# Ball screw nuts SFU1204, SFU1605, SFU1610, SFU2005: flange diameter, bolt circle, hole size, flats and length (SFU2010 length)

> What are the dimensions of an SFU1605 ball screw nut: flange diameter, bolt circle, mounting holes, length and barrel diameter, and the same for SFU1204, SFU1610 and SFU2005?

- Category: Hardware › Bearings, rails & motion
- Kind: Standard part
- Basis: Sorotec's ball spindle data sheet and Albeco's DIN 69051 SU table agree on every column for 1605, 1610 and 2005; SFU1204 from Sorotec with Matara as a partial check; McMaster-Carr linked for CAD
- Page: https://xemstudio.com/objects/ball-screw-nuts-sfu/ · JSON: https://xemstudio.com/api/geometry?object=ball-screw-nuts-sfu · Plain text: https://xemstudio.com/objects/ball-screw-nuts-sfu/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
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**Exact dimensions.** True size, with no tolerance added.

## Notes

- SFU is the rolled-ball-screw flanged nut sold for CNC routers, mills and 3D printers: SFU1605 = 16 mm screw, 5 mm lead; SFU1204 = 12 mm, 4 mm; SFU1610 = 16 mm, 10 mm lead; SFU2005 = 20 mm, 5 mm. The flange has two flats (cut across the flange at the width given) and holes on the bolt circle; the barrel (Ø D) is the part that goes through the nut-housing or plate bore. The nut housings sold with the kits take the barrel; BK / BF end supports take the screw ends (HIWIN pairing, next page).
- Numbers: Sorotec's data sheet (columns BN, FN, LN, DN1, DN2, DN3, TN, d1) and Albeco's DIN 69051 SU single-flange table (D, A, B, L, W, H, Q) agree on every column for SFU1605, SFU1610 (length 57 in both) and SFU2005. SFU1204 is from Sorotec alone for the flange (Ø42, bolt circle 32, hole 4.5, thickness 8, flats 30, barrel 24); Matara's 12 × 4 flanged nut gives width 30 and height 32, which match the flats and bolt circle, but a length of 40 against Sorotec's 35. Both are real nuts (35 is the 3-turn SFU1204, 40 the 4-turn nut) but the sources do not say which, so the table shows 35 and the page warns about 40.
- Disagreements and gaps: the hole count is not stated by Sorotec or Albeco. ASE Bearings calls the SFU2005 a '4-hole flange' (OD 36, length 51, flange about 58); a ball-screw-kit data sheet (Handsontec) draws a different 1605 nut (flange Ø42, barrel Ø22, flats 34, length 36) with 6 holes for M4. Because of that no flange-with-holes file is drawn. The lube-port thread (M5 / M6) is Sorotec's TN column; the nut of the SFU2010 is listed with only its length (60).
- McMaster-Carr's ball nut and miniature ball screw categories are linked as the per-part CAD source; none of their numbers are mixed into the SFU table.
- Files: none. The tables give the nut's flange and barrel numbers but not its hole count or the shape of the flats beyond the width across, so a hole plate would be guessed.
- Left out: SFU2505, 3204, 3205 and larger (Albeco has DIN 69051 rows for them but no SFU-named table was read), SFN / SFNU and DFU double nuts, ball-screw root and ball diameters, preload and load ratings.

## Sizes

| nut | screw Ø, mm | lead, mm | flange Ø, mm | flange thickness, mm | nut length L, mm | bolt circle (hole spacing), mm | mounting hole, mm | flats (across), mm | barrel Ø D, mm | lube thread | end supports (HIWIN naming) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| SFU1204 | 12 | 4 | Ø42 | 8 | 35 | Ø32 | Ø4.5 | 30 | Ø24 | M5 (Sorotec) | BK10 / BF10 |
| SFU1605 | 16 | 5 | Ø48 | 10 | 50 | Ø38 | Ø5.5 | 40 | Ø28 | M6 | BK12 / BF12 |
| SFU1610 | 16 | 10 | — | — | 57 | — | — | — | — | — | BK12 / BF12 |
| SFU2005 | 20 | 5 | Ø58 | 10 | 51 | Ø47 | Ø6.6 | 44 | Ø36 | M6 | BK15 / BF15 |
| SFU2010 | 20 | 10 | — | — | 60 | — | — | — | — | — | BK15 / BF15 |

## Where the files are

- Sorotec: [Datasheet ball screws: SFU nut BN, FN, LN, DN1-DN3, TN, d1 for 1204 / 1605 / 1610 / 2005 / 2010 and the BK / FK pairing](https://www.upload.sorotec.de/doku/manuals/Datasheet_Ball_Spindles_en_Soro.pdf) — web — Publisher's page; dimensions are facts
- Albeco: [SU single-flange ball nuts (DIN 69051): D, A, B, L, W, H, Q for 01604 to 08020](https://www.albeco.com.pl/data/catalogueb/su.pdf) — web — Publisher's page; dimensions are facts
- Matara: [Precision flanged ball-screw nuts (SFU / SFNU series): width, length, height, pitch](https://www.matara.com/products/linear-motion/ballscrews-and-end-supports/rolled-ballscrews/ballnuts/) — web — Publisher's page; dimensions are facts
- ASE Bearings: [SFU 2005-4 standard ball nut: nut OD 36, length 51, flange about 58, 4-hole flange](https://asebearings.com/?p=5017) — web — Publisher's page; dimensions are facts
- Handsontec: [Ball screw kit 1605 data sheet: flange Ø42, barrel Ø22, flats 34, length 36 and 6 holes (a different nut from SFU1605; shown as a disagreement)](https://www.handsontec.com/dataspecs/linear%20motion/Ball%20Screw-Kit-1605.pdf) — web — Publisher's page; dimensions are facts
- McMaster-Carr: [Ball nuts (free STEP/IGES per part, for your own design use; no redistribution)](https://www.mcmaster.com/products/ball-nuts/) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution (verify at link)
- McMaster-Carr: [Miniature ball screws (free STEP/IGES per part, for your own design use; no redistribution)](https://www.mcmaster.com/miniature-ball-screws) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution (verify at link)

## Questions

**What are the dimensions of an SFU1605 nut?**

16 mm screw, 5 mm lead; flange Ø48 × 10 thick, bolt circle Ø38, Ø5.5 holes, flats 40 apart, barrel Ø28, length 50.

**What is the bolt circle of an SFU2005?**

Ø47 with Ø6.6 holes; flange Ø58 × 10, flats 44, barrel Ø36, length 51.

**How long is an SFU1610?**

57 mm (same flange as the SFU1605: Ø48, bolt circle 38).

**Which end supports go with an SFU1605?**

BK12 on the fixed end and BF12 on the supported end (the same pair fits an SFU1610); SFU1204 uses BK10 / BF10 and SFU2005 BK15 / BF15.

## Fits with

- [Ball screw end supports BK10, BK12, BK15, BF10, BF12, BF15, FK, FF: bore, bearing, base hole spacing, height (HIWIN tables)](https://xemstudio.com/objects/ball-screw-end-supports-bk-bf-fk-ff/)
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