Silicone Prototyping: Clean Fingers Shellfish Eating Glove

A three-finger sleeve taken from a Louisiana inventor's idea to functional silicone prototypes ready for user testing.

CONCEPT DESIGN
ERGONOMIC DESIGN
MATERIAL SELECTION
3D PRINTING
SILICONE MOLDING
PROTOTYPE TESTING

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Written by Ralph Hill, Mechanical & electrical systems, 3D manufacturing

Prototyping Engineer

Published August 30, 2026

Project snapshot

Megain and Tineaia Comanche came to LA NPDT with an idea for a three-finger sleeve that keeps your thumb, index and middle fingers clean while peeling crawfish and shrimp. We designed the ergonomics, selected the material, and delivered functional silicone prototypes they could test with real users.

The LA New Product Development Team delivered Silicone Prototyping: Clean Fingers Shellfish Eating Glove, covering concept design, ergonomic design, material selection, 3d printing, silicone molding and prototype testing. Our in-house team handles concept design, engineering, prototyping and manufacturing readiness under one roof in Ruston, Louisiana.

Services applied: CONCEPT DESIGN, ERGONOMIC DESIGN, MATERIAL SELECTION, 3D PRINTING, SILICONE MOLDING and PROTOTYPE TESTING

Clean Fingers is a soft, reusable sleeve that slips over the thumb, index and middle fingers so you can peel and eat crawfish, shrimp and other shellfish without coating your hands in shell, spice and juice. A strap across the back of the hand holds it in place, and textured fingertips give you grip on a wet shell.

Megain and Tineaia Comanche, sisters and inventors based in Louisiana, brought us the idea and one clear requirement: they wanted to hold a real, working version in their hands as fast as possible. That made this a feasibility and proof-of-concept program rather than a full production build. Our team handled concept design, the ergonomics, material selection and rapid prototyping, and delivered functional silicone units the sisters could put in front of their own potential customers.

The Brief: Bare Hands, Full Gloves, or Something In Between

At a Louisiana crawfish boil the two normal options are both compromises. Bare hands peel well and feel right, but everything you touch afterward — your phone, your drink, someone else's plate — pays for it. Disposable gloves keep you clean and kill the dexterity and the feel that peeling shellfish depends on, and they get thrown away by the handful. The sisters wanted a middle path: cover only the fingers that actually do the work, leave the rest of the hand bare, and make it reusable.

Only three fingers. The thumb, index and middle fingers do the peeling; covering the other two adds bulk and heat for nothing.
Dexterity has to survive. The wearer still needs to feel the shell and find the seam, so the wall had to be thin and the material soft.
Grip on a wet shell. Shellfish are slick, so the fingertips needed texture rather than a smooth molded surface.
One size has to fit most hands. A consumer product sold at retail cannot ship in six sizes on day one.
Reusable and washable. The whole point is that it is not another box of disposables.
Cheap to make. The retail price this product can carry is small, so the part had to be manufacturable in one piece.

Designing for Hands Is Harder Than It Looks

Anything worn on the body pushes product design into ergonomics, and hands are one of the least forgiving places to start. Finger length, finger diameter, web spacing and knuckle position vary enormously from person to person, and the same hand changes shape completely between an open palm and a pinch. A shape that fits snugly on one hand can be tight enough to cut off circulation on the next or loose enough to slide off mid-peel.

We resolved that with three decisions taken together. The geometry was designed around the closed, pinching hand rather than the flat hand, because that is the position the product is used in. The material was chosen to stretch and recover so a single size could absorb a wide range of finger sizes instead of matching one. And the fit was made adjustable at the wrist and back of the hand with a perforated strap, so the wearer sets the tension themselves rather than relying on the sleeve gripping the fingers.

Clean Fingers prototype shown flat on an open hand with the perforated adjustable strap across the back of the hand — The perforated strap sets fit per user — the reason one molded size can cover a wide range of hands.

Close view of the Clean Fingers silicone prototype fingertips showing the molded grip texture for holding wet shellfish — The perforated strap sets fit per user — the reason one molded size can cover a wide range of hands.

Material and Process Selection

Silicone prototyping was the right answer here because the properties that make the product work — softness, stretch, recovery, washability and food contact — are the properties a rigid 3D print cannot demonstrate. A printed part tells you whether the shape is right; only a cast elastomer tells you whether the product is right. We used both, in that order, moving from printed form studies to silicone rubber molding in printed tooling.

3D printed form studies. Fast, cheap checks on finger length, web geometry and strap placement before committing to a mold.
Printed molds, cast silicone. Molds were printed and finished in-house, then filled with platinum-cure silicone to produce functional units in days rather than weeks.
Durometer selection. Several hardnesses were evaluated against the tension-versus-comfort trade-off; too soft tears at the web, too firm fights the hand. Hardness is measured on the ASTM D2240 Shore A scale, and a few points either way changes how the part feels on the hand.
Food-contact material. Because the product touches food, the material path was chosen from silicones that can meet FDA food-contact substance requirements at production.
Single-piece geometry. The sleeve, the fingertip texture and the strap features were designed to come out of one mold, with no assembly and no secondary operations — the single biggest lever on unit cost at volume.

Iterating to Functional Prototypes

The program ran in short loops. Each round produced a wearable part, went onto several different hands, and came back with a specific correction: a finger shortened, a web opened up, a wall thinned, a strap moved. After a couple of design iterations and a few rounds of prototypes, we delivered functional units the Comanche sisters could wear at an actual boil and hand to other people for feedback — which is exactly what a proof-of-concept prototype exists to do.

Because design, engineering and prototyping all run under one roof in Ruston, Louisiana, those loops were measured in days. Nothing waited in a queue between an outside design firm and an outside model shop, and the engineer who changed the CAD was the one who pulled the next part out of the mold.

What the Client Received

Ergonomic industrial design and production-intent CAD for the three-finger sleeve
Material and durometer selection, including a food-contact-capable path to production
Single-piece, moldable geometry with integrated fingertip texture and strap features
3D printed form studies across several iterations
Printed molds and cast silicone functional prototypes in multiple rounds
Wearable units delivered for the inventors' own user testing and market validation

If you need custom silicone parts, a wearable, or any soft hand-held product idea proven out before you spend money on tooling, our Ruston, Louisiana team can take it from sketch to a part you can wear. Crawfish season peaks across Louisiana each spring, and this product had to be ready for it — tell us about your product and we will map the fastest honest route to a testable prototype.

Capabilities used on this project

Rapid prototyping services
3D printing, CNC machining, urethane casting and functional prototype builds with published materials, tolerances and lead times.
Concept design
Sketch exploration, form studies and CAD concepts that turn an idea into a buildable direction.
Low-volume manufacturing
Bridge tooling, short-run production and supplier management for first commercial batches.

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Project snapshot

The Brief: Bare Hands, Full Gloves, or Something In Between

Designing for Hands Is Harder Than It Looks

Material and Process Selection

Iterating to Functional Prototypes

What the Client Received

Capabilities used on this project

Rapid prototyping services

Concept design

Low-volume manufacturing

Outdoor Gear Design: Fall Arrest Hunter Safety Device

Apparel Prototyping: Kool Pressions Therapeutic Compression Leggings

IoT Product Development Services: Sysdyne Delivery Sensor

Tell us about your product idea