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  • Guest

    #1

    Differences in kits

    With me being new to modelling can I ask what is the difference between plastic and resin kits and figures.
  • Guest

    #2
    The material and production methods

    Plastic kits are made from plastic pellets that are heated and then squirted at high pressure into metal moulds to make the sprues with the parts. This requires an expensive machine and expensive moulds, but is cheap in raw materials and labour, meaning that large runs give you low cost per kit.

    Resin kits are made by mixing a two-part synthetic resin, which results in a liquid that will set hard over time. While it’s liquid, it is poured into a rubber mould, and removed once it’s hardened. The moulds are relatively cheap, but it involves a lot of labour to make both the parts and the moulds, because those wear out quickly, and waiting time for the resin to harden. This makes them more expensive per kit for big production runs, but cheaper if you’re only going to make a few hundred or thousand kits.

    The difference in materials means they need entirely different techniques, really. You can’t even use the glue for plastic kits on resin, because it won’t stick parts together This because these glues dissolve the plastic so the parts get welded together when the glue evaporates again, but resin doesn’t dissolve in it, so you need superglue, epoxy glue, etc. for it.

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    • Guest

      #3
      Thank you Jakko for the information most helpful. The reason why I ask is because my wife has bought me a 1/35 MIG Russian tanker figure in resin.

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      • Guest

        #4
        If you look at the parts, you’ll see it has only a few, with undercuts and things that you don’t get with plastic parts. This is because the rubber moulds allow more complicated shapes to be cast than in metal moulds.

        It also means you often have to remove larger excess bits, so-called pouring plugs, by cutting or sawing them off. Be careful with this, because resin is fairly brittle. It cuts and carves well (like soft, grainless wood, it’s sometimes said) but can also break like glass or pottery. You also don’t want to be breathing in the dust from sawing, filing or sanding it, but slivers cut or scraped from it are not dangerous.

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        • KarlW
          • Jul 2020
          • 1522

          #5
          Resin can give better definiton than plastic, needs a slightly different approach to assembly, but once the primer is on the paint does the same job.
          As Jakko has mentioned sawing the plugs off if the biggest step, a razor saw is really hard to beat for that job, but you can carve them away with care.

          Comment

          • Guest

            #6
            Just remember you need CA for gluing Kevin.
            Maybe a slow type to get parts completely lined up.

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            • Steve-the-Duck
              SMF Supporters
              • Jul 2020
              • 1731
              • Chris
              • Medway Towns

              #7
              Also with resin, wash the parts before construction - I know that goes for plastic too, to remove mould release agents
              Be aware of how the parts go together as the plugs are often attached to mating surfaces

              Comment

              • Dave Ward
                • Apr 2018
                • 10549

                #8
                Kevin,
                If you're sawng resin, take care, the dust is unpleasant stuff, you should wear a proper mask.
                Dave

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                • Guest

                  #9
                  Originally posted by KarlW
                  sawing the plugs off if the biggest step, a razor saw is really hard to beat for that job, but you can carve them away with care.
                  I prefer to use a knife for all but large plugs. If it’s no more than a couple of millimetres thick, you can use a knife to keep scoring the area where the plug attaches to the part until you either get through or go far enough that you can snap the plug off. (Only do that with thick parts, though — try to snap the plug off a thin part and it’s likely the part will break instead or as well.) After that you can clean these parts up by scraping with a knife. All of this avoids creating dust, which is bad for your lungs.

                  Comment

                  • Ian M
                    Administrator
                    • Dec 2008
                    • 18272
                    • Ian
                    • Falster, Denmark

                    #10
                    A good alternative when sawing or sanding resin is to put a wet cloth on the worktop as it catches the dust and stops it blowing everywhere.
                    Group builds

                    Bismarck

                    Comment

                    • KarlW
                      • Jul 2020
                      • 1522

                      #11
                      Originally posted by Steve-the-Duck
                      Also with resin, wash the parts before construction - I know that goes for plastic too, to remove mould release agents
                      Be aware of how the parts go together as the plugs are often attached to mating surfaces
                      Modern hard styrene kits don't use mould release.........the old soft type of plastic did and needed washing and the habit just stuck.
                      Click image for larger version

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                      • Steve-the-Duck
                        SMF Supporters
                        • Jul 2020
                        • 1731
                        • Chris
                        • Medway Towns

                        #12
                        Indeed
                        I always scrub the greasy paw marks off my slabs of resin armour - Just to make sure! Sometimes before AND after

                        Maybe it's from the time half the paint came off an Airfix multipose figure I was finishing...

                        Comment

                        • Guest

                          #13
                          Originally posted by KarlW
                          [ATTACH=CONFIG]n1129028[/ATTACH]
                          Much better than the movie …

                          Comment

                          • KarlW
                            • Jul 2020
                            • 1522

                            #14
                            Originally posted by Jakko
                            Much better than the movie …
                            I enjoyed the new films as I expected a new "Phantom menace".........

                            Comment

                            • Guest

                              #15
                              Let’s just say I skipped Solo and whatever Episode IX is called …

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