Sightline Rings: Seven-Ring Alignment Sculpture

Seven thin colour-graded rings that nest into a perfect bullseye from one spot and fan out into a staggered rainbow as you walk away from it.

Date: 2026-11-13 Category: Art and Decor Modeling difficulty: Beginner Estimated print: ~7.4 h total · ~84 g PLA (estimate) Suggested price: $35–$55 printed · $5 digital file (estimate) Status: Concept

Description

Sightline Rings is a shelf sculpture that changes with where you stand. Seven flat rings of growing size stand on slim stems along a 200 mm base. Their centres lie on one tilted line. From the end of that line they stack as concentric circles. From anywhere else they slide apart into a fan.

The line descends 15 degrees. That matches a viewer with eyes about 400 mm above a shelf and 1.5 m away, which is a normal cabinet top seen from a standing position. The ring sizes are corrected slightly for distance, so the bands look evenly spaced from that spot.

The rings are 4 mm thick with 5 mm bands, printed flat in a graded palette from cobalt to coral. The base is white.

Why it sells

Art idea: the evidence is inspiration. Anamorphosis is the family of works that resolve only from a viewpoint, and sculpture is one of its forms (Wikipedia). Markus Raetz made sculptures that read as different words from different angles (Wikipedia). The ring spacing uses forced perspective (Wikipedia). I did not gather sales numbers. The gap: anamorphic sculpture usually needs a mirror or a gallery. This one needs a shelf and the right angle.

Who buys it

People who like optical art, colour and geometry: design fans, teachers, gift buyers, office desks. A conversation piece for a hallway cabinet or bookcase. Sold on Etsy and at design markets.

Design overview

• Seven rings with outer radii 14.0 to 62.3 mm, each 5 mm wide and 4 mm thick.
• Ring centres on a line descending 15 degrees at 28 mm spacing.
• Ring sizes corrected for a 1500 mm viewing distance.
• Stems of 8 × 6 mm push into slots in a 200 mm base.
• Seven colours graded cobalt to coral.
• What sets it apart: one viewpoint turns it into a bullseye, every other makes it a rainbow fan.

Dimensions

Parts list

Hardware and non-printed parts

None — fully printed.

Fits and tolerances

• Peg in slot: press, 0.15 mm per side (peg 8 × 6, slot 8.3 × 6.3). Add a dot of glue if you will move it often.
• Ring thickness 4 and stem thickness 6: the stem is thicker so the ring does not wobble toward the viewer.

Modeling guide

Origin: bottom face of the base under ring 1's stem. +X away from the viewer, +Y sideways, +Z up.

1. Base. Sketch 200 × 50 with 4 mm corners from X=-16 to X=184 on XY, extrude 10, fillet the top edge 1.5.
2. Cut seven slots 6.3 (X) × 8.3 (Y) × 7 deep at X = 0, 28, 56, 84, 112, 140, 168, Y=0.
3. Ring i. On the YZ plane sketch the outer circle (radius from the table) and an inner circle 5 smaller, centred on the origin. Extrude 4 symmetric.
4. Stem. Sketch a rectangle 8 wide from the ring's bottom point straight down by (centre height minus radius) plus 6 mm for the peg. Extrude 6 symmetric. Merge with the ring.
5. Repeat for the seven radii. Check that no stem touches a neighbouring ring: all stems sit at their own X.
6. Ring centre height above the base top is 120 − 7.5 × (i − 1). Radius is the corrected value from the table.

Print settings

Assembly

1. Press ring 1 into the slot at the near end. Add rings 2 to 7 in order.
2. Glue a dot on each peg if you want a fixed set.
3. Put the sculpture on a shelf with the long axis pointing at your usual standing spot.
4. Move your head until the rings nest. Adjust the base angle if needed.

Variants and upsells

• A desk version at 60% scale for 600 mm viewing distance.
• Other angles: 0 degrees for eye-level shelves, 25 degrees for low shelves.
• Four-colour and mono sets.
• A series: nine-ring and eleven-ring pieces that continue the palette.

Selling and distribution

Sell printed pieces on Etsy; sell the file on Printables or MakerWorld with the angle as a variable. Price on 84 g of PLA, 7.4 h of machine time and margin. Because the effect depends on shelf height, offer a custom angle. Keywords: optical illusion sculpture, anamorphic art, rainbow ring sculpture, modern shelf decor, geometric desk art, colourful 3D printed art, perspective sculpture, bullseye art, kinetic-looking decor, cabinet decor.

Risks and IP notes

• The effect depends on viewing angle. Mitigation: ship with the 15 degree default and sell a custom-angle option.
• Tall thin stems can bend. Mitigation: stems are 6 mm thick; keep rings in PLA, not TPU.
• Ring 7 is wide for a 50 mm base. Mitigation: the layout is symmetric; use a 70 mm base on a windy or busy shelf.
• Saturation: nested ring art exists, but angle-aligned rings sold with a viewing guide are rare.
• IP: no brand or artist names in the listing; the cited works are inspiration only.

Resource links

• Anamorphosis — viewpoint-dependent images and sculpture
• Markus Raetz — sculptures that change with angle
• Forced perspective — scaling by distance for one viewpoint
• Rock balancing — precarious-looking sculpture as an art practice