Guides
Starlink Mini Rail Mount Sizing: Get the Pole Diameter Right
The Starlink Mini Boat and Rail Mount comes in ten pole sizes, from 5/8" up to 2". That range is why it fits everything from a sailboat pushpit to a deck post — and it’s also the one place an order can go wrong. A clamp sized for the wrong diameter either won’t close around the rail or won’t grip it.
Nearly every wrong-size order starts the same way: eyeballing the rail, or measuring it from a photo. Rails that look like 1" are often 7/8". There’s a 15/16" size in the lineup precisely because some rails miss the common sizes by a sixteenth of an inch.
Two minutes with a tape measure — or a piece of string — settles it. Here’s how.
The Ten Sizes
The complete mount comes in all ten sizes, and the base is also available on its own without a pole bracket. The wrap-around column matters more than it looks: if you use the string method below, you can read your size straight off the wrap-around measurement without doing any math.
| Pole size | Decimal | Metric | Wrap-around (circumference) | Pole runs parallel to |
|---|---|---|---|---|
| 5/8" | 0.625" | 15.9 mm | 1.96" (50 mm) | Short side of dish |
| 7/8" | 0.875" | 22.2 mm | 2.75" (70 mm) | Short side of dish |
| 15/16" | 0.938" | 23.8 mm | 2.95" (75 mm) | Short side of dish |
| 1" | 1.000" | 25.4 mm | 3.14" (80 mm) | Short side of dish |
| 1.25" | 1.250" | 31.8 mm | 3.93" (100 mm) | Short side of dish |
| 1.375" | 1.375" | 34.9 mm | 4.32" (110 mm) | Short side of dish |
| 1.5" | 1.500" | 38.1 mm | 4.71" (120 mm) | Long side of dish |
| 1.575" (40 mm) | 1.575" | 40.0 mm | 4.95" (125 mm) | Long side of dish |
| 1.79" (45.42 mm) | 1.79" | 45.42 mm | 5.62" (143 mm) | Long side of dish |
| 2" | 2.000" | 50.8 mm | 6.28" (160 mm) | Long side of dish |
The 1.5", 1.575" (40 mm), 1.79" (45.42 mm), and 2" brackets mount vertically due to size constraints — more on what that means for placement below.
How to Measure Your Rail
With a caliper: close the jaws on the outside of the rail at the exact spot you plan to clamp, and read the outside diameter. This is the most accurate method and takes ten seconds.
Without a caliper: wrap a piece of string, a paper strip, or a flexible tape snugly around the rail once. Mark where it overlaps, lay it flat, and measure the length. That’s the circumference — find it in the wrap-around column above and you have your size. If your string measures about 2.95" (75 mm), your rail is 15/16", not 1", and that sixteenth is the difference between a solid clamp and a loose one.
Holding a tape measure across the face of a round tube is the least reliable way to do this — the curvature makes it easy to read a sixteenth or two small. If the tape is all you have, measure the circumference, not the width.
Three more rules that prevent bad orders:
- Measure at the exact clamping spot. Rails change diameter at bends, welds, and fittings, and a boat can carry two or three different tube sizes between its bow rail, stanchions, and radar arch.
- Measure the rail you’ll actually use. Pick the mounting position first — clear sky view, reachable for the quick-release — then size that section.
- If you land between sizes, stop. Don’t round up and hope. Remeasure with the string method, and if it’s genuinely between sizes, contact us with your measurement before ordering. That’s exactly how the 1.575" (40 mm) size joined the lineup — a customer’s rail landed between our sizes, and we designed a new bracket for it.
What “Mounts Vertically” Actually Means
The size list says the 1.5", 1.575" (40 mm), 1.79" (45.42 mm), and 2" brackets mount vertically. That is a statement about the bracket, not your rail: on those four sizes the pole passes through the bracket parallel to the long side of the dish, where the six smaller sizes run it parallel to the short side. It comes from the size of the bracket, not from any rule about where it goes.
So it does not mean you need a vertical post. Every one of the ten sizes clamps a horizontal rail run, a vertical stanchion or post, or anything in between. What changes is how the Mini sits on the pole: with the four largest sizes, the long edge of the dish runs along the pole, so check clearance around your chosen spot with that footprint in mind. Either way the dish itself rides the same: pull back the dual spring plungers, slide the Mini on, and it snaps into place, with the same quick release when you’re coming into a marina.
For the full install walkthrough — positioning for sky view, clamping without crushing thin-wall rail, cable routing on deck — see the boat rail install guide.
One Mount, Many Rails: the Bracket Swap
The mount is two pieces: a base bracket that holds the Starlink Mini on its spring plungers, and a pole bracket that clamps the rail. They join with six black-oxide M5 screws and a 4 mm hex wrench — which means the pole bracket is swappable.
The add-on pole bracket sells on its own in all ten sizes, with its six M5 screws included. If your dish moves between a 1" boat rail and a 1.25" dock railing, that’s one full mount plus one extra bracket — not two complete mounts. The same part is the answer if a bracket ever gets damaged: replace the piece, not the system.
The brackets are ribbed internally for grip on the rail, and every one of them mates with the same base bracket, so the swap is six screws and nothing else.
Salt, Sun, and Spare Parts
The mount body is UV-resistant ASA — the same material we print everything in, chosen for years of sun exposure — and the hardware is black-oxide alloy steel M5 screws with zinc-plated spring plungers. Salt water attacks any fastener finish over time, so do what the boat guide says: rinse the mount and hardware with fresh water when you rinse the boat, and pull the dish before marinas, bridges, and rough weather.
Screws, plungers, and brackets are all sold individually in the spare parts collection, so a dropped screw at the dock is a spare-part problem, not a new-mount problem.
Like everything we make, the rail mount is designed and printed in-house just outside Atlanta, Georgia, in black or white. Production takes 1–3 business days, domestic shipping another 3–5, and we ship internationally.
Related Guides
- How to Mount Starlink Mini on a Boat Rail — the full install, once your size is on order
- Starlink Mini Mount Buying Guide: Suction vs. Screw-In vs. Magnetic — if you’re not sure a rail mount is the right type at all
- UV Protection for Outdoor Starlink Mounts — why ASA handles years on deck
Measured your rail? Browse all Starlink mounts and enclosures →
