How to Design a Custom Phone or Tablet Mount
Off-the-shelf phone mounts never quite fit — wrong angle, too loose with a case on, or no bracket for your desk, bike, or dashboard. A custom mount solves all of that, and it is one of the most satisfying things to design and 3D print. This walkthrough covers how to measure your device, how much clearance to add, how to think about the clip and the arm, and how to generate the whole thing without learning heavy CAD.
Step 1: measure your device (with its case)
A mount is only as good as its measurements. Grab calipers if you have them, or a ruler, and measure the phone or tablet as you actually use it — with the case on, since that is what the mount has to grip.
- Width across the device at the point the clip will grab it.
- Thickness (depth) including the case — this is the gap your clip must open to.
- Button and port locations so the clip does not cover the power button, volume keys, or charging port.
- Camera bump if the back is not flat — leave room or a cutout.
Write the numbers down
You will feed these straight into your design. If you are designing for a phone that is 76 mm wide and 9 mm thick with a case, those two numbers drive the whole clip.
Step 2: clearance and grip
A mount that is exactly device-sized will be impossible to insert. You need clearance so the phone slides in, plus a little give so it holds without cracking.
Slot width
Add about 0.4–0.5 mm to the measured thickness so the device drops in. A cradle that grips the long edges should match the device width plus a hair.
A flexible clip
For a spring clip, keep the gripping arms thin enough to flex (around 2–3 mm wall) and let them open slightly wider than the device, so they squeeze back and hold.
Add a soft contact
Recess a strip for a thin foam or rubber pad where the phone touches plastic. It protects the screen and improves grip without tighter tolerances.
A lip or backstop
A small lip along the bottom edge keeps the device from sliding out, especially for a tablet, which is heavier and wants to tip forward.
Holes and slots print undersized, so the same clearance thinking applies to any screw bosses in the arm. For the exact values that make printed features fit, see tolerances for 3D printed parts.
Step 3: the arm and the base
The cradle holds the device; the arm and base decide where it goes. Pick the mounting situation and design the back of the mount to match:
- Desk stand — an angled foot (around 60–70° from horizontal) with a wide base so it does not tip.
- Clamp or bracket — a slot or screw holes to bolt onto a shelf edge, monitor arm, or wall plate.
- Round-bar mount — a curved cutout sized to a handlebar or tube, with a screw to clamp it.
- Standard ball joint — design the cradle to bolt onto a common ball-mount head if you want adjustable angles.
Keep the wall thickness around 3–4 mm anywhere the mount carries load, and add a small fillet where the arm meets the base so it does not snap there. New to fillets? See how to add a fillet or chamfer.
Generate your mount in your browser
Rather than model every curve by hand, describe the mount to PartWork.ai using your measurements. For example: “a desk phone stand for a phone 76 mm wide and 9 mm thick, tilted 65 degrees, with a cable slot at the bottom and a wide base.” Then refine — “make the base 10 mm wider” or “add screw holes to wall-mount it.”
Start with 2 free AI generations — no card required
Open the studio, describe your mount, and export an STL to print it tonight. More credits: 100 for $4.99 (~5¢ each).