The series, sizes and blocks shown here are normally stocked and ship right away, cut to your length. Airtac builds further sizes, block styles and joint rails beyond 4 m to order on a longer lead time.
Need something that isn't listed? Tell us what you're building and we'll come back with availability, lead time and pricing.
Sections drawn to scale from the Airtac catalog dimensions.
Airtac profile linear guide rails, cut to length
We supply Airtac LSH and LSD profile linear guide rails cut to any length from 4 m stock, together with the matching flange and square carriage blocks. You are not restricted to fixed stock lengths: specify the length your machine needs and the rail is machined to it, with the mounting hole pattern set out to Airtac's published edge-pitch limits. Sizes 15 to 45 mm, normally stocked and cut to order.
Rails cut to your length
Profile linear rail is normally sold in fixed stock lengths — commonly 400, 580, 760 and 1000 mm — which means designing a machine around whatever the catalog happens to offer, or shortening rail yourself. We cut from 4 m stock to the length you actually need, to the millimetre, and the price follows the length rather than rounding up to the next size.
Shortening hardened rail is not a bench job. Profile rail of this type is through-hardened, typically to around HRC 58–64, so it needs abrasive or carbide cutting rather than a bandsaw. More awkwardly, the mounting holes are counterbored at a fixed pitch during manufacture. Cut a rail down yourself and the last hole ends up wherever the cut leaves it — if that edge distance is too small the counterbore breaks through the end face and the rail is scrap, and if it is too large the end of the rail is unsupported. Airtac publishes a permitted range per size for precisely this reason.
Enter a length in the calculator above and the hole count and both edge distances are worked out for you, checked against Airtac's limits for that rail, and written into the part number. A configuration that cannot be made is refused rather than quoted.
What lengths can you supply?
Any length up to the single-rail maximum — 4040 mm on sizes 15 to 25, 4030 mm on 30 and 35, 4020 mm on 45. Common requirements such as 500 mm, 750 mm, 1000 mm, 1200 mm, 1500 mm and 2000 mm are quoted exactly like anything in between; there is no premium for an unusual figure. Runs longer than a single rail are supplied as joint rails, matched so the hole pattern stays continuous across the join.
Can I just cut a standard-length rail myself?
You can, with the right equipment, but you inherit the hole-pattern problem above and the cut end will not be square or deburred without further work. Buying the finished length removes both, and the rail arrives ready to bolt down.
LSH or LSD — which series
Both are four-row, 45° contact profile rails with the same mounting principle, and both are dimensionally interchangeable with the common industry profile. The difference is height and capacity.
| Series | Type | Sizes | Assembly height | Dynamic load, size 20 |
|---|---|---|---|---|
| LSH | Standard | 15, 20, 25, 30, 35, 45 mm | Taller — LSH20 rail is 17.5 mm | 18.6 kN |
| LSD | Low profile | 15, 20, 25 mm | 2 mm lower — LSD20 rail is 15.5 mm | 12.1 kN |
Choose LSD where build height is constrained and loads are moderate. Choose LSH for higher load and moment capacity, or for sizes above 25 mm, which LSD does not cover. A block only fits a rail of the same series and size — an LSD20 block will not mount on an LSH20 rail, because the profiles differ.
Rail specification
Mounting holes are spaced at pitch P, with the first and last hole set in from each end by the edge pitch S and E. Overall length is L = (n−1) × P + S + E, where n is the number of holes.
| Rail | Pitch P | Standard edge pitch | Edge pitch range | Max single length | Section W×H | Weight |
|---|---|---|---|---|---|---|
| LSH15 | 60 mm | 40 mm | 5–55 mm | 4040 mm | 15 × 15 mm | 1.43 kg/m |
| LSH20 | 60 mm | 40 mm | 6–54 mm | 4040 mm | 20 × 17.5 mm | 2.23 kg/m |
| LSH25 | 60 mm | 40 mm | 7–53 mm | 4040 mm | 23 × 22 mm | 3.32 kg/m |
| LSH30 | 80 mm | 55 mm | 8–72 mm | 4030 mm | 28 × 26 mm | 4.5 kg/m |
| LSH35 | 80 mm | 55 mm | 8–72 mm | 4030 mm | 34 × 29 mm | 6.37 kg/m |
| LSH45 | 105 mm | 67.5 mm | 11–94 mm | 4020 mm | 45 × 38 mm | 10.7 kg/m |
| LSD15 | 60 mm | 40 mm | 5–55 mm | 4040 mm | 15 × 12.5 mm | 1.23 kg/m |
| LSD20 | 60 mm | 40 mm | 6–54 mm | 4040 mm | 20 × 15.5 mm | 2.11 kg/m |
| LSD25 | 60 mm | 40 mm | 7–53 mm | 4040 mm | 23 × 18 mm | 2.76 kg/m |
Stock rail part numbers follow the pattern
LSH20RLX4000-N-D — series, size, 4000 mm stock length, normal accuracy,
standard clearance. A cut rail is identified by its finished length and the edge pitches
it was machined to.
Carriage blocks
Flange blocks (-F3N-) are wider and lower, bolting from above or below
through a universal mount. Square blocks (-HN-) are narrower and taller,
bolting from above. Both carry the same load rating for a given size; the choice is
about mounting geometry and available width.
| Block | Form | Dynamic C | Static C₀ | Assembly height | Width |
|---|---|---|---|---|---|
LSH15BK-F3N-N-D-M4 | Flange | 11.3 kN | 17.9 kN | 24 mm | 47 mm |
LSH15BK-HN-N-D-M4 | Square | 11.3 kN | 17.9 kN | 28 mm | 34 mm |
LSH20BK-F3N-N-D-M6 | Flange | 18.6 kN | 28.6 kN | 30 mm | 63 mm |
LSH25BK-F3N-N-D-M6 | Flange | 26.9 kN | 39.4 kN | 36 mm | 70 mm |
LSH35BK-F3N-N-D-M6 | Flange | 50.8 kN | 72.3 kN | 48 mm | 100 mm |
LSH45BK-F3N-N-D-P01 | Flange | 80.7 kN | 110.3 kN | 60 mm | 120 mm |
LSD20BK-F3N-N-D-M6 | Flange | 12.1 kN | 22.4 kN | 28 mm | 59 mm |
LSD25BK-F3N-N-D-M6 | Flange | 19.3 kN | 34.7 kN | 33 mm | 73 mm |
Use the configurator above for the full range, including every size and both block forms, with dimensioned cross-section and top-view drawings.
Full Airtac catalogs
The figures on this page are taken from Airtac's own catalogs. For accuracy classes, preload options, dust-proofing, lubrication and installation guidance, go to the source:
- LSH Series — Standard Linear Guide PDF · airtac.com
- LSD Series — Low Profile Linear Guide PDF · airtac.com
Common questions
What if I need a rail longer than 4 metres?
Longer runs use joint rails, supplied as matched sections that butt together end to end with a continuous hole pattern. Send us the total length and we will quote it.
What are S and E, and why do they matter?
S and E are the distances from each end of the rail to the first and last mounting hole. Airtac sets a permitted range per size — too small and the bolt hole breaks through the end face, too large and the rail end is unsupported. The configurator blocks any combination outside that range rather than quoting a rail that cannot be made.
Will these fit in place of my current rails?
The LSH series shares its mounting dimensions with the widely used HG profile — the same assembly height, block width, bolt pattern, rail section and mounting-hole pitch at every size from 15 to 45 mm — so it fits designs built around that standard, including Hiwin HGH and equivalents from THK, NSK and others.
The hole pattern matches too. HG rails are normally supplied with the first and last mounting holes 20 mm from each end, and that is how we cut ours as standard — so a replacement rail lands on the holes already in your machine. No re-drilling, and nothing to specify. If your existing rail uses different end distances, enter them in the S and E fields above and we will cut to match.
Load ratings differ between manufacturers even where dimensions are identical, so check the rating shown here against your application before switching.
How quickly do orders ship?
Sizes and blocks listed here are normally stocked and ship promptly once cut. Other sizes, block styles and joint rails are available on a longer lead time — send an enquiry from the configurator and we will confirm availability.