Owner's guide
Putting Arc MS-3D
Setup & Practice Guide
Everything you need to set up your Arc correctly and build a repeatable stroke — in two to five minutes a day. Read this once, then keep it handy for your first week of practice.
Watch this first
Two minutes of video will save you ten minutes of reading. Start here, then come back for the details.
Four steps to your first practice session
Use this when you have a ball and a hole — on a putting green, a putting mat, or any level stretch of carpet.
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Find a level 5- to 6-foot putt
Set the Arc on the floor, carpet, or green so that a straight line drawn through the two line-up holes points directly at the center of the cup — or at your aim point on a breaking putt. Both line-up holes should sit 3⅜″ off the target line.
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Place your ball at the center line
The back of the ball is always even with the center line of the Arc, and the putter face lines up with that same center line.
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Make a smooth stroke along the rail
Keep the clubface aligned with the lines on top of the Arc, and the heel or toe in light contact with the rail. Do half of your practice strokes in contact and the other half about ½″ away from the rail.
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Use the mirror to check yourself
The adjustable mirror confirms square shoulders and a steady head. Full instructions are in the mirror section below.
Practice five to ten minutes every day
Short and daily beats long and occasional. Thirty to sixty reps a day is enough to make the motion automatic — which is the whole point.
Set the offset for your putter
The 3⅜″ measurement on the diagram is based on a 4″ putter head. If your head is a different length, the offset changes. Add half your putter head length to half the width of the MS-3D (2¾″).
| Putter head length | Offset from the aim point |
|---|---|
| 3½″ | 3⅛″ |
| 4″ | 3⅜″ |
| 4½″ | 3⅝″ |
| 5″ | 3⅞″ |
| 5½″ | 4⅛″ |
The heel and toe drills — no ball, no hole
These are the reps that build the stroke. They work on any level surface, so you can do them at home, in a hotel room, or on a practice green. Two to five minutes, 30 to 60 reps a day.
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Check the face at every line
Set up to the Arc with the putter face lined up with the middle line. Move the putter to each back-stroke alignment line and stop, checking that the face is properly aligned with the line on the Arc. Then make a forward stroke, stopping and checking at each line on the way through. Do this with the heel in contact and again with the toe in contact.
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Repeat with a gap
Run the same sequence again, this time keeping the heel or toe about ½″ away from the rail.
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Find a level spot
A floor, carpet, or putting green all work. Level matters more than surface.
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Set your offset
Place the MS-3D so the two line-up holes point at a spot 3⅜″ from your aim point, as shown in the diagram above. Adjust that number for your putter head using the calculator.
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Smooth strokes in light contact
Make several smooth strokes with the heel — or the toe — in light contact with the rail, keeping the clubface aligned with the lines on top of the Arc.
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Smooth strokes with a gap
Repeat the same strokes with the heel or toe held ½″ to 1″ away from the rail. This step matters: it keeps you from building radial forces into your stroke.
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Make it a daily habit
The goal is a stroke that runs automatically, one you never have to think about. A few minutes every day gets you there faster than an hour once a week.
Never try to swing the putter head in a curve
With a correct setup, the heel or toe of your putter tracks along the face of the Arc on its own, and the putter head releases naturally. That happens because you're making a small, minimal-wrist golf swing on an inclined plane. The putter should never chase "down the line."
Using the adjustable mirror
The mirror is what makes the MS-3D different from a plain arc. Use it to check the two things golfers get wrong most often: a moving head and open or closed shoulders. It clips on when you want feedback and comes off when you'd rather just work on feel.
A quiet head and body
Set the MS-3D up indoors and adjust the mirror so you can see the ceiling from both the heel and toe arcs, without moving your head to find it. Make your practice strokes, alternating between the two arcs. If the ceiling doesn't move, your head and body stayed still. Check this during every daily session.
Shoulder, head, and eye alignment
Take your normal putting stroke setup on either arc, with the putter head square to the target line and lined up exactly with the centerline of the mirror and the Arc. This part is important. Then adjust the mirror to view whatever you want to monitor — shoulders, head position, or eye position. The small notches on the MS-3D let you adjust the mirror fully for both the toe arc and the heel arc.
If you're checking your shoulders, they should look square to the mirror at setup. Make a practice stroke, step away from the Arc, and repeat the setup procedure. Confirm the position looks the same before every practice stroke.
Why an arc, and not straight back and straight through
Ask twenty golfers how the putter should move and most will still say "down the line, straight back and straight through." For that to actually happen, you'd have to swing the putter on a plane that is perfectly vertical to the ground, with a horizontal spinal axis of rotation — or manipulate the putter head with your hands and do it identically every single time. Almost nobody can. Most golfers putt on a plane somewhere between horizontal and vertical, which means their putter path cannot be straight back and straight through.
When you putt straight back and straight through on an inclined plane, the heel and toe both travel along a large elliptical arc when viewed from above. Apollonius of Perga, who lived between 262 BC and 190 BC, was the first to calculate the formulas for that arc, and the Putting Arc was built from them.
Because the Arc is based on an ellipse taken from a very large circle, it fits most golfers from under five feet tall to well over six feet tall, assuming the stance and setup are correct. It's also non-adjustable — so if it works for you today, it will work exactly as well in five years. That makes it a permanent benchmark you can come back to whenever your stroke drifts off track.
The result is a stroke in which the putter head moves on a three-dimensional arc back, slightly upward and inward at the same time, while the face stays square to the putter path rather than the target line. That's what produces square contact and a proper release of the putter head.
The Putting Arc was built from the golf swing and putting concepts of Homer Kelley, Ben Doyle, VJ Trolio, and Mike Shannon; the conic section formulas of Apollonius of Perga; and the applied mathematics of Joey Hamilton.
What the Arc has done at the highest level
- Over 1,400 professional tournament wins since 2002
- One or more wins in every professional major
- Wins in ten different USGA National Championships
- Still holds the all-time 72-hole PGA Tour scoring record of 254
Questions golfers ask about the arc stroke
These four come up constantly, and the answers are simpler than you'd expect.
How far should the putter move inside the target line on the backstroke and through stroke?
The putter moves inside along the arc of the Putting Arc on both the backstroke and the through stroke. If you're set up to the ball correctly, you should be able to simply rotate your shoulders around your spinal pivot point — the T3 vertebra — and the putter will follow the arc fairly closely.
The correct arc is a result of a correct setup and shoulder rotation, not something you're trying to do. It isn't something we invented either. It's a way to replicate what some of the best putters in history — the Ben Crenshaws, Brad Faxons, and Tiger Woodses — have done naturally since they were kids.
Should the putter face stay square to the target line or to the putter path?
The putter face is always square to the arc, and only square to the target line at impact.
What do TV announcers mean when they say a golfer isn't "releasing" the putter head?
Releasing the putter head simply means letting it stay square to the arc, as above. Nothing more complicated than that.
Will the MS-3D fit my putter?
Yes. The Arc accommodates blades, mallets, and long or broomstick putters, and you can use either the heel or the toe against the rail. It's also non-handed, so it works the same for left- and right-handed golfers.
Do I have to use the mirror?
No. Attach it when you want feedback on your setup and head movement, and remove it when you want to focus purely on feel.
Can I take the MS-3D with me?
At 33 inches and about 2.2 pounds it's light, but it isn't pocket-sized — it's built for home practice and pre-round warm-ups. If you want something for the golf bag, the Putting Arc Travel T3 is 21 inches and about 9 ounces, and trains the same stroke.
Give it two minutes a day for a couple of weeks
That's genuinely all it takes to feel the difference, and you're covered by our 60-day money-back guarantee either way. If anything about your setup isn't clear, call or email us — we'd much rather talk it through than have you practice a setup that's slightly off.