The cost-efficient workhorse for general precision automation: hardened raceways, two rows of recirculating steel balls, and a full range of C / L / S carriage lengths on every rail size.
The ST series is the backbone of most compact automation builds. Rails are precision-ground and through-hardened; carriages ride on two rows of recirculating steel balls with controlled preload, so repeatability stays put over millions of cycles.
Every size comes with standard (C), long (L) and — from 7 mm up — short (S) carriage lengths, so you can tune load capacity and envelope independently. And because SMT self-lubricating carriages share the same envelope, you can switch without redesigning the mounting interface.
Controlled preload and ground raceways keep lost motion low over the life of the axis — the spec you read on day one is the spec you get after a few million cycles.
Pick the carriage length to match your load and moment: standard C for general use, long L for higher moments, short S where envelope wins.
Design the mounting once. If a later application turns high-cycle or maintenance-hostile, swap in SMT self-lubricating carriages without touching the layout.
Rails are cut to required length within the manufacturing range — hole positions and end distances confirmed on the order drawing.
ST3 weighs 0.8 g per carriage. Where every gram and millimetre counts — optics, sensors, micro-stages — the small sizes have no rival.
No distribution layer. You buy from the factory that grinds the rails, with engineering support from the people who make them.
Four-direction load capacity and controlled preload help limit elastic deformation. All values are catalog reference data.
| Model | H (mm) | W (mm) | L C/L/S (mm) | Rail W×H | Pitch | C dyn. (kgf) | C₀ stat. (kgf) | MR / MP / MY (kgf·m) |
|---|---|---|---|---|---|---|---|---|
| ST7 / SMT7 | 8 | 17 | 23.5 / 31 / 19 | 7 × 5 | 15 | 100 / 140 / 96 | 127 / 200 / 116 | 0.48–0.78 / 0.18–0.49 / 0.15–0.49 |
| ST9 / SMT9 | 10 | 20 | 30.4 / 40.5 / 21.5 | 9 × 6 | 20 | 190 / 260 / 120 | 260 / 410 / 151 | 1.2–2.0 / 0.3–1.9 / 0.24–1.9 |
| ST12 / SMT12 | 13 | 27 | 34 / 44.4 / 25.4 | 12 × 8 | 25 | 290 / 380 / 225 | 400 / 600 / 243 | 2.6–3.9 / 0.53–3.7 / 0.46–3.7 |
| ST15 / SMT15 | 16 | 32 | 42 / 56.9 / 32 | 15 × 10 | 40 | 470 / 650 / 356 | 570 / 930 / 397 | 4.6–7.5 / 1.2–5.9 / 1.0–5.9 |
| ST20 / SMT20 | 20 | 40 | 50 / 67.7 | 20 × 11 | 60 | 678 / 868 | 926 / 1316 | 9.4–13.4 / 5.4–10.4 / 4.5–8.7 |
Units: dimensions in mm unless stated. C/L/S = standard, long and short carriage variants. 1 N = 0.102 kgf. All values are catalog reference data — use the detailed drawing for mounting design.
| Model | Rail width | Carriage variants | Carriage weight |
|---|---|---|---|
| ST3 / SMT3 | 3 mm | C · L | 0.8 g (C) / 1.2 g (L) |
| ST5 / SMT5 | 5 mm | C · L | 3.5 g (C) / 4.5 g (L) |
Full dimension and load datasheets for the 3 mm and 5 mm series — ask us, we send them within one business day.
Drop-in correspondence to other miniature guide brands, rebuilt from the catalogue. Dashes mean the other brand has no equivalent in that size — not a hidden surcharge.
Swipe the table sideways to see all columns →
| DDJ model | CPC | HIWIN | THK | IKO | Schneeberger | SKF | Schaeffler / INA |
|---|---|---|---|---|---|---|---|
| ST3C | MR3MN | — | — | — | — | — | — |
| ST3L | MR3ML | — | — | — | — | — | — |
| ST5C | MR5MN | MGN5C | — | — | — | — | — |
| ST5L | MR5ML | — | — | — | — | — | — |
| ST7C | MR7MN | MGN7C | RSR7M · RSR7ZM · RSH7M · RSH7ZM | MSC7M | LWL7..B · LWL7 | SEBS7A-(N) | (S)SEB(Z)8 |
| ST7L | MR7ML | MGN7H | RSR7N | MSC7LM | LWLG7..B | — | (S)SELB8 |
| ST9C | MR9MN | MGN9C | RSR9KM · RSR9ZM · RSH9KM · RSH9ZM | MSC9M | LWL9..B · LWL9..BCS · LWL9 | SEB(S)9A-(N) | (S)SEB(Z)10 |
| ST9L | MR9ML | MGN9H | RSR9N | MSC9LM | LWLG9..B | SEB(S)AY-(N) | (S)SELB10 |
| ST12C | MR12MN | MGN12C | RSR12VM · RSR12ZM · RSH12VM · RSH12ZM | MSC12M | LWL12..B · LWL12..BCS · LWL12 · LWL12CS | SEB(S)12A-(N) · SER(S)12A-(N) | (S)SEB(Z)13 |
| ST12L | MR12ML | MGN12H | RSR12N | MSC12LM | LWLG12..B | SEB(S)12A-(N) | (S)SELB13 |
| ST15C | MR15MN | MGN15C | RSR15VM · RSR15ZM · RSH15ZM | MSC15M | LWL15..B · LWL15 · LWL15..S | SEB(S)15A-(N) · SER(S)15A-(N) | (S)SEB(Z)16 |
| ST15L | MR15ML | MGN15H | RSR15N | MSC15LM | LWLG15..B | SEB(S)15AY-(N) | (S)SELB16 |
Replacement guidance: envelope dimensions match; verify hole pattern, preload class and seal option against your drawing before ordering — we check it for you, free.
A good rule: match rail width to the load, then check the permissible moments. ST9 is the most common pick for precision automation; ST5 and ST7 dominate medical, optical and inspection instruments; ST12–ST20 take heavier compact machinery loads.
Yes — standard lengths ship ex-stock. Custom rail lengths and hole patterns are produced in 7 working days. Minimum order is 1 piece, so prototype builds are welcome.
In most sizes, yes — the cross-reference table above shows the correspondence. Envelope matches; we verify hole pattern, preload and seals against your drawing before you order.
Every guide we ship carries a 1-year warranty, backed by factory-direct support.
Send us the model, quantity and stroke length — we reply with a price and lead time within one business day. Standard sizes are ex-stock; custom lengths and hole patterns in 7 working days; 1 piece is enough to start; every guide carries a 1-year warranty.