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Linear ball bushings LM..UU and LM..LUU (LM8UU, LM10UU, LM12UU, LM16UU, LM20UU, long LUU): bore, OD, length, ring-groove numbers

What are the dimensions of LM8UU, LM10UU, LM12UU, LM16UU, LM20UU and the long LM8LUU, LM10LUU, LM12LUU linear bearings: bore, OD, length and snap-ring groove? · Standard part · basis: A Japanese-standard catalogue (DriveHQ) for d, D, L, B, W, D1, checked against WF International, Samick, Tuli, THK and McMaster; disagreements listed; McMaster-Carr linked for CAD

Also called: lm8uu dimensions, lm10uu dimensions, lm12uu dimensions, lm16uu dimensions, lm20uu dimensions, lm8luu dimensions, lm10luu, lm12luu, lm16luu, lm20luu, lm8uu ring groove, lm8uu snap ring groove, linear bearing 8mm groove diameter, lm8uu 8x15x24, lm10uu 10x19x29, lm12uu 12x21x30, lm6uu dimensions, lm13uu

Exact dimensions. True size, with no tolerance added.

sizes: 30 in table

Notes

The LM..UU linear ball bushing (linear bearing, ball bushing, 'LM8UU') is the cylindrical bushing on every 3D printer smooth rod and many CNC axes: the bore d is the shaft diameter, D the outside diameter, UU means a wiper seal at each end, L (long) doubles the ball set (LM8LUU is 45 long against 24). Two snap-ring grooves in the OD, groove width W and groove diameter D1, hold it in a housing with circlips.
Numbers: the DriveHQ catalogue (maker not named, Japanese-standard dimensions) for d, D, L, B, W, D1. For LM8 to LM60, D and L equal the flanged LMF bodies on the flanged-bushing page (Samick, Tuli, THK, McMaster); for LM..LUU the DriveHQ table, WF International (L, W, D1) and a Misumi catalogue page (L, B, W, D1) agree on every row except L at 40 and 60 mm (see below), and Samick's LMF..L agrees on L. LM3UU and LM4UU come from CWL Bearing (d, D, L only).
B is shown as printed and not defined in the sources' text (it is a dimension between the two grooves in the drawing). Misumi's own C-LMU series prints different B values (15.3 for the 8 mm bushing against 17.5 here), so B is catalogue-specific; because of that the grooves are not drawn in any file. The groove width W and groove diameter D1 are the same in every catalogue read where they could be matched (1.1 and 14.3 for LM8; 1.3 and 18 for LM10).
Disagreements: LM40LUU is 154 (DriveHQ, WF International, Samick) against 151 (the Misumi catalogue page, Tuli LMK40LUU) and LM60LUU 211 against 209 (also McMaster's 60 mm flanged part). CWL Bearing prints LM6UU as 17 long and LM8SUU as 19; the DriveHQ, Samick and THK tables say LM6UU is 19 and LM8SUU is 17, so CWL's two rows are not used.
Files: none on this page (a plain bushing with the grooves in unknown positions would be invented geometry). The flanged-bushing page has 20 solids built from the same d, D, L; for a plain press-in bushing use the bore d and OD D here. The existing LM8UU / 8 mm rod page has the 8 mm case.
Left out: LM..UU above 60 mm, load ratings and tolerance grades (THK's housing bore tolerance table is H7 / J7 / H6 / J6 / K6 and its shaft table f6 / g6 / h6 / f5 / g5 / h5 / h7 / k6, mentioned in the mating table, not tabulated by size).

Linear ball bushings LM..UU and LM..LUU (LM8UU, LM10UU, LM12UU… size chart

designation	bore d (shaft Ø), mm	OD D, mm	length L, mm	B (as printed), mm	ring-groove width W, mm	ring-groove Ø D1, mm
LM3UU	3	7	10	—	—	—
LM4UU	4	8	12	—	—	—
LM5UU	5	10	15	10.2	1.1	9.6
LM6UU	6	12	19	13.5	1.1	11.5
LM8SUU	8	15	17	11.5	1.1	14.3
LM8UU	8	15	24	17.5	1.1	14.3
LM10UU	10	19	29	22	1.3	18
LM12UU	12	21	30	23	1.3	20
LM13UU	13	23	32	23	1.3	22
LM16UU	16	28	37	26.5	1.6	27
LM20UU	20	32	42	30.5	1.6	30.5
LM25UU	25	40	59	41	1.85	38
LM30UU	30	45	64	44.5	1.85	43
LM35UU	35	52	70	49.5	2.1	49
LM40UU	40	60	80	60.5	2.1	57
LM50UU	50	80	100	74	2.6	76.5
LM60UU	60	90	110	85	3.15	86.5
LM6LUU (long)	6	12	35	27	1.1	11.5
LM8LUU (long)	8	15	45	35	1.1	14.3
LM10LUU (long)	10	19	55	44	1.3	18
LM12LUU (long)	12	21	57	46	1.3	20
LM13LUU (long)	13	23	61	46	1.3	22
LM16LUU (long)	16	28	70	53	1.6	27
LM20LUU (long)	20	32	80	61	1.6	30.5
LM25LUU (long)	25	40	112	82	1.85	38
LM30LUU (long)	30	45	123	89	1.85	43
LM35LUU (long)	35	52	135	99	2.1	49
LM40LUU (long)	40	60	154	121	2.1	57
LM50LUU (long)	50	80	192	148	2.6	76.5
LM60LUU (long)	60	90	211	170	3.15	86.5

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Linear motion catalogue (maker not named; hosted on DriveHQ)	Ball bushes: LM..UU and LM..LUU (d, D, L, B, W, D1), LMF (d, D, L, D1, H, PCD, hole), LMK / LMH (K, W, A, F)	web	Publisher's page; dimensions are facts
WF International	LM..LUU long linear bearing: d, D, L, ring-groove numbers	web	Publisher's page; dimensions are facts
Misumi catalogue (India site, page 18)	LM..LUU long standard bushings: dr, D, L, B, W, D1 (L is 151 / 209 for LM40LUU / LM60LUU there)	web	Publisher's page; dimensions are facts
CWL Bearing	LM..UU linear motion bearings: d, D, L for LM3UU to LM60UU	web	Publisher's page; dimensions are facts
Misumi	C-LMU linear bushing (Misumi's own B, W, D1 differ from the LM..UU catalogues; used only to show the spread)	web	Publisher's page; dimensions are facts
Samick (via AIMS Industrial)	Flanged linear bushing LMF, Asian standard catalogue p.70-71: d, D, L, D1, H, PCD, d1 x d2 x h	web	Publisher's page; dimensions are facts
Samick (via AIMS Industrial)	Flanged long linear bushing LMF..L, Asian standard catalogue p.72-73: d, D, L, D1, H, PCD, d1 x d2 x h	web	Publisher's page; dimensions are facts
Tuli (distributor datasheet)	LMK..UU square flange linear bearings: d, D, L, flange square K, H, PCD, bolt hole d1 x d2 x h	web	Publisher's page; dimensions are facts
THK	Linear bushings LM, LME, LMF: housing bore tolerances H7 / J7 / H6 / J6 / K6 and LM shaft tolerances f6 / g6 / h6 / f5 / g5 / h5 / h7 / k6 (B4-39 to B4-41)	web	Publisher's page; dimensions are facts
McMaster-Carr	Linear ball bearings and linear bearing shafts (rods) (free STEP/IGES per part, for your own design use; no redistribution)	STEP, IGES, PDF	McMaster-Carr site terms: personal design use, no redistribution verify
McMaster-Carr	Flange-mounted linear ball bearings (round and square flange, inch and metric) (free STEP/IGES per part, for your own design use; no redistribution)	STEP, IGES, PDF	McMaster-Carr site terms: personal design use, no redistribution verify

Xem scan

File coming

No downloadable true-size file yet: the published figures do not fix the whole shape, and Xem never guesses a number. A measured scan is planned; request it and it moves up.

Let your AI pull this. Add https://xemstudio.com/mcp to Claude, ChatGPT, Cursor or any MCP client (free, no account, one minute) and it can look up exact sizes, mating fits and free STEP/STL from every chat.

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Plain text: sheet.txt · JSON: /api/geometry?object=linear-ball-bushings-lm-uu-luu

Schematic, not to scale.