Molding and Wax Injection for Lost Wax Casting

hey guys and welcome back to another video for today's video we're going to continue with our series on how to do lost-wax casting and so we're going to be doing the molding and injecting process this is basically the most important process or arguably the most important process in lost-wax casting and casting in general because this is how you're going to be able to make your multiples for your products so Dan already has the ring that we're going to be showing you today all screwed up here and I believe this is in brass or bronze rod and from here we're going to mold this and then inject its duplicates so let's jump into the borscht and dance kind of you showing you how to mold it and then we'll come back to me later and I'll show you how to use this to inject your molds hey guys so this is what we're gonna be molding today this is a sterling silver ring that I've attached the a bronze sprue rod to and we're just gonna jump right in so what we're using is no shrink pink by cast although and it's a natural rubber material and as the name suggests it is it has no shrinkage so some of the other ones that they offer they they say it has like a one percent or two percent shrinkage rate and you know you kind of have to think about that if you're gonna be molding you know a size 8 ring or something then it's gonna end up becoming more like a size 7 and 3/4 or something like that so this stuff it's it's really good it's it does require a very very exact temperature to vulcanize and in that temperature is 310 degrees Fahrenheit and yeah aside from that I I love this stuff this is the only stuff I actually used and I've had really good success with it so this stuff comes in 1/8 inch sheets and as you can see I'm cutting it with a clean pair of scissors it's very vital that you keep everything clean with this stuff so I'm avoiding touching the the flat surfaces with my my fingers because you know natural finger oils will contaminate it and it'll it'll keep it from adhering so what the vulcanizing process does is it of it cooks the rubber and it here's all these layers together into one piece so as you can see I'm pushing all the edges together making sure there's no bubbles in between because those will they won't necessarily get to get worked out in the in the process and yeah so this mold frame that we're using is 3/4 of inch of an inch thick and as I said before these are 1/8 inch sheets so what we're gonna do is use three pieces on the top and three pieces on the bottom and this stuff here that I'm using is a mold separation cream there's two ways that you can do molds and one of them is with this cream stuff basically what it does is it keeps the two pieces from adhering if you've ever done any sand casting you know that you kind of use the use the talcum powder or baby powder or whatever you use to separate the two halves this is the same principle it's just kind of like a talcum powder in a cream form so you can get it in all the little nooks and crannies something else worth noting is this is the bottom layer of the mold sandwich and this is what's going to hold the bronze or rather this is what the bronze fruit rod is going to sink into so you can see that little bend there that's gonna go into the the cream side which means that I won't have to do any cutting whatsoever it's gonna kind of fold over as it expands in the vulcanizer and all of that will just become free and it won't have any any cutting necessary at all so I've slipped the this mole or this model into the cone and what that cone does is it just creates the the shape of the nozzle for the wax injector and that just keeps everything nice and airtight when it's all being injected with the molten wax so because this doesn't require any cutting whatsoever I'm gonna be using mold locks and mold locks are these little punched out brass things and what they do is you just kind of stick them in the corners or literally wherever you want and they mold the rubber during the vulcanizing process into a small cone which then connects with the top mate of the mold and that keeps everything all nice and aligned properly the when you do the the cutting process there's there's a good chance that you'll be using a scalpel and what you do is you go in from the sides and you kind of have to do some tricky maneuvering and cutting of these little nodules and they're great that either method is fine I haven't had any real trouble with these they work just as well as the as the cutting method if not better because they're there's so much simpler and a little bit less time-consuming and technical so we're just gonna fast-forward through this next little bit because you've already seen what it's like to put together one of the halves that's pretty boring but something to note is that I'm putting two of the smooth sides together because there's one side on here that's got a diamond texture on it and sometimes not often but sometimes the the diamond can can impress into the mold itself and you can get a light impression on the ring which we don't want so I'm just going to put a little bit of pressure on this sandwich set everything so it kind of makes an impression and then carefully put it back or put it into the the vulcanizer which has been preheating this entire time and make sure it gets pushed all the way in because the the outer edges can be a little bit cooler so I want it to be nice and even and hot throughout on these older machines you can see this is pretty aged sometimes the top and the bottom platter isn't quite the same temperature so at about 20 minutes I'm gonna flip them and do another 20 minutes so here's a better angle of the pressure being put down on to the mold the the rubber itself during this process is gonna kind of pancake out everywhere it'll kind of spread out to the sides and if you don't have anything in that hole that will come in like it'll it'll Spaghettio that hole so um we're gonna take the pressure off turn the Machine off I'm gonna pull it out with pliers because again it is 310 degrees Fahrenheit it's very hot and put it onto the rag which is going to protect the finish on my wood tabletop and the these steel plates they don't really stick they just kind of lightly adhere and they pop off without much effort but but again be very careful they are hot so I'm just gonna take the plates off put them back in the vulcanizer and let them cool off naturally with the machine at this point this is kind of where you'd want to take professional advice and maybe let it air cool by itself but I'm impatient and for the sake of the video I'm just gonna pop them out by pressing with the rag on the side that has the least amount of spread out material and then pop the the mold frame back into the the vulcanizer with the rest the the extra material on the side is kind of a guarantee that you've got enough material to or rather you have enough material spread out internally and that's basically just filling in all the voids and all of this stuff can just be cut off with a pair of scissors and that you can write on this rubber with with a sharpie or a pen or something just to mark it and make sure it's all catalogued accordingly so you know what's in what so the molds all nice and cleaned up now here's the magic of this separation cream right here you can see it peels apart like a banana it requires very little effort the you can actually like you know leave a spotlight on the very end there and kind of make like a flap if you wanted to that's entirely up to up to you depends on the design really I did put the mold locks on the wrong side I put them on the separated side which means that they came out the way they did but not the end of the world I can always just slot them back in and it shouldn't be a problem so this is kind of that thing I was talking about by putting the sprue rod on the the separated side made a nice little release but you see there's some extra rubber that I want to remove so we're gonna go over to the soldering station and this might not be the most recommended thing but it does work wonders and yeah so I'm gonna use this broken file which the the handle is approximately the same size as my sprue and under ventilation very important because this stuff really stinks when you press it on I'm gonna literally melt the the rubber away I think what happened is there was a little bit of a gap between the the sprue and the cone and it just made a little flap that would inhibit the wax as it's injected so I'm just gonna press this hot piece of metal into the rubber and it just kind of melts away in this gross smelling beige fluid stuff and it wipes off with a cloth no problem this method might not be the the most recommended but it does do wonders it can save you a lot of time or or it can help you fix a mold that may or may not have worked out exactly as it should have so yeah we're just gonna take off a little bit of this material and spread it open wipe away that extra rubber and we'll give it over to Shannon so she can do the injecting the mold for our ring from Dan all nice and new and it's bent out so that the wax will release nicely we're going to launch in to how to inject it so the injection pot is all ready to go the wax is nice and warm I usually have the pot around 200 degrees and when I'm doing these molds I usually have around three molds ready to go by the time I've done the third mold and injected it the first mold has cooled down and the piece is ready to take out like the piece you can see here so as probably has been said before in the video these are vulcanized rubber molds you can also get a two-part cold setting molds called liquid cast there are others probably available out there on the market but that's what these are made out of and they're great for when you're dealing with a wax master like this one is or possibly an organic item that can't withstand the heat like the other mold watts which was a bear claw if you want to see how we make our liqui cast pour molds just cut leave a comment down below now let's get into doing our first injection so we're gonna be taking a plate and putting one on the top in the bottom these plates here are a little bit thick but they get the job done and how it would DIY you never know and we're going to be taking a clamp that has parallel jaws on it so we can get a nice accurate and even pressure all the way along and we're going to be clamping that together I have to do it on the table because these clamps are a little bit tough these are actually from an old GoPro but there are specific clamps out there for this set up we just don't have any at the moment so I'm going to be purging the wax that is actually in the pump at the moment so I can get some slightly hotter wax to be able to inject as you can see there you can actually get quite a lot of pressure even though it's just a hand pump system so I usually pushed on the plunger until I feel a change in pressure and from there I will still apply a slight bit of pressure just to keep the wax pushing into the mold after you've held the pressure for about 10 or so seconds you're going to want to take the mold away and set it upside down with the inlet facing upwards there's no risk of the wax coming back out but you certainly don't want the wax to kind of pull away for your details inside your mold with the ring injected I'm going to continue on injecting my chain links from the other molds so the wax we're using today is ferrous turquoise wax this wax is a medium hardness box so it's pretty tough we've been doing a lot of chains lately so we put this in so we don't have to worry about breaking them when we're taking them out of the mold or working with them this wax also has a release agent in it so that means it's easier to take from the mold you can get waxes that are specific to carving that are higher temperature melting waxes so they're good for filigree and really dainty models so basically you need to tailor the wax you're using to the project that you want to do so now that the molds are all injected I'm going to go back in and check my first mold and you'll notice of course that when the wax is solid and cold it's going to be a brighter and more opaque color or is when it is still a warm it's going to be a darker and more transparent to kind of look to it so now that it's I know it's cooled down I'm going to start to open it and see what it looks like so I'm going to start opening the mold by lifting away at each of the corners generally some molds work best if you open it from a specific direction depending on how you put the model in the mold and that's generally the side that we put our label on so as you can see I'm pulling at those corners and then go slowly going to pull the top off revealing how well our wax turned out if it's not that great you can always just pull it out and tuck it back in the injector but as you can see it turned out pretty well so I'm going to put a quite a bit of pressure on each of the sides pop out the sprue and then pop out the ring itself so if you want to know how to sprue entry the injections that you just did or maybe some hand carved waxes we have a video on how do you do that already post it to the channel if you like this video please give it a thumbs up and if you like our videos in general please remember to click that notification bell we don't post all that often so it's going to come in handy again thank you guys for watching and we will see you guys next time

Channel: Clear Mind Jewellery

Views: 79,689

Keywords: Lost Wax Casting, Jewellery Making, Mold Making, Wax Injection, Casting, Metal Casting, How to Cast

Id: -JD0xUseP3w

Length: 14min 22sec (862 seconds)

Published: Fri Mar 08 2019