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Oblong endless rack, module 1: two 4π racks joined by 20-tooth half-gear ends
What is a mangle rack? · Modern device · basis: Xem Studio design following Brown's figure (1868); true size, no printing allowance
Also called: mangle rack, endless rack, oblong rack, reciprocating rack loop, cremallera sin fin oblonga, Mangelzahnstange (oblong)
Exact dimensions. True size, with no printing tolerance added.
- length
- 34.56 mm
- width
- 22.0 mm
- height
- 8.0 mm
Notes
- Closed toothed outline: two straight module 1 racks 12.57 mm long (4 pitches) joined by the two halves of a 20-tooth gear, so a pinion can roll right round it; 8 mm thick, Ø3.4 centre hole. Tooth pitch is continuous (π mm on the straights, 18° on the ends) because the end radius is the gear's pitch radius, 10 mm.
- The pinion's centre runs on the parallel curve 10 mm outside the pitch line; at each end the pinion changes sides, so the rack's direction reverses while the pinion keeps turning the same way.
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).
Oblong endless rack, module 1: two 4π racks joined by 20-tooth… size chart
| dimension | value |
|---|---|
| module | 1 |
| straights | 12.57 mm (4 pitches) |
| end radius (pitch) | 10 mm |
| teeth on each end | 10 |
| thickness | 8 mm |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| Henry T. Brown (1868, public domain) | Five Hundred and Seven Mechanical Movements — scan on archive.org | web | Publisher's page; dimensions are facts |
| 507movements.com | Brown's movement No. 119: figure, his text and an animation | web | Publisher's page; dimensions are facts |
| Xem Studio | drawing | web | Publisher's page; dimensions are facts |
Free files
★ Free files 1 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json
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.Plain text: sheet.txt · JSON: /api/geometry?object=oblong-endless-rack-m1-20t-ends
Fits with
Questions
What is a mangle rack?
Closed toothed outline: two straight module 1 racks 12.57 mm long (4 pitches) joined by the two halves of a 20-tooth gear, so a pinion can roll right round it; 8 mm thick, Ø3.4 centre hole. Tooth pitch is continuous (π mm on the straights, 18° on the ends) because the end radius is the gear's pitch radius, 10 mm.