June 2018

Blue Goo; What Do?

Hey guys! I’ve got a lot of new stuff coming up that I’m really excited to share! First, I’m pleased to announce that the third resin-cast Clariel has been purchased by a lucky Shadowhunter in Germany. I’ve already got the flap moulded, underside painted a nice reflective white, and adhered to the hilt. If all goes well, I’ll have it finished and on its way by the end of the week. Yay!

Secondly, I’ve been doing some weird silicone experiments in an effort to make my moulds with less silicone. That would cut down on my expenses and allow me make things for everybody at a lower cost. Yay! I really am trying, guys. I know cost is a factor for most of us.

If I had a big ol’ factory with assembly lines and million dollar injection moulding systems, I could be making stuff in bulk and charging less but … nope. It’s just me. Me and my own two hands doing the best I can.

So what’s this stuff? Same silicone, just thickened and painted on.

The thickener didn’t work so great so a lot of it oozed across the table.

Still, I got a decent mould of the rock I was using with a lot less material.

Clearly, more experimentation is needed. The mould ends up quite a bit thinner and it might be more flexible than I want it to be, but that’s okay! I remain stubborn and I will find a way to do this just the way I want it. 🙂

Lastly, I have a strange experiment in the works. I want to try a new way of creating a support structure for silicone moulds. Usually, moulds are clamped between two boards or a ‘jacket’ is created around it with either fibre-reinforced plaster (like a cast on a broken leg), or fibreglass.

I’ve experienced some problems casting smaller objects in resin when the mould jacket is made of plaster. Since plaster is made of gypsum, and gypsum has a verrrrry low thermal conductivity it takes a really long time to heat up or cool down and usually feels cold to the touch. My resin needs a certain amount of warmth to set properly, otherwise I get uneven curing.

I would happily make my mould jackets out of fibreglass, but I don’t want to work with glass fibres. They’re nasty things. Irritate the lungs, irritate your skin, and just generally get everywhere and make a nuisance of themselves.

I could use burlap or similar cloth instead of glass fibre and I actually tried to do that last week. However, the epoxy or resin you typically use for this kind of thing is the most foul-smelling chemical I have ever worked with. Most of them require you to work outside with a respirator on. It’s that bad. So, I would either need to use a resin that is less stinky (and way more expensive!) or …

Is that … is that a garbage can? Ethan, you’ve lost your mind this time.

Yes, that’s a couple of enormous trash cans with bags of fine sand inside. Sand? Trash cans? What kind of crazy plan is this?!

You’ll have to find out later. I’m off to the workshop to finish a sword! Wheeeee!

The Mothermould!

Woohoo! This has been a crazy exciting week. I stubbornly went back for another try at the mother mould for Clariel. I was terrified that I’d fail once again and have wasted over 100 euros on silicone.

I was especially nervous because one spot was a bit of a different colour and firmness than the rest.

But it wasn’t sticky and my finger didn’t sink into it soooo, let’s get it out of the moulding box.

Well it looked like it was all okay. But I would only be able to know for sure by separating the two halves. This was the moment of greatest tension. The moment of truth! Would it be sticky inside? Would it have somehow cured to the other half, trapping the model sword inside?! I didn’t know. I’d have to open it and find out.

It cured! It cured all the way through and didn’t do anything crazy! I can’t tell you the relief I felt. That was so much work to get it right and my mistakes were not cheap but it all paid off.

All cleaned up and ready for a mould jacket!

Ahh, there it is. That’s exactly what I wanted. I really needed that win. it fits together just perfectly. No weird gaps. No bubbles. No cracks. Hurrah!

Now on to the mould jacket! This mould is too wobbly to support itself indepedently so it needs a “cast” around it to keep it from popping open or deforming when I pour the resin in. Imagine it like a body; right now, it needs bones so it can stand up. 🙂

I tried some really gross-smelling plastic stuff.

And it hardened before I was done working with it! well that’s useless.

So I gave my dear mould a nice, relaxing mud-mask.

I thought it looked stressed out. This’ll help.

Really, though, that’s hobby concrete smooshed into layers of burlap cloth. I’m hoping it will be strong enough when dry to not crack or crumble. We’ll have to see! This is how I left it last Friday night so this morning I will check on it and see how my experiment went. Don’t worry! I’m not out of ideas yet!

I have determination! I have sisu! And if that doesn’t work, I have coffee.

Round Two: FIGHT!

I know, I know, I haven’t got any new pictures for you today. Bad Ethan! 😦 I was so busy getting the mould box reconstructed that I forgot to take a photo of it! I’ll make it up to you and take lots of photos of the process today. Forgive me?

I got my order of silicone in at the end of last week and I am ready to have a rematch with the half of the sword mould that cured too fast! Everybody cross your fingers, toes, and eyeballs for me and hopefully we’ll have a brand new mould ready to rock by tomorrow.

Are you excited? I’m terrified! Let’s go! ADVENTURE! 😀

I hate bubbles.

No really. They’re all well and good when you’re blowing them into the air on a sunny summer day, but when they’re in your mould? Sucktastic.

This will not produce a lovely smooth sword. This will produce a mostly lovely smooth sword with weird little warts all over it. Unacceptable.

So why is it like this? What happened? Well, it turns out that my workshop was hotter last week than I thought it was. Zhermack’s beautiful ZA22 silicone’s normal working temperature is 24 degrees Celsius. That means that, at 24 degrees, this lovely blue goo will set in 60 minutes. If it’s colder than that, it will set more slowly giving you a longer working time. But if it’s hotter …

The setting time is dramatically faster! I was in the middle of degassing it when it started turning into a sticky glop the consistency of cookie dough. I knew I was in trouble. 3 litres of silicone is NOT cheap. I pulled it out of the vacuum chamber and poured it as fast as I could. It was sticking to the inside of the container and I had to shove my hand into it (gloved of course) to pull out the rest because it wouldn’t flow anymore. It was like working with a huge mass of chewing gum.

As you might guess, bubbles got trapped in the silicone because it was just too viscous (thick) for the air to escape.

What to do? That right there is about a 108 Euro mistake. Yikes. Well, the important bit is the mould that immediately touches the sword I’m going to be casting. That has to be perfect. The rest of it? Meh. Nobody’s going to see any of that. So I decided to cut out the middle section of the mould and re-pour it instead of re-pouring the entire thing.

I should have re-poured the entire thing.

So what’s this crazy deformed blue crocodile thing? That’s the mould. You might notice a slight gap there in the side.

And by ‘slight gap’ I mean it’s wide enough to see the model sword inside the mould when it’s closed. So if I used the mould like this, all the resin would leak out the side. Why did it do this? Well, you might notice that the left side of the mould there has no gap. Let’s have a top-down view so you can better see what I’m about to explain.

The top half of the mould is where hilt is and also where all those funky vents and the pour spout is. That makes it thicker than the funny banana-shaped bottom half where the blade is. Of course, the thicker bit is heavier. So when I poured the silicone into the middle section that I chopped out, the heavy top half stayed put, but the lighter bottom half floated! Since it only lifted up about a centimetre, I didn’t notice the movement.

The silicone I poured into the middle part to re-mould the sword bonded nicely with the rest of the silicone mould around it. Yay! But the silicone that crept in between the two halves of the mould didn’t stick to either side even though I cleaned one of them really, really well, and sealed the other very thoroughly. It would not obey my wishes and stayed a crazy blue flap just hanging out in between the two halves of the silicone sandwich.

So what do I do? Uhh … well I don’t have enough silicone left to re-pour the half of the mould I messed up. I’m not completely sure my budget can withstand another silicone purchase this month. We’ll have to see. So I’m going to attempt a weird “spacer” where the gap is so I can at least use the mould until I can re-pour the other side. What I’m going to make that out of is still up for debate. Possibly some kind of polymer plastic. Possibly rubber of some kind. Possibly uh … I don’t know. I’m going to experiment with many kinds of goo and see what works.

I have learned a lot from this mistake so it’s not entirely doom and gloom. So I’m trying to look on the bright side. It’s still frustrating for me cause I really wanted to be casting my first sword in the new mould this week. Oh well. The Iron Sisters are stubborn for a reason! Don’t give up!

Stay tuned for more exciting news including a brand new sword I just finished. I’ll give you a hint: it has nothing to do with Shadowhunters!

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