Custom cobot gripper jaws: when you need them and what they cost

When are standard fingertips not enough?

Standard fingertips and adaptive grippers are enough for a lot of pick-and-place work, and there's no reason to pay for custom jaws if the stock tips already hold the part reliably. Custom jaws start to earn their place in a handful of specific situations.

Odd or complex part geometry is the most common one — a component that flat or grooved stock tips can't locate or hold securely because there's nothing consistent for them to grip. Jaws contoured to the exact part cradle it properly instead of relying on friction and luck.

Slipping or marking is the second. Rigid tips can drop a part that doesn't have a good flat surface, or scratch and dent parts that need to stay cosmetically clean. A PETG jaw body with a textured TPU grip pad holds firmly without marring the surface.

Delicate parts need the same compliance for a different reason — too much clamp force damages them, but too little and they're not held securely through the arm's acceleration and deceleration. A jaw shaped to spread load across more of the part's surface, rather than concentrating it at a point, solves both problems at once.

And fast changeovers matter on lines running more than one part variant through the same cobot gripper — a dedicated jaw set per part is often quicker to swap than reprogramming a general-purpose grip for each one.

How are custom jaws actually built?

They're modelled from the gripper's own manufacturer CAD, not guessed from measurements of the physical part. The jaw's mounting face is built to match the gripper's fingertip interface and the ISO 9409-1 robot flange standard, so it bolts straight onto the fingers you already have without adapters or shims.

The jaw body itself is printed in PETG for structural rigidity, and a flexible TPU pad is bonded onto the contact face for grip and a small amount of compliance. If a part needs more strength than PETG, that's a job for machining or a metal part, not FDM. The whole design goes through a print-and-test-fit cycle against the real part before it's called finished, so the first set you actually keep is one that's already proven to grip.

Why does it matter where the jaws grip the part?

Where the jaw contacts the part is a design decision, not a detail that sorts itself out once the fingers close. A part that's only pinched across a narrow band can still rock or twist as the arm accelerates, decelerates or changes orientation through a real cycle, even though the jaws never actually opened — the grip looks secure at pickup and fails partway through the motion.

Robotiq's fingertip design guidance says to keep the grip surface below the equilibrium line — the point separating an encompassing grasp, where the finger rotates in and wraps the part, from a parallel grip that holds on the fingertips alone and is more easily ejected. Beyond following that placement rule, what actually keeps a part seated is contact area and fit — a jaw contoured to match the part's shape holds it across more surface than a flat or generic tip would, and the TPU pad adds friction and a small amount of compliance on top of that. This is settled during modelling and the print-and-test-fit cycle, against the real part and the real gripper, rather than fixed later by clamping harder.

How does pricing actually work for custom jaws?

Custom jaws are priced as a first article followed by production reorders, because most of the cost is in the engineering rather than the printing. The first article covers measuring the part, modelling the jaw to the gripper's mounting interface, and the print-and-adjust cycle until it grips the part reliably — that's a design job, quoted per job once we've seen the part and the gripper.

Once that design is proven, reordering the same jaw set is far cheaper, because the engineering work doesn't need repeating. Jaws and TPU pads are consumables (see the robotics and automation page for how that is planned into a cell) — order more of the exact same design whenever a set wears out or a line gets duplicated, at a per-set production rate rather than a fresh first-article price.

Why does it help to use a local, low-volume maker for this?

A run of a handful of jaws for one cell is a fine job for us and too small a job for most overseas end-of-arm tooling suppliers to prioritise. Minimum order quantities, freight time and the back-and-forth of getting a fitment right over email don't suit a one-off or a short production run. Being local means the part can physically be checked against the actual gripper, iteration is fast, and quotes usually come back the same day.

Frequently asked questions

Will custom jaws work with the gripper I already have?

In most cases, yes. We build jaws to fit Robotiq 2F-85, 2F-140 and Hand-E, and OnRobot RG2 / RG6, mounted on Universal Robots arms, and other gripper brands can be supported on request. Send the gripper model and we'll confirm fit before you commit to anything.

What do I need to send to get a quote?

A photo or drawing of the part the jaws need to hold, and the gripper model you're using. That's enough for us to suggest an approach and come back with a first-article price, usually the same day.

Can I get the CAD file for the jaws?

Yes, on request. We can hand over the source model along with the finished jaws so the design is documented and you're not locked into ordering reprints from us alone.

How long do custom gripper jaws last?

Jaw bodies and TPU pads are consumables, and how long they last depends on cycle rate, part weight and how abrasive the part is. Because the design work is already done, reordering a worn set is quick and priced at the lower per-set production rate rather than a full first article.