Updated: Sep 1, 2022
In this (1st of 3) experiments blog post, I'm sharing my experience (rookie errors included), using 3 brand new silicone moulds, and 3 different resins (or combos of) for each of these moulds. I say rookie errors lightly, since I've been using other types of epoxy resins steady for well over 5 years now, but it was my first time I have used these 3" deep larger moulds, and worked with such large floral castings, using these types of epoxy. I started all 3 moulds on the same day, and journaled my experiment process with photos, for those it might be helpful to.
In the smallest mould (6x6x3"), I used iCoat CE4100 HV (1:1 ratio) casting epoxy, 6 layers. This smallest size mould is covered in this blog post (below).
In the middle sz mould (8x8x3"), I used iCoat CE4100 HV (1:1) ratio casting epoxy, for the base layer to set the florals first, then I used the iCoat TP21 (2:1 ratio) casting resin in the following 3 layers. This mould resin combo are covered in a different blog post (part 2 of 3) link.
In the largest mould (10x10x3"), I used iCoat CE4100 HV for base layer to set the florals first, then I used the iCoat Depth (2:1 ratio) deep pour casting resin in the following 2 layers. This mould resin combo are covered in a different blog post (part 3 of 3) link .
Important Note: If you are new to floral preservation casting using epoxy resin, this is NOT a beginner level project. It is important to learn more about, and experience some of the basics with resins, as well as with florals before attempting to cast one of these large floral blocks. Creating with florals in epoxy, has a few different challenges, then just using colourants in epoxy. Please click this blog link called, "Floral Preservation Casting (& Silica Gel tips) for Beginners", and plan to practice on some smaller items first.
6"x6"x3” square block style silicone mould. This size mould holds roughly 60oz / 1.7 liters of epoxy resin total. Amount & thickness of florals organics may effect the volume slightly (so you may want to have back up moulds ready to use for any extra epoxy).
This floral preservation block piece was completed using 6 layers of iCoat CE4100HV epoxy, from ArtWorks Resin Canada.
To see information about using the iCoat CE4100 HV (1:1 casting epoxy), click this blog link called, "Floral Preservation Art Tips using various iCoat Epoxy Resins", and scroll down to section about the version of iCoat resin you will be using.
Smallest of the 3 moulds, 6"h x 6"w x 3"d
Day 1, (Sunday around 12:30pm), first layer, iCoat CE4100HV (1:1 casting epoxy), used roughly 8oz (but could have gone with 10).
With iCoat CE4100HV, you will need to warm up BOTH bottles (bottle of part a & bottle of part b), in a bucket of hot water. I made sure my studio room was specifically warmed up for working with floral casting. Also I used the infrared thermometer gun to check resin temperature inside bottles. Never assume that warm room means warm resin (resin is usually cooler in bottles). Take the lid off, & aim IR temp gun down the neck of the bottle, to get temperature reading of the resin. With this particular (iCoat medium viscosity) resin, once it reaches 82F, you can mix Part A & B together. (With the other iCoat casting epoxies, TP21 & Depth, you would not pre-heat them). Dry off all water from bottles thoroughly. Any water drips will ruin your cure. If needing to warm resin, using hot water in a bucket will heat your bottles up faster then any type of heat or seed mat.
I mix roughly 4-5 minutes. I always set a timer for 4 minutes in case I get interrupted, and to be aware of how much mix time has occurred. This time isn't necessarily exact. You will know it’s mixed when there’s no striations following stirring. Scrape sides & bottom regularly. Once it’s fully mixed, Let sit in cup a few minutes. Bubbles may rise to top, and you can carefully use a heat gun over resin in the mix cup, for quick short spurts to help process of popping bubbles, before pouring. Be careful to keep heat gun elevated enough, that the forced air doesn’t force resin to splash out of mixing cup. If heat gun has a low speed setting that is better to use. You just need the heat to release some of the bubbles before pouring in to moulds.
Pour mixed iCoat CE4100HV epoxy slowly in to mould. I set my mixing stick on an angle, and pour the epoxy slowly down the mixing stick into mould. Wait a few minutes then pop bubbles. Some people prefer to let this first base layer set, before adding their flower arranging. When ready, carefully place your florals in desired places. Artist can decide their preference of when to place florals. Sometimes the base layer will have foil flakes, or glitter or a solid colour added for different background effects, and if that is the case then you would add your florals in the next layer after base layer has set.
Do not use a torch in your moulds. If needed, a very light fine misting of 99% isopropyl alcohol can be used to release any remaining bubbles. If there are bubbles along the edge of the mold, gently guide them away from the mould edge before popping them. It’s also a good idea to slide something soft along the sides where newly poured resin touches moulds. Often times tiny air pockets sit against the mould sides, & aren’t seen until after cure or demold. Running something (stir stick) gently along the mould sides can help release those stuck on sides so they float up, where they’re easily popped. (I did forget to do this on a few layers).
With this epoxy resin, use an Infrared thermometer gun, to check for epoxy in mould to return to room temp, before you add your next layer.
If too much volume of resin is used in a layer, resin can overheat, which can burn your florals & cause mould to fuse to resin (ruining your mould, flowers & piece).
Side view example of first layer to set the florals in place.
2nd layer: Here, I’m checking temp to see if this piece is ready to add 2nd layer. It has dropped below 82F, so it’s ready. This was Day 1, Sunday, photo taken 6:49pm.
Day 1, Sunday 8pm, 2nd layer added, HV 10oz/300ml
Side view layer 2, Day 1, photo taken 8pm
Top view layer 2, Day 1, photo taken 8pm
Day 1, Sunday at 8:04pm after pouring 2nd layer, 10oz/300ml, epoxy heats as part of cure process, so you can see temperature is higher during curing.
Day 2, Monday 7:29am, layer 3 added 10oz/300ml
video below is Day 2, Monday, 7:39am
quick video also Day 2, layer 3 added, 10oz/300ml, Monday, 7:48am
Day 2, Monday, 7:05pm, layer 4 added, 10ooz /300ml
Day 3, Tuesday 8:05am checking temp on previous nights layer 4
Day 3, Tuesday 8am, Layer 5 added. 10oz/300ml
Day 3, Tuesday 8pm, Layer 6 was added.
Here's where I decided to experiment with something and it did not work. I tried to fill the rest of the mould with resin, since not a lot of flowers/organics were above previous resin line, but it was too much depth. The resin started to go thermic (overheat) on me. I didn't want to chance ruining the brand new mould, and wasn't sure I could save the piece, but I started removing (scooping out) a bunch of resin as quickly as possible using a clean mix cup. I had a bit of a mess happening, but managed to remove enough resin that the temperature settled, and I ended up leaving that layer to cure overnight as it was. I new there would be some bubble issues, and possible wavy resin look from that layer partial removal, but better than ruining my mold for these experiments.
Day 4, Wednesday 8am, Layer 6 was re-added (or should I call it layer 6 1/2? lol). This time I went back to just using 10oz/300ml for this final layer. It didn't fill the mold to the top, but the flowers were covered enough, and I knew it wasn't going to be a perfect finish due to previous nights user testing error, so I decided this would be the final layer.
Day 5, Thursday about 12pm noon, I unmolded this 6x6x3 piece. And these photos below were taking about an hour later. The edges were not trimmed yet at time of these photos posted below, but has since been trimmed.
With my experimental error, the piece still turned out alright. It seems I was able to save the piece for the most part. These floral blocks are really truly beautiful even when not perfect. And as someone reminded me, the little imperfections just add to the character and home made touch of an artists love going in to each creation.
So as always, with florals, it's best to play it safe and pour shallower layers. Patience is hard when we just want to get the piece done, but it's so worth it to slow it down & be sure with floral projects.
Video clip of completed block. (Side edges not yet trimmed at time of recording).
Initially, I wasn't going to post my rookie errors (in this series of 3 blogs), but I decided to go ahead, as they become a learning opportunity for others who may not have experienced these issues yet either. And it might be months before I have the time to put together another blog post showing process photos and information. Here's hoping the next one goes without errors. ;)
For information on top-coating floral block pieces, please see the blog post Top-Coating /Flood-Coating Floral Pieces with iCoat.
ArtWorks Resin Canada