Winter Wreaks Wild (wip): UD 2/11 Further Adventures of the Caping Crusader

[Alfrik]

Capes add a nice touch.

[Silent Invader]

Thanks chaps

The experiment is to see if I can make cloaks from injected thermoplastic ('hot glue') having moulded the master using an instant grab adhesive.

I've tested the hot glue against the cured adhesive and it seems to work but the true test is with a cloak.  Considerations include detail and longevity, though the latter is unclear to me at the mo.  Thickness adds stiffness, thus the thicker profile than for my other method.

I've gone for a fairly simple but billowing cloak shape that - as Rui said - can be modded and varied with greenstuff.  

Just to clarify, this is primarily for plastics, as using the paper and superglue technique on them seems to be a bit more of a hassle than with metal.

Btw the new faction will have longbows (obviously) and probably represent a neighbouring country.

[warlord frod]

Hot Glue........Hmmmmm. I will be interested to see how well that works.

[Silent Invader]

I didn't make it clear that only the superglued paper is in contact with the plastic dolly. The greenstuff does not touch the plastic, which makes the cloak really easy to pinch, wiggle and peel away from the dolly, as the superglue join between plastic and paper is very brittle.

The cloak is removed:







Next step is to tidy up the cloak to finish and prep it for moulding.  In the meantime, here's the master in what will be the mould box.



The box is made from ABS plastic, which is quite inflexible, easy to drill and reasonably cheap (aside from the glue gun, from Maplin at £3.09 the 'project box' is the most expensive part of this experiment).  As the hot glue will be pressure injected, logic suggests that a totally inflexible box would be better but steel or thick-ish aluminium would be less easy to drill and more expensive (if I could find such a box this small!).

Hopefully I'll be able to finish the greenstuff work today and make the first half of the mould tomorrow.

[OSHIROmodels]

Ingenious mate 

Really hope it works 

cheers

James

[rumacara]

Hhuuuummmm!!!

Giving me some ideas.
Keep it coming Steve.

[Silent Invader]

Thanks chaps ..... It's an experiment so it might all go wrong but here's the next steps:

Cleaned up the master of the cloak, which mostly entailed smoothing the inside surface by scraping with a scalpel then adding greenstuff:



I took the lid of the mould box and drilled 1mm dia holes:



I then brushed the master with Vaseline (taking care to avoid lumps and infill of detail) before setting it inside the mould box in a bed of plasticine; after positioning, both the master, plasticine and exposed sides of the mould box then had a careful brush of Vaseline:



Using a brush I then dabbed a No More Nail type adhesive (I used B&Q Instant Grab Adhesive) onto the master:



I then mixed a quantity of the adhesive with pure baby talc (@ 50% by volume) and overfilled the remainder of the cavity in the mould box; the box screws had been given a brush of Vaseline and were inserted into their threads to prevent ingress of the moulding material:

(NB: the talc was added to try and add strength to the adhesive by lowering its brittleness while hopefully speeding curing time: it might work, it might not!)



With the screws removed and the snapped ends of a broken cocktail stick inserted into the screw holes, the lid was eased into position and - taking care not to block the escape holes - was pushed shut:



The cocktail sticks were then removed and the screws reinserted and tightened closed (though I did also press down onto the two corners without screws to ensure alignment - a screw in each corner would obviously be better):



The worm-like extrusions are of course the excess mould material being forced out - I haven't wiped it off as it will give some indication that curing is taking place.  Based on recent DIY experience using the adhesive as a gsp filler, I'm reckoning 2 days on it curing though given that it is almost a sealed container there's the risk it might not, though the numerous escape holes should help.

Btw as I had some greenstuff to spare I started on some dead dog markers, which are the dog minis clipped from their bases then reshaped with clippers and pliers - missing paws won't be an issue as snow will cover where necessary (but still wip):



The dogs are mostly from miniatureMOJO (store to reopen soon!) though there are also a couple from Conquest Miniatures that I don't think are retailed anymore:



More soon 

[Mason]

Very interesting to see your moulding process for the cloaks.
It reminds of those Play-Doh things that were around when I was a kid with all those 'worms' popping out of it.
 

[Doug ex-em4]

That moulding process was fascinating - can't wait to see the result. As someone who makes moulds the easy way (rubber discs and vulcaniser) seeing this kind of improvisation and innovation makers me full of admiration.

Bated-breath time until that mould is opened...

Doug

[Silent Invader]

And...... It didn't work ...,. Yes I know I opened it earlier than I said I would but I'm an impatient bugger  

But all is not lost.  I washed off the mould material (it was a long way from curing) and reapplied petroleum jelly to the interior of the mould box, master and plasticine, and also to the rim of the lid and the screw threads/holes.



I think I've said before that I hate using resin.  Well my contingency is cheap and cheerful resin in the form of pound shop epoxy:



Compared to the instant grab adhesive, the downsides are fumes, working time, bubbles introduced while mixing, and a question mark over whether it will cope with the heat (it's rated to only 93*C). The compelling upside is that unlike the grab adhesive it will cure in an enclosed space!  

Adherence to the H&S advice is a must.



So I mixed the resin and hardener, pouring it alongside then over the mould, dabbing it into crevices and pricking bubbles with a cocktail stick; it turns white as if cures and so I very quickly replaced the screws with the thick ends of a broken cocktail stick, pressed the lid into place to squeeze out excess, then screwed it closed (pressing down on the two screwless corners).

It turns after about 5 mins and has full strength after an hour .... Not long to wait now  

[OSHIROmodels]

Top marks for ingenious innovation mate but......

Just buy some RTV silicon and resin 

cheers

James

[Silent Invader]

So little faith.... One doesn't quit so early in the game! 

Btw I did consider rubber for the mould but whether RTV or vulcanised it's likely to move under the pressure of injection, which means I'd have to cast in resin, which I really don't like using.

Anyways, some success!

I prised apart the mould box using craft knife and fine-bladed screwdriver:



And cleaned up using sculpting tool, cocktail stick, paintbrush, detergent and warm water, ready for the next step, making the other side of the mould:



Incidentally there are a few undercuts but as the cured thermoplastic has a little bit of flex it should be fine.

[Mason]

Bloody clever and persistent.
 

It is a good thing for the rest of us that you are not mega-rich.
I have visions of all kinds of mad experiments going on.
Silent Invader AKA Dr Boris Balaclava, Bond Villain and Criminal Mastermind.
 

[Doug ex-em4]

It is a good thing for the rest of us that you are not mega-rich.

I'm pretty sure I heard somewhere that in fact he is - but also very eccentric...

Doug

[Silent Invader]

 

Well for the next stage I was wearing gloves, goggles and respirator ..... All that was missing was the balaclava

 

All of which were needed as what happened was quite, er, interesting!

Incidentally, as I had with the top, I drilled 1mm dia holes in the bottom of the mould box to allow the escape of excess resin. Everything except the inside of the bottom part of the box had a brush of petroleum jelly.

So, for the top half I used the pair of tubes at 10ml each but for the bottom, with a bigger cavity to fill, I doubled up.

I mixed a pair of tubes and dabbed some over the master that was embedded into the top half, using a cocktail stick as before to ensure complete coverage.  The remainder was poured into the bottom half, which was sat on a couple of sheets of paper (remember, there are holes in it) with cocktail sticks blocking the screw holes.  Bearing in mind the 5 min cure time I very quickly mixed the second pair of tubes, popped on the top, whipped out the cocktail sticks and screwed it shut. I closed the mould off of the table and so the excess started to ooze out of the vents in the base.

When this resin starts to cure it gets hot and the doubled up quantity seemed to get hotter: it might have been an optical illusion but the bottom of the ABS box seemed to swell with the heat and for a moment I thought it might explode.  Maybe the 'swelling' was really just the excess resin oozing out, or maybe it really was heat expansion having its effect.  



In about an hour I shall attempt to open the box.........