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1. Silikonski kalup i levkoviSilicone rubber mould and funnelsgavamo smolu iz injekcije. Tom prilikom deluje više različitihsila (menjanje ugla prodora igle, pritiskanje ili povlačenjekalupa). Kada punimo kalup epoksiy smolommože da se desi da u strukturi dopune ostane vazduh i dase stvori rupica, koju kasnije moramo da napunimo.Mehurići i skupljanje smolePrilikom ulivanja smole u kalup u mrtve uglove uđei nešto vazduha. Mehuriće možemo uneti u kalup i slabominjekcijom. Ti mehurići su po pravilu vrlo mali i ugustoj epoksi smoli ostaju na dnu. Veći mehurići lakšeisplivaju na vrh, osim u primeru tankih odlivaka, kadapovršinski pritisak između unutrašnjeg i spoljašnjegkalupa zadrži mehuriće na mestu. Mehurići mogu da sepojave i nešto kasnije, kad smo već uspešno napunili kalup.Ti mehurići predstavljaju vazduh koji se skuplja namestu gde je kalup zalepljen na staklo, što se može desitii 15 minuta nakon punjenja kalupa. Sve do početkareakcije stvrdnjavanja smole, mehurići se mogu pomerati.Kasnije ih je nemoguće odstraniti i zbog toga moramoponovno da napunimo te novonastale rupice.Epoksiy smole se u proseku skupljaju 2%. Potrebno jeobezbediti dodatnu količinu smole, a to postižemo viškommase u levkovima.KalupRazmišljanje o svim tim problemima dovelo nas jedo spoznaje da se do grešaka dolazi upravo u procesu2. Spoljašnji i unutrašni kalupInner and outer mouldled. This is particularly true if resin is injected into a mouldusing a syringe. These bubbles are usually very smalland do not rise in dense epoxy resin. Larger bubbles risemore easily, except when the cast is thin and the surfacepressure of the inner and outer mould keeps the bubble inplace. In addition, air bubbles may become trapped by anglesin the edges of the glass. Air bubbles can also appearwhen the mould has already been successfully filled up.The air floats out of the space where the mould is fixed toglass and this may happen even 15 minutes after the mouldhas been filled. The bubbles can move until resin beginsto cure, after which it is impossible to get rid of them,so that new resin has to be used to file the holes left in thecast. If this is not done before the first resin has cured fully,the join between the two batches of resin will be visible.On curing, epoxy resins shrink by an average of 2%, sothat it is necessary to compensate for this by leaving asmall excess of resin in the funnel.Making mouldsReflecting on all these problems, I concluded thatmany mistakes were made during the process of making3. Pričvršćivanje silikonskog kalupa uunutrašnost predmetaFixing of a silicone rubber mould to theinner wall of the glass1564. Vidljiva su mesta gde kalup nije najboljezalepljen uz staklo. Na tom mestu će seepoxy smola preliti preko originala.The areas where the mould is insufficientlysecured to glass are clearly visible. Hereepoxy resin will flow over glass.Silikon kaučuk kojim smo lepili kalup nastaklo je iscurio u unutrašnost kalupaSilicone resin used to secure the mould toglass has flowed into the mould.