Trial with Canvas painted with Gesso and some acrylic paint. Brown spots just paint marks.
- Wiped canvas with isopropyl alcohol cloth to remove oily fingerprints.
- Mixed MasterCast 121 (200ml) for 4 minutes, left to stand for 1 minute
- Poured in zig-zag pattern on canvas (both sides)
- Spread with spatula to edges
- Needed to push resin to edges, especially side with tape barrier
- Normal edge: When resin retracted a bit on edge, added a bit more from my resin stirrer.
- At 30min resin still fluid (working in hot room)
- Normal edge:At one point the resin found a hollow edge to start spreading down. Once that starts more resin wants to flow in the drip path. Used wooden stirrer to scrape the edge and resin then pushed to top again. Did this several times.
- Flamed surface and edges to pop bubbles.
- At around 40min resin was still fluid, but more viscous, and added thin line of resin on one edge to test. Works well, but cons are: (1) getting a bit late to flame to get rid of bubbles, as flaming when setting can cause dents , and (2) have to be careful not to mess resin on blank edges. Pouring thun stream worked.
- When resin fairly set (around 50 min) can still scrape spilled edge and although it initially looked rough where scraped it still smoothed, but stopped spilling over.
Where resin spilled over, obviously side a bit more shiny.
Barrier method may not work for you, as cons are:
- Extra time to paste blue tape on edge and smooth
- Tape seems to stick to painted canvas when edge rubbed with wooden spatula to ensure resin does not flow between canvas and tape. More difficult to pull off, but reminant tape can be rubbed off.
- The canvas edge is round, so resin fills this edge and makes a ridge against the barrier.
This ridge can be removed with a sharp blade when resin is cured (but still soft – did mine at ~17 hrs, but should be sooner) OR using a small angle plane, giving it a nice finish – can’t go too close to canvas.
Generally very time-consuming as one has to watch the resin harden to a point where it no longer spills over or fix small spots where resin not enough.
Some area did make small hollows – suspect invisible “oily” spots (fingerprints?) on canvas, but just filled with drips of resin and they went away.
Resin thickness on canvass measured was 0.77mm.