The Split Cup Journey
Earlier this year, I embarked on a creative journey to enhance my bait-making process. Intrigued by the potential of a silicone split-cup designed for epoxy resin, I decided to experiment with it for my open-pour bait designs. The results were intriguing but far from efficient. Due to the small size and straight sided walls of this silicone split-cup it simply would not fit inside of a standard glass measuring cup, so I attempted to use a disposable cup to add some support to this thin, flimsy split cup. This was more of an attempt to salvage hot plastisol, but it just turned into a disaster.
As you can see in the photos below, the heat from the plastisol melted the disposable cup, as expected btw, and made the process messy and, frankly, a bit hazardous. The swirl effect was really cool though, so I persisted hoping that the heat would cause the disposable cup to form to the silicone cup, but that never happened. After pouring about two cups worth of baits, I decided that I really liked the swirly-marble effect that I was getting, but the delivery method had to improve. It was time to seek a better solution.
My quest led me through various options. For years, bait makers have created their own split cups by using RTV silicone to permanently seal a previously made silicone sheet into a glass measuring cup. DIY split cups using RTV silicone seemed like a fun project, but messy and challenging to achieve a perfect 50/50 split at the same time. The idea of permanently altering my measuring cups for this purpose didn't sit well with me. Another suggestion was to find a ceramic cup to fit silicone split cups from Amazon that I already had. However, the thin inserts often held less than 1/4 cup of liquid per side, and at that volume, it wasn't an ideal solution.
Doing it myself
Being a maker at heart, I turned to Autodesk Fusion 360 to design a mold that I could then 3D print to produce perfect-fitting silicone split-cup inserts. It took several iterations to achieve the perfect fit for 1-cup, 2-cup, and 4-cup Anchor Hocking glass measuring cups as their geometry doesn't just scale up perfectly. The 4-cup mold, in particular, required a good bit of extra attention to detail until I had a split cup insert that would fit perfectly.
Sharing a video of the 1-cup, 50/50 split cup insert on social media generated unexpected interest. With several hundred bait-makers expressing interest Facebook, TikTok, and Instagram, things quickly became a overwhelming, and left me scrambling to get more molds printed to increase production capacity.
Initially, my 3D printing process was time-consuming, with 1-cup molds taking 12-14 hours and 4-cup molds exceeding 28 hours, plus additional cleanup time. A week of redesigning and testing led to a significant reduction in printing time. I'm now beginning to pour the initial runs of the 1-cup and 2-cup split cups, with 4-cup split cups rolling out in the coming weeks. Now with production beginning, I am finally able release these split cup inserts to the world.
What sets these inserts apart?
Each Silicone Split Cup Insert is meticulously molded from platinum-cured silicone, ensuring premium quality and exceptional durability with heat resistance up to 450°F. Precision 3D printed molds guarantee accurate reproductions of the original design, allowing for a snug fit inside standard 1-cup, 2-cup, and 4-cup Anchor Hocking Glass Measuring Cups.
You originally mentioned compatibility with the Pyrex brand of measuring cups. What happened to that?
As it turns out, Pyrex glass measuring cups have changed geometry over the years with slight, but not insignificant variations in roundness and the inner cavity’s wall angle. After trying these inserts in more than a dozen Pyrex brand measuring cups, I simply can not ensure the same fit with them as I can the Anchor Hocking brand. The 1-cup size inserts seem to fit well in Pyrex cups that are a decade or so old, but the 2 and 4 cup inserts seem to be different every cup. On the other hand, I have over a dozen of each size of the Anchor Hocking brand cups, some of them being 15-years old, and they fit perfectly every time.
This incompatibility between brands held this project up by a few weeks as I really wanted to work out a design that just worked, but after the initial success with a few 1-cup inserts fitting in a few Pyrex cups I had on hand, other Pyrex branded cups I bought to test with were just not compatible. I’m slowly buying and testing the fit in new off-the-shelf Pyrex brand 1, 2, and 4-cup measuring cups. If the current generation of cups hold a consistent geometry, I will produce molds to create silicone split cup inserts specifically for modern Pyrex brand measuring cups. As this brand is significantly more expensive than the Anchor Hocking brand, this process will take some time.
I know this will disappoint the diehard Pyrex fans out there, and I will continue to work on a compatible set of silicone split cup inserts. With that said, I can only ensure precise fitment in the Anchor Hocking brand of measuring cups at the moment. These cups are cheap and easily found at any Walmart store across America.
It’s also important to note that I can not confirm or guarantee fitment compatibility with ANY brand of measuring cup that is sold outside of the borders of the USA as I have not tested with anything but Pyrex and Anchor Hocking measuring cups sold in the US market.
So what do they cost?
Now, let's address the burning question: pricing. The 1-Cup Silicone 2-Way-Split Cup Insert will retail for $18, the 2-Cup variant for $28.00, and the 4-Cup variant (once available) for $35.
You can purchase silicone split cup inserts here!
Regular Pricing
- 1-Cup Silicone 2-Way-Split Cup Insert: $18.00
- 2-Cup Silicone 2-Way-Split Cup Insert: $28.00
- 4-Cup Silicone 2-Way-Split Cup Insert: $35.00 (Coming Soon)
Shipping Lead Time
As this is a made per order product at the moment, shipping lead times are about 8-10 days. In the near future we will be producing split cup inserts at a higher rate, and keeping them in-stock.
All packages will be shipped via USPS Flat Rate Shipping, with shipping fees calculated at the time of checkout.
Thank you for your support, and I look forward to enhancing your bait-making experience with these innovative silicone split cups.
