat. And thank you for giving me a specific brand name for a shield, it’s good to be able to look at specific item specs to get an idea of what I need to look for!

Excellent, I’m going to check this out! I heard someone say they use the 3M mask with filters when working with patinas with strong fumes like Midas Black. I’m only using liver of sulfur at the moment because I’m really leery of toxic stuff and making sure I’m doing it safely. Any thoughts about the 3M masks and fumes?

Dana,
Re: Wire Wheels, you should also wear a Leather Apron when using Wire Wheels, as the little wires will eventually loosen and fling out and penetrate your clothing too - few things are worse than having those little wires stabbing you and you can’t find them to pull them out, also when brushing yourself off after using them, they will sometimes embed themselves in your hands and fingers! Dangerous little boogers, but they sure do a good job at what they do! Personally, I don’t wear a Leather Apron when using them (I get too hot in them), but I know what I’m in for and suffer the consequences anyway… :wink:
Jonathan

1 Like

I definitely always wear a leather apron, that’s one of the first things I bought. I need to get better face protection, though. I’m really glad I put off using the wire wheels and then read these comments. I didn’t even think about them breaking off and stabbing you. That could have really sucked. I’m not touching those things until I’ve got full body armor on now.

Hi Dana - you really must wear at least goggles when using a wire wheel. I failed to do that once when just stripping paint off a door handle with a small brass wire brush wheel. I got a single piece of wire embedded in the front of my eye (the cornea). That was unbelievably painful and I had to drive myself to the nearest emergency room with that eye weeping copiously and hurting like hell every time I blinked - you don’t realise how often you blink normally, until something like that happens! It only took a doctor a few seconds to locate the wire using a good lens and pull it out with tweezers and my eye was fine within hours but it was a nightmare experience up till then. Be warned!!!

4 Likes

I suppose this has been mentioned, but if you have several small items then do a two-part sand cast setup and have a sprue going to each one. Pour each one after the other, as you were suggesting earlier (I believe).
Also, maybe get fancy by combining the sprues, maybe to pour 2 or 3 at once.