I’m always fascinated whenever I see sneak-peeks of mold-making such as here on Lynn Fraley’s website. My curiosities have been further heightened by Barry’s casting my Babysitter model in an up-side-down fashion (which is actually right-way-up, as models are normally poured upside-down. Got that? Right! 
), he sent me this photo and ever since I’ve been pondering on the whole idea.
There are pros and cons to both ways of moldmaking but it’s something I’ve not tried yet… I’m pretty sure that if you’ve been following this blog for a while, you’ll know what happens next…
I did document this process on Facebook as I did it, but I felt I’d like to post the process here and bring all those pictures together with a more linear explanation of what I did and why.
So, in the picture above, I’ve made a start – I’m heading into new territory for me here, I’ve made two and three piece molds before, but always around a model say firmly on a base, I’m not sure at this moment whether my new mold will be a two-piece or three piece, at this point I don’t even know where the seams will go!
This is where I’m heading (photo below). The model is tipped forward at an angle like this as I want the air to find a way out of the mold when I pour the resin, so I figured the ears need to tilt downwards. I’ve also decided to go for the three piece mold as this model has quite a detailed belly and, being a broodmare she is all bagged up and I didn’t want to risk ruining these details. The legs would actually allow for a two-piece mold as she isn’t standing square, but my lack of confidence and the fact her tail is joined to the back leg lead me to the three-piece strategy. I haven’t had much sleep recently and have been dieting for my Wedding too, so I can honestly say my brain wasn’t working quite as well as it should have been throughout this process! I needed to get the original off to Horsing Around though so that they had enough time to make their mold and cast the copies so that I could tidy and post out some before the wedding in early May.
You can see below that the mare is all patchy again. Following the glamour shoot photos posted in my previous post, I smoothed her down again using fine sandpaper, 3M hand tools, recently discovered sanding sticks and various outer tools to get a nice smooth finish.
Ok, so I finished off smoothing the yellow clay – this process took a few hours, the seam lines have to be super-neat and the clay very smooth in order to get a tidy and successful mold, it is painstaking stuff!
The reason for the Lego will become clear later on – I could use a normal smooth pot but using the Lego allows me to remove bits as I need access to the tighter areas and built the walls up or down depending on which part of the process I’m at.
Ok, now for the brain fart:
Spot the mistake. Well, I knew it would be a three piece mold, and I knew I would have to pour each side then the centre part, but it didn’t occur to me until now (thankfully it occurred to me before it became a horrible problem) that unless all three parts touched the Lego, I wouldn’t be able to pour them!
That’s better! Now the blue clay reaches the outer edges. I made is as big as I dared to as I knew I would have to dig out the blue clay through the opening on the side of the mold.
So here we are with the finished clay sections (below). The reason for using the yellow and blue clays is so that when I’m digging away the yellow clay, I will clearly be able to see where to stop. The little dents and divots in the clay are to help the three rubber sections lock together when it comes to using them for casting.
Ok, ok, so I might have missed as I tried to take a photo as I poured, but the rest of the rubber made it into the box thankfully. As the whole Lego/clay assembly was too big to fit into my vacuum tank, I just vacuumed the rubber and then poured VERY slowly over the model, taking care not to allow any bubbles to get trapped. I first poured a small amount in and swished it about (slowly) to cover the whole thing, then as that started to gel I mixed up the rest and poured it over. This way I know that if there were no bubbles trapped in the first pour, the second pour won’t cause any as the runner touching the model (the most important bit!) doesn’t have bubbles in it.
Now, sadly I didn’t get any photos of the next bit. I allowed the rubber to cure (I use an accelerator to help make it cure quicker which is invaluable when a tight deadline is looming!) and then I turned the whole thing over and removed the yellow clay. Then I picked and cleaned all the little yellow dots from anywhere along the seam lines, which is a bit of a nightmare to be honest. Just looking at the Lynn Fraley link above I see Barry used cocktail sticks – I wish I’d have thought of that during this process!
You can see above that the divots I made in the yellow clay have caused raised bumps on the surface of the red rubber. I just used a paintbrush handle to make them and I probably made more than necessary (looking at Barry’s mold above), but I didn’t want to get this wrong and thought better to overdo this than underdo it!
So now it was time to pour the second part, I’m using red, blue and yellow here just to keep things simpler for myself.
Actually, in this phot (above) you can see one of my Kemper tools. When visiting Joanie Berkwitz last year I bought a small selection of these tools, they are designed for china production but I saw lots of resin and rubber uses for them! This one is the tool I used to make the linear groves that you can see in the blue clay above. The other tool, the dental one is my favourite tool in the world and it used for everything from sculpting to prepping, I can’t imagine life without it!
Ok, so yellow rubber cured - now the challenging bit, I have to remove the blue clay without dislodging either the yellow or red rubber. Where those seam lines are, the rubber mustn’t be pulled away from the resin model inside or it will make the edges rough leading to bad seams when casting.
After what seemed like an AGE, I got to this stage. It does still look quite messy in there and I wasn’t totally satisfies but time was ticking on and it was the best I could do. If I did this over I would definitely make that inner section much bigger!
Time for the final rubber pour (predictable, it’s blue):
Tada! After an anxious wait I very carefully prised the rubber sections apart (they grip on to each other when curing which is both a help and a hindrance). They sit beautifully with hardly any undercuts (not that it matters too much with rubber but it takes some risk out of the casting process) and, most importantly, the broodmare made it out in one piece!
Those of you who have made molds may have noticed one rather important defect in this mold; there is no pour hole! Not knowing how this process would pan out and not even knowing where the pour hole should go, I left this to the end as cutting out a pour hole is much easier than fiddling with one made in the wrong place.
I’ll move onto casting in another post as this model presents a challenge I’ve managed to avoid up until now… wire reinforced legs!
I’m happy to report that the broodmare is now safely in the hands of Mac and Vanessa at Horsing Around. Unfortunately, the hands that got her there weren’t so safe and, thanks to my midnight-sleep-deprived-don’t-know-what-I-was-thinking awful packing, she arrived with an ear break 
. So yesterday I took the afternoon off work and jumped in my little Smart car to make the 150 mile round trip to repair the ear (and improve on it, I’m pleased to say), so she is good to go as soon as Mac is ready to make her mold there. I’m also happy to report that I have already gotten one good cast from my three-piece mold and it is already with Deb Brown to be painted up as the first Guest Artist piece!
You may be a little confused over the two molds, I’ve not been very clear with you (or myself, for that matter) over how this edition will run, how many will be made, by who etc. I’m hoping to plan everything out properly over the holiday weekend after a few good night’s sleep and some proper meals. As soon as Deb has the model painted up for me and I have photos, I’ll post THE announcement everywhere (here, Facebook and on MH$P) and give all the info you need on her. One thing I can say for sure now is that she will be the same price as The Babysitter, offering in both RAW and CLEAN states and time payments will be offered from the beginning 
