Why a Silicone Weight Won’t Stay in Place — And How We Fixed It
A customer recently came to us with a problem: a silicone weight we produced would not stay fixed in position. They asked us to find a solution and improve it.
This was a fairly new customer, but they were referred by an old friend. They brought us an existing mold that had been made elsewhere and asked us to produce the silicone parts. Their business is baby and toddler educational toys, so the material requirements are strict: food-grade silicone and platinum-cured silicone. (Chicarubber)
The part in question is a silicone weight for a balance toy. It needs to slide left and right along a wooden track. But when it is not being moved, it needs to stay put. That way, when the balance toy tilts, the silicone weight can grip firmly and hold its position.
The Challenge: Slide When Needed, Hold When Not
The silicone weight moves inside a wooden slot. The original mold was already made, and it did not include any features to help the weight stay in place. A smooth silicone cylinder inside a smooth wooden slot can slide too easily. When the toy tilts, the weight may shift on its own.
The customer needed the weight to do two things at once:
- Slide smoothly when a child moves it
- Stay firmly in place when the toy is tilted or left alone
Since the mold was already cut, we could not simply redesign the part from scratch. We had to work with the existing mold and find a practical way to improve the function.
Our Solution: Add Grip Ribs to the Existing Silicone Cylinder
We looked at the part and the mold, and we decided to make the most of what was already there. We modified the existing silicone cylinder by adding a few small ribs or ridges to the outside.
These ribs create more friction and contact pressure against the wooden slot. When the weight is pushed, it can still slide. But when it is not being moved, the ribs help it grip the wood and resist unwanted movement.
Because the mold already existed, we modified it locally instead of starting over. We then produced samples and sent them to the customer for testing.
Why the Ribs Help
Silicone is naturally grippy, but a smooth silicone surface does not always provide enough hold—especially against wood. Adding ribs changes the way the part contacts the slot:
- More friction: The ribs increase contact pressure against the wood.
- Better grip: Small areas of compression help the weight stay in place.
- Controlled movement: The weight can still slide when pushed, but it resists sliding on its own.
- No permanent lock: The ribs do not prevent movement. They simply make the movement more controlled.
For a balance toy, this is exactly what you want. The child can move the weight, but the weight stays where it is placed.
Why Material Matters for Baby and Toddler Toys
Because this part is used in a baby and toddler educational toy, the material must be safe and reliable. We used food-grade silicone with platinum curing. (Chicarubber)
Platinum-cured silicone is a common choice for baby products because it offers:
- High purity
- Low odor
- Good elasticity
- Consistent curing
- Reliable compression and recovery
These properties matter for parts that need to flex, grip, and hold their shape over time.
What We Learned
This project is a good reminder that for moving silicone parts, retention features should be considered early in the design. If a silicone part needs to slide but also stay in place, the mold design should include ribs, bumps, texture, or other grip features from the start.
But even when a mold is already made, there are often ways to improve the part without starting completely over. In this case, adding ribs to the existing cylinder gave us a fast, practical way to test a better solution.
Final Thoughts
A silicone weight that will not stay in place can make a balance toy feel unreliable. By modifying the existing mold and adding grip ribs to the silicone cylinder, we were able to improve holding power while keeping the sliding movement the toy needed.
If you are working on a custom silicone part for a baby toy, balance toy, or other application—especially one that needs food-grade or platinum-cured silicone—we can help with mold modification, sampling, and production.
Check out the photos of the silicone weight to see the ribbed design. Have a similar challenge? Contact us to discuss your project.
Why a Silicone Weight Won’t Stay in Place — And How We Fixed It
If you need to customize silicone products, please contact us at chicarubber
