Bob the Alien (Giger inspired Alien)
- Thread starter Leigh
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Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
Awesome, Leigh. As Matt said, you do get bubbles with thixo. Experiment with how much to use a bit, first...the less thixotropic you make it, the easier it is to avoid bubbles (and the more silicone slumps off the model, to be wasted).
Awesome, Leigh. As Matt said, you do get bubbles with thixo. Experiment with how much to use a bit, first...the less thixotropic you make it, the easier it is to avoid bubbles (and the more silicone slumps off the model, to be wasted).
Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
I'm planning to do 2-3 runny coats first & once I have a fairly good coat I'm planning to use the thixo to fill the deep area's & bulk up the overall thickness with runny coats in between thixo coats. I'm going to have to be meticulous with bubble removal, the convoluted tubes that run over his head are major bubble traps. I'm aiming for a minimum silicone thickness of about 10mm/ 3/8" before I start on the jacket
I'm planning to do 2-3 runny coats first & once I have a fairly good coat I'm planning to use the thixo to fill the deep area's & bulk up the overall thickness with runny coats in between thixo coats. I'm going to have to be meticulous with bubble removal, the convoluted tubes that run over his head are major bubble traps. I'm aiming for a minimum silicone thickness of about 10mm/ 3/8" before I start on the jacket
Too Much Garlic
Master Member
Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
I can't recall whether you mentioned if you had done molding before or whether anyone has suggested this previously, but whatever you do: test the molding technique on an unrelated complexly shaped item first, so that you get the hang of it before starting the daunting task of molding this beast.
I can't recall whether you mentioned if you had done molding before or whether anyone has suggested this previously, but whatever you do: test the molding technique on an unrelated complexly shaped item first, so that you get the hang of it before starting the daunting task of molding this beast.
Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
Daunting... that's an understatement!!
It's Started...
I didn't realise just how much work there is in producing proper moulds, its almost as much work as the sculpting!
Anyway I've started it, I don't know whether I'm doing it right but it's started.
I struggled yesterday with the clay & getting the shape into something that I think will work. I have the Flu & I usually get a numb brain when I've got the Flu. Trying to picture the reverse of the part I was building was a chore! I really struggled with it but I think it'll work, Just having trouble engaging my brain at the moment :$
I decided to start the moulding process with a part I'm familiar with & it has no soft area's so should present less chance of failure... in theory
I added some sprue to the tips of the teeth & a couple of other area's in an effort to reduce any air traps in the castings. The theory being that any air present can be trapped in the holes left by the sprue & not in an important part of the cast. Any remaining sprue left on the cast can be trimmed off To hopefully leave a clean relatively bubble free casting.
Here's the rubber, not the prettiest but hopefully it'll work.
It's been about 12 hours now since the last coat of rubber & I'm hoping to make up the jacket for this half of the mould this afternoon. I'm using fiberglass & polyester resin for the jacket.
Daunting... that's an understatement!!
It's Started...
I didn't realise just how much work there is in producing proper moulds, its almost as much work as the sculpting!
Anyway I've started it, I don't know whether I'm doing it right but it's started.
I struggled yesterday with the clay & getting the shape into something that I think will work. I have the Flu & I usually get a numb brain when I've got the Flu. Trying to picture the reverse of the part I was building was a chore! I really struggled with it but I think it'll work, Just having trouble engaging my brain at the moment :$
I decided to start the moulding process with a part I'm familiar with & it has no soft area's so should present less chance of failure... in theory
I added some sprue to the tips of the teeth & a couple of other area's in an effort to reduce any air traps in the castings. The theory being that any air present can be trapped in the holes left by the sprue & not in an important part of the cast. Any remaining sprue left on the cast can be trimmed off To hopefully leave a clean relatively bubble free casting.
Here's the rubber, not the prettiest but hopefully it'll work.
It's been about 12 hours now since the last coat of rubber & I'm hoping to make up the jacket for this half of the mould this afternoon. I'm using fiberglass & polyester resin for the jacket.
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Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
!!!!!!!!!
Leigh as usual your 'newbie' makes other people's 'pro' look sub-par, old son. :lol Nice claying up there. Yes it is a bugger of a job - it's an actual sculpting job itself.
I'm not sure about the blanked-off sprues, an air bubble is an air bubble unless you're going to put a fair weight of resin onto it. Not seen that done before, I'll be interested to see if it works (and stealing the idea).
OTOH is it necessary to pour this one with the teeth facing upwards? If it can be avoided I'd probably want to pour with them oriented downwards.
!!!!!!!!!
Leigh as usual your 'newbie' makes other people's 'pro' look sub-par, old son. :lol Nice claying up there. Yes it is a bugger of a job - it's an actual sculpting job itself.
I'm not sure about the blanked-off sprues, an air bubble is an air bubble unless you're going to put a fair weight of resin onto it. Not seen that done before, I'll be interested to see if it works (and stealing the idea).
OTOH is it necessary to pour this one with the teeth facing upwards? If it can be avoided I'd probably want to pour with them oriented downwards.
Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
Thanks
I'm going to Slush Cast the jaw. I'll pour enough plastic in there to make the thinner areas solid but there'll be a void in the middle so that its not one solid lump.
I could just imagine the cast coming out with bubbles at the tips of the teeth. Since the teeth are a major feature I want them to come out crisp & bubble free, so I figured by adding a little void in the mould at the tips of the teeth, the void will hopefully catch any bubbles just leaving a little extra plastic at the tips to trim off
Thanks
I'm going to Slush Cast the jaw. I'll pour enough plastic in there to make the thinner areas solid but there'll be a void in the middle so that its not one solid lump.
I could just imagine the cast coming out with bubbles at the tips of the teeth. Since the teeth are a major feature I want them to come out crisp & bubble free, so I figured by adding a little void in the mould at the tips of the teeth, the void will hopefully catch any bubbles just leaving a little extra plastic at the tips to trim off
Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
The time, stress, and thought that goes into mold making surprised me The time, stress, and thought that goes into mold making surprised me as well. Good job so far!as well.
Good job so far!
The time, stress, and thought that goes into mold making surprised me The time, stress, and thought that goes into mold making surprised me as well. Good job so far!as well.
Good job so far!
Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
Thanks
I'm guessing as I do more & get used to what I'm doing I'll find it easier. But yeh I'm finding it quite alot of work at the moment.
It could just be that I'm not feeling very well that's making it seem harder :confused
Anyhoo, I've been making up the jacket for this half this morning, GRP jacket, in my Dinning room Damn does it Pong!
The missus will have a fit when she gets home :eek
I'll post some pic's up in a bit
Thanks
I'm guessing as I do more & get used to what I'm doing I'll find it easier. But yeh I'm finding it quite alot of work at the moment.
It could just be that I'm not feeling very well that's making it seem harder :confused
Anyhoo, I've been making up the jacket for this half this morning, GRP jacket, in my Dinning room
Damn does it Pong! The missus will have a fit when she gets home :eek
I'll post some pic's up in a bit
Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
:lol She's a star! She'll be alright
Here's those pic's:
I made up some shapes in clay to lay the FG up over, it should give me a good edge to build up the other half on to so that they lock together.
I'll have to trim the very edge of the FG to tidy it up a bit
:lol She's a star! She'll be alright
Here's those pic's:
I made up some shapes in clay to lay the FG up over, it should give me a good edge to build up the other half on to so that they lock together.
I'll have to trim the very edge of the FG to tidy it up a bit
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Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
Leigh, as always perfection!
I've always found mould making to be a hugely time consuming occupation, but if done well (as we always see here) the benefits of usability and casting quality are enormous.
I just hope that when you've finally finished this beautifully complex project that you choose something simpler to build next time, such as a full size Nostromo - you know something with lots of flat pieces and not so many undercuts!!
I can’t wait for the next installment.
Leigh, as always perfection!
I've always found mould making to be a hugely time consuming occupation, but if done well (as we always see here) the benefits of usability and casting quality are enormous.
I just hope that when you've finally finished this beautifully complex project that you choose something simpler to build next time, such as a full size Nostromo - you know something with lots of flat pieces and not so many undercuts!!
I can’t wait for the next installment.
Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
One step ahead of you there mate Its in the garden at the moment finishing off curing & the house is now pong free
Thanks
One step ahead of you there mate
Its in the garden at the moment finishing off curing & the house is now pong free Thanks
Alaneye
Sr Member
Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
I'm a little bit puzzled by what I'm seeing. Are you making all of this upper part of the lower jaw in a single part silicone mould, with a single part FG mother mould? If I'm seeing it correctly, with the ripples in the silicone and the hard master inside that, and the narrow nature of the casting, isn't it going to make it very difficult to get the mother mould off? Where the jaw hinges, aren't you going to get a mould lock because of how they lean outward?
I'm a little bit puzzled by what I'm seeing. Are you making all of this upper part of the lower jaw in a single part silicone mould, with a single part FG mother mould? If I'm seeing it correctly, with the ripples in the silicone and the hard master inside that, and the narrow nature of the casting, isn't it going to make it very difficult to get the mother mould off? Where the jaw hinges, aren't you going to get a mould lock because of how they lean outward?
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Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
It is something I had considered Alan, I knew it would be tight & it is fairly snug but it does come apart
As you can see from the pic's I needed to give myself the ability to push it out rather than pull it out:
It is something I had considered Alan, I knew it would be tight & it is fairly snug but it does come apart
As you can see from the pic's I needed to give myself the ability to push it out rather than pull it out:
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Re: Bob the Alien (Giger inspired Alien) Sculpting finished page 45
I got water clear polyester, I know I could have used a slightly cheaper resin but I thought it would be useful with other things
I got water clear polyester, I know I could have used a slightly cheaper resin but I thought it would be useful with other things
