I improved upon my box design for the object to go into by making it a hexagon. This was done so the object could be placed in the middle of the box on a stand. The first box design allowed users to place their hand into the box, pick up the object and then feel it with the entire surface of their hand. They could also get a good idea for the size of it and all the surfaces of it.
This new design meant that while it gave access to all the sides of the object, the smaller holes and the use of moderately stretchy fabric placed across the holes so that the fingers could only fit through the slit in the fabric would make it more challenging.
I also played around with the idea of gloves made of different materials that would slot into place around the hexagon and provide a layer of interference, with one hole left gloveless. The user would then place their hands into the fingers of the gloves to touch the object. I wanted to see if different materials and thickness of materials, such as latex and rubber gloves would make it more difficult to get a feel for the object in the box than with just bare fingers.
I added a second box to the design for the user to do the sculpting phase of the interaction in. This was so they had no visual feedback about what they were sculpting and had to rely completely on tactile feedback. This has taken nearly all the visual feedback away. There is still the feedback gained from seeing an accurate sculpture that someone has done. Although, given that only the user will know if they sculpted an accurate model or not, but people do tend to give that sort of thing away through facial expressions.
My second prototype took into account the feedback I received from my tutor and others who tried the first prototype out, I also incorporated some ideas I had for expanding the design. Once again I used very simple materials of card, masking tape, aluminium rod, material and air-drying clay for the prototype.
I decided that it might be good to have more than one object that could be placed in the object touching box so that they could be swapped around. Which might get around the issue of once one person had sculpted a good likeness, others were likely to use that sculpture as a basis for theirs as opposed to what they felt inside the box being the basis.
So I made some simple clay shapes, as I had also been advised that if the object was too difficult to get through feeling that users would give up.
I then made some stands using 3 layers of card. The bottom piece had a hole cut out to act as stabilizer both outside and inside the touch box. I glued a square of the same size but without a hole to that and then I glued a third smaller square to the second layer. I then drove a length of aluminium rod through the top two layers of card to act as the stand for the clay object. When the objects were dry enough, I pushed them on to the top of the rods.
I made some boxes to fit over the top of the objects and their stands so that the objects wouldn’t be seen until after they had been used. The idea was to have a lid on the top of the touch box that you would place the object’s box over and then push the object into place within the touch box. The bottom layer of the base slotted into a corresponding slot in the bottom of the touch box.
This idea didn’t go to plan as I keep having difficulties figuring out how exactly to keep the object in the box and then how to push it into the touch box without it ever being seen. I left the prototype as is and decided to keep thinking about the logistics of it in the meantime.
I did a couple of prototypes of my box design in the end. I didn’t get round to making a cylinder shaped one though as I decided on hexagonal instead.
My first cardboard prototype was a very basic box-shape with only two holes on either side and some gauze attached so you couldn’t see the heart bottle very well just by glancing through the holes, and all stuck together with masking tape.
The idea behind the first prototype was simple: put your hands in the box and get a good feel for the object ( without looking ) and then grab some plasticine and sculpt what you think you felt. You didn’t have your hands in the box for sculpting and so could compliment the tactile qualities of sculpting what you felt with visual feedback on how it was looking based on what you thought you felt. You then could have a look in the box to see how your model compared to the object.
People who tested this prototype did well at sculpting a likeness of the heart based on what it felt like in the box. There was one person who didn’t get it even close, sculpting something which resembled a starfish instead. Depending on how much effort was put in to exploring the heart object in the first place and then also time spent on sculpting corresponded with how accurate the finished model looked. Most users did a sort of sketch model and our tutor Steve did the most accurate model of the bottle. He did spend quite a while feeling it and then even longer sculpting it.
I think being able to have that visual feedback when sculpting made the task easier in terms of getting a decent representation of the object that couldn’t be seen. Also, as there was only one object to sculpt, as soon as someone got it right, everyone knew what they were suppose to sculpt. I don’t know if this had a bearing or not on what people think they felt and what they sculpted but I do hope they tried to sculpt what they think they felt.
All in all, the reaction to my design concept seemed positive in contrast to the other concept I had bought along which was the mood enhancement stress balls. Given that I decided to progress with the idea.
I have attempted this phase four times in all, and none of them worked out the way they needed to. I had the same issue with every resin casting I did. The surface exposed to the air would dry perfectly and was as smooth and glossy as polished glass, and then I would release the cast from the mould and the surfaces that were touching the mould were sticky and not set properly. It was only the surface that came into contact with the mould that wasn’t set, the rest of the resin seemed solid. It’s very odd, but only because I haven’t contacted the suppliers of the products to see if they know the reason I am having this issue every time I cast, given that I have varied what I have done to the inside surface of the mould. So I can only surmise that it is either the rubber mould itself reacting with the resin, or the total occlusion of air between mould and resin that is the issue. The other problem had been a small air bubble trapped between the cast and the mould where the neck of the bottle was. I think creating a mould where the bottle neck was down at the bottom of the mould and the opening for pouring would be the base of the bottle, (so upside down (as it is at the end of video clip)), would have solved the trapped air issue.
I had read online throughout this learning about failure with resin casting and the use of rubber moulds. I couldn’t find a lot of information on why it was not curing properly but most of the opinions were that resin didn’t set because of exposure to air. However the problem that I was having was the opposite, the air exposed surface dried and the surfaces that were against the rubber mould remained tacky, even after being left for over a week in the air. Regardless of whether there was no release agent, only release wax as the agent or the wax and polyvinyl alcohol (PVA) release agent, the surfaces exposed to the rubber mould didn’t cure properly, and it only seems to have been a few millimetres affected. I assume that either the resin and rubber interact somehow regardless of agents between them or it had something to do with my resin to catalyst ratios and the mixing of them, and possibly the fact that my cast was very thick.
I tried sanding off the tacky layer it wasn’t easy and didn’t work all that well, so I found workaround. Someone online suggested using the PVA agent to coat a tacky casting to protect it from air so it would harden properly on its own. I coated a couple of the resin hearts in the PVA and washed it off after about a day only to find that the surfaces were still tacky to touch. Yes, it was a frustrating process, but hey, what was I going to do? I wanted a resin heart and needed to find a way to have one. If it had come to it I would’ve done a plaster one as a last resort. Thankfully, I discovered that when the PVA dried after I had covered the hearts in it, the surfaces no longer felt sticky.
Pebeo Gloss Varnish
I had bought some gloss varnish (for resin) to coat the hearts in after and though it didn’t cure my stickiness issue when applied to the surface of the heart directly, when applied on top of the PVA layer, it seemed to work fine. So the heart I placed inside the box has a layer of PVA and then several layers of the gloss on top as protection, so it is tack-free. Not perfect but a pretty good fix under the circumstances.
As for success in future resin casting, I am going to contact the manufacturers to see if they have any pointers and then I am going to nail resin casting to the wall! In other words, I am going to end up with a properly cured piece so I can add successful resin casting to my list of skills.
I caved and bought some polyvinyl alcohol (PVA) release agent, as from what I read from various online sources it creates a nonreactive film between the mould and the resin.
I had to re-melt the rubber to make another mould. My last mould!! I left this one over night after I had released the bottle from it to make sure it was dry, though I am not sure doing this even mattered, but it certainly didn’t make things worse.
The next day I applied several layers of the release wax, in the usual way, just like the instructions on the tin. I left it to dry for a few hours after the last layer. The wax still wasn’t shiny in some places, but in other places it had a nice gloss, so I was fine with that. It seemed like I wasn’t going to get it glossy all over, no mattered how many layers I applied or how many times I made the resin object.
After it had dried, I applied a thin layer of the PVA over the entire inside surface of the mould using a small soft paintbrush. The directions on the bottle said the best method was with a fine misting spray bottle (I didn’t have one), or to use a soft cloth, but given the nature of the mould, specifically the bottle neck, a cloth would have missed areas. I’m pretty sure I only needed to apply one coat but I applied three because of concerns about the resin not curing properly the other times. I left each layer to dry for about an hour before I applied the next coat and then left it overnight again to make sure it was properly dry.
I would love to say that it worked and the resin was properly cured all over this time. It wasn’t. It was just like the previous casts, exposed surface cured, unexposed surfaces tacky to the touch.
I bought some more rubber and made two moulds; using the new rubber to make one, and cutting off the surfaces from the last one and re-melting the rubber to make another.
On one, I used the release wax. This time to prevent stray fibres I used a paintbrush to apply the wax and a micro fibre cloth for polishing. This worked better as there was less fibre on the mould but it was still dull looking. I also applied several coats instead of just two.
I left the other mould free from any release agent, so the resin had direct contact with the rubber itself.
I also used two brass rods in each cast for the supports to help make it more stable once placed in the box.
Unfortunately, I had exactly the same problems on both moulds, the exposed surface cured perfectly and the unexposed surfaces had a few millimetres of not fully cured resin that were quite tacky to the touch.
I applied the release wax to the first mould I made. The instructions said to apply several coats, polish each coat to a shine and wait for 10 to 20 minutes between coats. Then leave for two hours to dry. I couldn’t get the couple of coats I applied to shine and was instead left with a dull looking surface that had bits of the soft cloth I was using stuck to the mould. So I washed the mould out with hot soapy water and then left it to dry before I poured the resin in. I left the resin to set for around 12 hours and discovered the sticky surfaces when I released it from the mould. Leaving it out in the air for a night didn’t help the surfaces to set and they remained sticky. I had only used a single brass rod to support this cast which was not sturdy enough, and with the sticky surfaces, I decided to try again.
A more indepth description of the mould making process
Materials Used:
Reusable moulding rubber
Aluminum pan (Must be aluminum, not stainless steel or non-stick or for that matter bain-marie style).
Plastic container (to hold object for casting and rubber)
An object for casting. In this case a heart-shaped bottle.
Method:
Cut the rubber into tiny bits, mine were around a centimeter cubed.
Put aluminum pan onto hot plate to heat up.
Turn the heat down to medium-low.
Add a handful of rubber to the pan and stir until around half of it has melted.
Add another handful, and repeat the instruction above.
Do this until all rubber has been added.
Keep stirring the rubber continuously to make sure it doesn’t burn, and stir until smooth and all the rubber has melted.
Take the pan off the heat to cool the rubber slightly for a couple of minutes and allow air bubbles to rise to the surface. Continue to stir the rubber slowly.
Make sure the object you want to cast is in the plastic container.
Start to pour the rubber smoothly, evenly and at a constant speed into the container between the container and the object. Don’t pour over the object to begin with as this may introduce air bubbles into the surface of the mould touching the object. It’s okay to pour over the object once the rubber has risen up the sides and flowed over it while pouring inbetween the sides of the object and container.
Once entirely covered leave it to set. I usually leave it for an hour or two. It doesn’t seem to take long to set but it’s better to err on the side of caution than potentially ruin all that effort.
Take the mould out of the container and remove the object from the mould. Leave to cool.
Yet another first for me with this project, and therefore probably not the wisest of moves but hey, gotta learn how to use the new sometime in life, right? As with most firsts in life, this one was unlikely to turn out right the first time. I used gloves during this phase due to the warnings on the tins and bottles (which is strange for me as I usually have a cavalier attitude in regards to safety warnings), and the incredible chemical smell that emanated from the tin of Klear-Kast when I opened it. I achieved a massive headache from this phase despite having an open window in front of me. So be warned… Resin is evil-smelling.
The ingredients for resin making
Norski Klear-Kast Resin
Norski MEKP1 Polyester Resin Catalyst
Norski Colour Dye in red
Steps I took for the making of the resin heart
Poured 125ml of Klear-Kast ( not enough as it turned out ) into a glass measuring cup.
Added the red dye drop-by-drop until I achieved the depth of colour I required, and stirred until mixed to where I wanted it.
I added 8 drops of the catalyst per 30mls of Klear-Kast, and mixed for around two minutes until it looked thoroughly mixed.
I left it to stand for three minutes to get rid of the bubbles.
Then I poured it into the rubber mould and left it for around 12 hours to set.
The top exposed to the air the entire time set nicely, however when I took it out of the mould the other sides of the heart were still sticky.
The sides haven’t set at all and so I am going to have to make another mould and recast the heart. I’m not sure why they didn’t set, I suspect there is a few things it could be. I may need to put more of the hardener (catalyst) in to the resin, or more likely it could be the release wax wasn’t set, or I should just not use it, or the mould was still damp from the wash I gave it or somehow the rubber mould was compromised in some way. The instructions on the resin said to make sure the mould was free from dust, waxes, etc, so it is likely that it is the wax that was the problem.
I improved upon my box design for the object to go into by making it a hexagon. This was done so the object could be placed in the middle of the box on a stand. The first box design allowed users to place their hand into the box, pick up the object and then feel it with the entire surface of their hand. They could also get a good idea for the size of it and all the surfaces of it.
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Page-Sinclair First Year Design 