Grasshopper clock
$8.00 Grasshopper clock
3D
Published 2021-09-06T08:18:48+00:00
Grasshopper Escapement Clock
Link to Instructions and 3D View
Design inspired by John Harrison invention
https://en.wikipedia.org/wiki/John_Harrison
He designed the grasshopper escapement as an attempt to improve the accuracy of clocks
He also took on the challenge of designing a precise marine clock
The design of the escapement is closely similar to the dimensions and angles layed out by John Harrison, the size of the escape wheel is increased to 210 mm to allow for an easy print on a FDM printer
The clock also includes a maintaining power spring to allow rewinding with the clock still beeing powerd by the spring
There is a fine tuning screw at the top of the clock that allows tunning the lenght of the pendulum with the clock running
A set of instruction can be found here:
There is a 3D view of the complete clock included with the files is a XHTML format, the file can be opened in a browser, Chrome, Safari, Edge
Expect to spend a week or two to print all the parts
Clock will run over 24 hours with a 1 meter drop of the weight
It runs with an accuracy well under +/- 1 minute a day
Existing videos:
https://youtu.be/TrXwS0jcLvQ
https://youtu.be/JBG6zJk3xOo
https://youtu.be/r_xHFzkSbGk
Supplies
M3 screws and nuts
bearings 605
rod 5 mm x 100 mm
piano wire 2 mm 30 to 80 mm for shafts
piano wire 1 mm for maintain spring
piano wire 0.5 mm for suspension spring
BB still ball to load the bob
10 mm dowell for the pendulum rod
3 to 4 Kg weight to power the clock
All Parts are printed in PLA + with 0.2 mm layer and 0.4 mm nozle , usually with 4 outer walls, 4 layer top and bottom, 20% infill
The second Indicator has been a chalenge, I ended up adding outer walls until it filled up
I find it best to print the gears one at the time, to limit stringing, also pay attention to the first layer and limit the elephatnt foot
I use Cura and there is a setting in Walls called: Initial layer horizontal expansion. I use a negative value of 0.25 to 0.35 mm to prevent the issue
Warning: too big of a value can cause bed adhesion issue!
| Date published | 06/09/2021 |
| Price | $8.00 |
| Material Quantity | 1Kg |
| Dimensions | 210 x 210 bed needed |
| Support Free | YES |
Quelle belle horloge à échappement sauterelle ! Bravo Jacques !