Great Cakes Soap Challenge Club Impression Mat Challenge*

 *(December 2015)

This soap was created for the December 2015 Great Cakes Soap Challenge Club “Impression Mat Challenge”. This entry was originally posted on my Pinterest board and I have recreated it here for the purpose of my blog.

Cute as a Button




This month’s challenge for Amy Warden’s Soap Challenge Club was “impression Mats”. The objective was to create a soap using an impression mat to create a design on the top of the soap. We could either use a pre-made mat or make one ourselves. Of course, I wanted to try to be as original as possible (read: create as much work for myself as possible) so I made my own. I had been designing this soap in my head since October, after Amy announced the next three month’s challenges. With so much time to think about it my design became more intricate and detailed as time passed. My final soap may look rather simple but it was a true effort to actually create! Despite the middle embeds not having stitch holes to make them appear more realistic, the design turned out pretty close to what I’d envisioned!

Beginning The Design Process/First Mold Attempt

The idea first came to me as I was sewing a button on my husbands pants. I have a huge bag containing hundreds of buttons I have been collecting over the years. I never really had found an ideal use for them beyond using them for various sewing projects…until now! My pack rat traits looked to finally be paying off! As I looked at the bag with the numerous variety of buttons the design began to form. 

I decided to create a soap that looked like it had real buttons on the tops. In the tutorial, Amy had shared with us a way to use silicone rubber to mold objects to use as the impression. To achieve the appearance of buttons, I needed a negative impression mat, one I could fill with a contrasting soap to create the buttons. I decided to use a product called Oomoo-30 for my silicone mold. It is a high-tear type of silicone rubber (does not tear easily) and can stand up to lots of uses.


Oomoo-30 Silicone Rubber

One of the grand design ideas I initially came up with was to create the appearance of fabric under the buttons. In the tutorial, Amy had used a mold making product that wouldn’t work on any type of fabric. I hoped Oomoo-30 would be different. The instructions had a telephone number to call the company for help so I did. I talked to a rep and he suggested coating the fabric with a thin layer of Vaseline first so it wouldn’t stick. I did an initial test with a very small piece and it worked perfectly.

I began by hot gluing Popsicle sticks to a clear piece of acrylic to form a frame to hold the silicone. I ran an extra line of glue around the outside edges to ensure there was an adequate seal without any gaps or holes for the silicone to seep out.



I then hot glued fabric, rick-rack trim and buttons to the inside of the mold. 

First try


Now…the fun part! Some silicone molding mixtures are different but with Oomoo 30, you mix an equal amount of Part A with Part B and combine until the mixture is uniform in color. This provided a very easy way to tell if it was all mixed properly.


Oomoo 30 gives you a whole 30 minutes of working time before it sets up. I chose this one because I wanted as much time to work with the mixture as I could if I ran into problems. I quickly discovered I didn’t need anywhere near that amount of time. This particular variety also has a 6 hour cure time, which in the world of an impatient soap maker, might as well be an eternity! Oomoo also makes a different variety of the same product but it sets up in 15 minutes and it cures in 75 minutes. It is called Oomoo 25. That’s what I will be using next time.

After it was thoroughly mixed, I poured it over my buttons. The white paper with the lines you see under the buttons is a guide I taped under the piece of acrylic. I wanted to be able to gauge the placement of the buttons to ensure proper distribution when the loaf was cut into individual bars.

Mold Pour


Mold after pouring the silicone. Sorry for the poor image quality!


This first mold attempt didn’t go very well. After gluing on the fabric and trim, I went crazy trying to be as creative as possible with my buttons. Amy’s instructions saying the objects should be “mostly flat” obviously didn’t sink in! It was a neat collage, but pretty much unusable as an impression mat. I also had completely covered my fabric in my button gluing frenzy so there wasn’t any peeking through! The rick-rack along the edges did come through pretty well, however.

Mold 1

You can see why Amy said the items being molded should be flat. Here, you can see where I had put buttons on top of others and how that resulted.


Second Mold Attempt

Back to the molding board. This time, I didn’t use the fabric and made a more uniform layer with the buttons. This attempt went much better but the buttons I used were pretty thin and did not give me the level of depth and detail I wanted.

Mold 2 Pour

Mold 2

Third Attempt

On this last mold, I wanted to try the fabric again. This time I divided the area into nine one inch sections and then glued 1″ burlap ribbon into each section. I also chose the thickest buttons I could find that were also mostly flat. Unfortunately, I did not use enough Vaseline on the burlap so it did not release as well as I had intended. It left behind small pieces of the rubber in the fabric and tore a little bit in some places too. Overall, it worked pretty well and resulted in more of what I was hoping for.  

Mold 3

Button Embeds

For the body of the soap, I wanted to create embeds that looked like buttons. To create these, I cut PVC tubing into small sections and placed a cap on each end. In my initial design plan, I wanted the button embeds to have small black circles in the center to give the appearance of stitch holes. I attempted to do this by putting bamboo skewers in each pipe after they were filled. Once hard, I intended to remove the skewers and fill the holes with black soap. This did not work out at all. The holes were not straight and some didn’t even go all the way through.

Embed Pour

Buttons w-holes


Filling Buttons


I ended up grating them all up into confetti and mixing them into the next batch to create texture.

Button Embeds


The Impression Mat

Next step was to fill the button impressions of mat I had created. I decided plastic squeeze bottles would probably be the best bet to get the soap into the small areas. After preparing several different squeeze bottles by mixing mica and a little water, I made a small batch of soap and poured a little of the batter into each bottle. After filling each button, I left it alone to harden for a few days.Filling 2


This is actually a photo of my first attempt, not the actual one I used. When I mixed the micas I used a little too much water and a few of the buttons were really watery. The next day they had shrunk quite a bit in the mat so I had to start over.

Design Tools 

One of the elements of my design was to create the appearance of rick-rack trim. I had seen a technique several months ago that Clara Lindberg from used to separate the soap into different colors. She used a notched spreader like this one – which is typically used to spread adhesives for home improvement projects – to shape one layer of soap before pouring a different color on top of that. I thought this might be a great way to create the rick-rack effect in my soap. I made a rick-rack “scraper” by gluing some of it to the bottom of a piece of cardboard. This served a couple of purposes: 1) to reinforce and stabilize the cardboard, and 2) to give me a guide for cutting the rick-rack shape.  


As usual, the side of my brain that comes up with these creative ideas doesn’t fully communicate with the side that actually does the work! When I planned the design, I don’t think it really sunk in how much time and labor would be involved in the whole process! After creating the impression mat, making the button embeds, and filling the button mat, I had to then create the layers. Not only did each layer of this design need to be created individually, I also had to wait for each layer to become firm enough to hold its shape after scraping. This translated into six separate batches. It took me the entire day to pour the whole thing.

Pouring the Layers

Since the purpose of the challenge was to create an impression on the top of the soap, I needed to reverse the normal order of pouring. The bottom of the mold was to become the top of the soap so I placed the filled mat face up in the bottom of my mold. I really liked the look of the burlap ribbon under the buttons so that is the color I chose to go with first.


I also drew out the design and taped it to one end to use as a guide while I poured. After each layer I waited about 45 minutes or so for it to firm up enough to scrape.

 *Edit: I have learned a lot more since this was first created. I will now use a fast-moving recipe and/or a fragrance that accelerates so I do not have to wait so long to be able to scrape each layer! 

First Denim








I added a contrasting color to help create the color variations of the threads in denim.

I apologize for not getting a photo of each pour and each scrape as well as the placement of the middle embeds. I was kind of sick of soap by the end of this day!


The Result!


Loaf before cutting.

Individual bars stacked.

Individual bars stacked.

Final 2

My entry!

This was a wonderful challenge because I now have learned a technique that I am sure will play a part in many of my future soap designs. I already see “impressions” in almost every thing I look at around me! I also would like to perfect and expand on the scraping technique. That in itself has endless possibilities!


Thanks for stopping by!

Until next time…


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Lisa Melli Gillespie
May 30, 2016 10:24 pm

Debi – SO COOL! I’ve been wanting to try out the impression mat design technique – got all the materials and bought the tutorial – but because the challenge was at a busy time of year, I never quite got around to doing it. Now I’m inspired again! Yay

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