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  • #173139
    OotKust
    Participant

    Well, just modifying actually.

    Anyone tell me the chemical effects of using AC and Milliput Superfine White™ (as a filler/ bonding component).

    I have to take a figure, change parts, like arms, heads etc. to create a new and ‘correct’ uniform sometimes. I use the pin and glue technique to re-attach the small parts, lets say a head and hat. I use steel sewing pins suitably trimmed, but I have also been using the old ‘lost’ staples of paper days- those flat surfaces seem to give a better hold- all neatly fitting into a drilled hole in both components.

    In the case of ‘decapitation’, it often (meaning always) happens that the surface isn’t flush, so some filler milliput is required, either within the join, or along the outer edge, to reset the collar/ hairline area to a paintable surface.

    Now it may be just an aged pack of milliput, but I’ve noticed that it takes much longer to ‘set’ the mixture.

    Being an impatient type I like to motor on these mods and expect them to be ‘dry’ and set in 24 hours. Sometimes now it takes 4-5 days.

    Any technicians/ chemists thoughts/ observations?

    cheers -d

    Blinking paint by numbers... bahhumbug!

    #173158
    Mike
    Keymaster

    That sounds off.

    For quick emergency fills I use plasticine and superglue.
    Not great but works.
    Otherwise I use greenstuff.

    #173169
    vexillia
    Participant

    OK I’ll bite.

    Dealing with just Milliput:

    [1] Milliput is a two part epoxy. The first is a monomer which hardens when a polymerisation reaction is initiated. The second part is an initiator for the first part (how very Marx Brothers).

    [2] The initiator is not stable indefinitely. It has to have a certain “reactivity” (non-technical term) to act as an initiator.

    [3] As the Milliput ages so will the initiator decrease in potency. It will, however, not degrade to the point of not working at all for quite some time (years?).

    [4] A weaker (older) initiator will produce a slower reaction with the monomer when mixed. Thus older Milliput will harden (or set) far more slowly than fresh.

    Hope that helps?

    If you tell me what AC is I might be able to help further.

    Martin Stephenson :: Work | Blog | Auctions

    #173185
    Steve Johnson
    Participant

    With Milliput and Greenstuff, you need to mix a relatively large amount to make sure you get a good mix of the component parts, to allow the chemical reaction to take place properly. Too small amounts and it doesn’t work as well, so may not go off properly, not be strong enough etc.

    #173186
    OotKust
    Participant

    Thanks,

    will get back to you tomorrow. I possibly meant CA !

    Blinking paint by numbers... bahhumbug!

    #173189
    Paint it Pink
    Participant

    An addition to the Milliput: warmth will speed drying time; likewise cold will delay it.

    Also, in this case add more of the activator to the mix (the one that develops the crust).

    PS: mixing greenstuff (Kneadite) to Milliput will allow one to combine the attributes of both, which is sometime useful.

    PPS: CA can irritate, and in extreme cases people have been known to develop an allergy to the product. It is very quick to set though, but don’t mix it with Milliput.

    One is good, more is better
    http://panther6actual.blogspot.co.uk/
    http://ashleyrpollard.blogspot.co.uk/

    #173192
    Guy Farrish
    Participant

    Okay I don’t mind being dumb – CA?

    The only thing I can think of, sort of in context, is cyanoacrylate but why, or more importantly how you might mix that with Milliput defeats my puny brain.

    I’m missing something aren’t I?

    #173195
    Thomaston
    Participant

    @Guy
    I thin he’s using CA to glue the pinned parts before filling the gap with miliput adn wondering if they react rather than mising the two together.

    My own experience I’ve had good results with superglue on fresh greenstuff to squickly harden it (the surface at last) and its easier to file smooth.

    Ther’s also that CA + baking soda trick but its much less controllable.

    Tired is enough.
    I like tiny miniatures

    #173200

    While discussing the chemistry of milliput and CA, i have also been wondering about another chemistry type question about what sort of resin is best (cheapest) for making figs from molds (both silicon and latex). I have just started sculpting some masters in Acer’s epoxy and want to eventually try some duplicates.  I saw a huge lot of cheap acrylic powder and wondered if it could be used.

    Mick

    #173201
    Guy Farrish
    Participant

    Thanks Thomaston.

     

    (PS – Thomaston/Mike/anyone, that @Guy leads me to another Guy – Barlow, who, unless I am leading a very convincing double life, ain’t me – any idea how this happened?)

    #173207
    willz
    Participant

    I drill and pin, stick with super glue, fill small gaps with liquid green and larger gaps plasticine or blue tac covered in super glue or two part epoxy resin glue.   Drying times for glues, fillers, paints, varnishes and the like are all dependent on whether it is cold or hot.  As to chemistry it isn’t worth bothering about, don’t sweat the small stuff.  This a hobby for fun and enjoyment,

    #173212
    OotKust
    Participant

    I thin he’s using CA to glue the pinned parts before filling the gap with miliput adn wondering if they react rather than mising the two together. My own experience I’ve had good results with superglue on fresh greenstuff to squickly harden it (the surface at last) and its easier to file smooth.

    Ok then, yes you’ve covered most bases.

    Well I used AC- because we/they used to call it ‘AlphaCyana..’ 30-40 years ago when it became available. Then ‘they’ dropped the Alpha bit but my brain still hangs there… sometimes.

    I do not intentionally mix the two as you surmised. Yes without pins, small parts are at risk in day to day handling. Having repaired many and lost a few in multi-person games, I now build to the ‘norm’.

    As to chemistry it isn’t worth bothering about, don’t sweat the small stuff. This a hobby for fun and enjoyment,

    I wasn’t after a ‘pure’ chemical analysis anyway-  I had become aware of the hardening effect on a segment of the M’put™ in previous conversions, so wondered if anyone would expand on that. I do not intend to use it as a ‘hardener’ per se, but interesting that it works.

    Yes I’m aware of setting atmosphere variables; normally I’d be doing this on warm airy days, but we are in Autumn here. Yes I’ve used [Edit**  the curing process of ** ] the oven set to 100ºC and then placed on aluminium cardboard bond tray. No more than 15 minutes and job done. Even partly painted/ primed  can survive.

    I used to distribute M’put in NZ so have been using it almost as long as modelling; Greenstuff isn’t freely available here and frankly I’m not interested in re-learning my tools. And yes, the box/ tubes of M’put© are hardening and old, so I must selectively ‘trim’ the core to get the most miscible part.

    Thanks for the info, appreciate the backup and new stuff too!

    d

    Blinking paint by numbers... bahhumbug!

    #173213
    kyoteblue
    Participant

    Very useful info, thanks yall.

    #173232
    Mike
    Keymaster

    Thanks Thomaston. (PS – Thomaston/Mike/anyone, that @Guy leads me to another Guy – Barlow, who, unless I am leading a very convincing double life, ain’t me – any idea how this happened?)

    Your username is not guy…  nor has it guy in it.

    https://www.thewargameswebsite.com/forums/users/gwydion/

    😀

    #173248
    Guy Farrish
    Participant

    Ah! So it was just Thomaston using the shorthand @ sign + my name that accidentally created the link to another Guy.

    Thanks. :^)

     

    #173277
    Mike
    Keymaster

    Yup.

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