used to draw on paperboard coaster for commissions. after sketching and coloring, i simply sprayed on them using acrylic. the effect was good;- the colors were enhanced and they looked shiny.
however, if you want to use them drink coasters (as the original purpose serves), you can't put hot drinks on them as it will make their surface tacky.
yet i love the coarse surface, it's perfect for cross hatching. there's no problem if it's used as just another art piece, but having a good sealant on the surface would be great as well.
i did find epoxy at art shops, but it's too expensive: rm 60 for a small can. the finishing is just like another epoxy sticker, not hard enough and could be tacky sometimes. it was then that my friend introduced a 2:1 hard epoxy they've been using in their engineering projects. i tried using below drawing, just a piece of sketching paper glued to polystyrene.
the mixture needs to be poured onto the surface and left for one day to dry. there're problems here and there: air bubbles, spillage, a bit yellowish, and stuff, but the outcome was awesome~
the surface becomes hard plastic! knock it, throw it, it won't break.
basically this method has been used worldwide to seal the surface of paintings and furniture, but to find a good and affordable sealant would be a problem; especially here. i went to plenty of DIY and hardware shops to find the materials yet couldn't find them. of course, there's a lot on ebay, but the prices are not worth it.
while still looking for sealants (a lot of requests on them, i've finished the drawings but they have to work as drink coasters first!), i made some tiles coasters instead. they're easier as i used decorative papers as the pattern. could not use original arts on this as the glue would smear the watercolors.
..and some glass magnets, also using decorative papers..
..and finished some commissions..
it's cheating, but my friend says it's ok. she likes it anyway :p
i've made another blog sharing the *completed* crafts i made. there won't be much posts though, since i would not put stuff i haven't found solution for. hope u guys do drop by sometimes! :)