Xem Studiomeasured geometry

Library › Hardware › Stirling & thermoacoustic ·

Built-up crank webs for Ø8 shafts and Ø6 crank pins (two-throw cranks at 90°)

How do I build a two-throw crankshaft with ball-bearing con-rods? · Hardware · basis: Design values; Ø6 dowel crank pins (ISO 8734)

Long Earth Society build part. The cranks of my performance engines. The engines

Exact dimensions. Every file is drawn at true size with no printing tolerance. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your printer's or process's clearance before making the part. Mating features

sizes
7 in table

Notes

  • Discs pressed on Ø8 shafts with Ø6 dowel crank pins pressed through them: the horizontal gamma's crank has four webs (two throws, 76.2 mm apart, a shaft between) and the beta's has two webs and a link web between the two con-rods (the shaft does not pass the con-rods).
  • Pin radius 15 for the displacer (30 stroke) and 18 for the piston (36 stroke); the pins are a quarter turn apart, the displacer leading.

Sizes

partthicknesspin radius
crank-web-56x10-r151015
crank-web-56x11-r151115
crank-web-56x11-r181118
crank-web-56x10-r181018
crank-web-56x8-r18818
crank-web-56x8-r15815
link-web-14-r18-r15-901418 / 15

Mating features

Drawn at the exact size. Open press, slide, run and socket features by your process's clearance; leave designed gaps and clamp fits as drawn.

featureexactmates withfitfiles
shaft holeØ8Ø8 crank shaftpresscrank-web*
pin holesØ6Ø6 dowel crank pinspressall

Where the files are

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

Long Earth SocietyEngine buildsweb, videoLES site

Free files

★ Free files 8 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

crank-web-56x10-r15crank web Ø56 × 10: Ø8 shaft hole, Ø6 pin hole at r 15 (both press), two Ø11 lightening holes beside the pin (counterweight)STEP · STL
crank-web-56x11-r15crank web Ø56 × 11: Ø8 shaft hole, Ø6 pin hole at r 15 (both press), two Ø11 lightening holes beside the pin (counterweight)STEP · STL
crank-web-56x11-r18crank web Ø56 × 11: Ø8 shaft hole, Ø6 pin hole at r 18 (both press), two Ø11 lightening holes beside the pin (counterweight)STEP · STL
crank-web-56x10-r18crank web Ø56 × 10: Ø8 shaft hole, Ø6 pin hole at r 18 (both press), two Ø11 lightening holes beside the pin (counterweight)STEP · STL
crank-web-56x8-r18crank web Ø56 × 8: Ø8 shaft hole, Ø6 pin hole at r 18 (both press), two Ø11 lightening holes beside the pin (counterweight)STEP · STL
crank-web-56x8-r15crank web Ø56 × 8: Ø8 shaft hole, Ø6 pin hole at r 15 (both press), two Ø11 lightening holes beside the pin (counterweight)STEP · STL
crank-web-56x12-r15crank web Ø56 × 12: Ø8 shaft hole, Ø6 pin hole at r 15 (both press), two Ø11 lightening holes beside the pin (counterweight)STEP · STL
link-web-14-r18-r15-90link web 14 thick: Ø6 press holes for the piston pin (r 18) and the displacer pin (r 15, 90° on)STEP · STL

Plain text: sheet.txt · JSON: /api/geometry?object=stirling-built-up-crank-webs

Built-up crank webs for Ø8 shafts and Ø6 crank pins (two-throw cranks at 90°), isometric render of a generated part
Render of crank-web-56x8-r18 from the free STEP; not to scale.

How it fits

In these build lists

Tri-clamp horizontal gamma generator, 2 in,…The classic desk Stirling generator in tri-clamp, built for power: a horizontal …Tri-clamp walking-beam gamma generator, 2 in,…The classic desk walking-beam Stirling in tri-clamp: a standard 2 in tee with th…Tri-clamp charged beta, 2 inA standing beta that holds a charge: the same hot spool, liner, regenerator and …Tri-clamp twin walking-beam gamma generator, 2…Two walking-beam tee units side by side on one crank, a quarter turn apart: each…

You might also need

Con-rods and links with a 626 big end and a 625 small end: 55 to 488 mm, isometric render of a generated part
Con-rods and links with a 626 big end and a 625 small end: 55 to 488 mm5 sizes★ 5 files
Ground rods, hollow piston rod and crank shafts for the performance engines (Ø6, Ø8, Ø10 / 7), isometric render of a generated part
Ground rods, hollow piston rod and crank shafts for the performance engines (Ø6, Ø8, Ø10 / 7)9 sizes★ 13 files
Build list: Tri-clamp horizontal gamma generator, 2 in, chargeable, isometric render of a generated part
Tri-clamp horizontal gamma generator, 2 in, chargeable65 linesassembled
Build list: Tri-clamp charged beta, 2 in, isometric render of a generated part
Tri-clamp charged beta, 2 in59 linesassembled

Questions

Which way does it turn?

The way that brings the displacer pin to each point a quarter turn before the piston pin.