GT2, GT3 and GT5 Timing Gear Creator

[eaguirre]

A lot of work for script indeed...

But what you can do is to run the script and create two pulleys:
- First pulley (document GT2) 50 teeth, shaft 5mm with base
- Second pulley (document GT21) 32 teeth, shaft 5mm with base
- In document GT21 select the Gear object from the tree-view
- Then Ctrl+C for copy
- Go to document GT2
- Select the GT2 document from the treeview and do a Ctrl+P
- Then You will end with a Gear001 object.
- Select this object and right click the mouse to show the menu
- Select transform
- Move it upwards (Z axis) 6mm (or the height of your other pulley)
- Then select both Gear and Gear001 objects, go to Part Module and do a Fusion
- That's it!

You will end with something like:

2019-04-26_15-29.png (98.61 KiB) Viewed 3907 times

Go to top of the page and take the latest version of the code 1.2
I added the top and bottom and you can change the height and size of them.

Thank you so much!


Could it be possible to get an option to select a 2 stages pulley? I could be very useful to modelise 3D printed driven pulley for reducer.
I though about this script: it could be great if it could be possible to select pulley, or gears, by mixing the gear WB features maybe?
I assume it's a hard work...
Anyway, thank you again.

[-alex-]

- That's it!

Thanks a lot for this workflow, now I have to try all of this

[DeepSOIC]

How about including it into FCGear add-on workbench?

<summoning the author of FCGear>

[-alex-]

How about including it into FCGear add-on workbench?

+1

IMHO integration of this script to FCGear add-on workbench as an all in one feature and in addition the same kind of script to combine 2 stages parametric gears: that would be great

[mario52]

Hi

good macro tanks

is it possible to add groove


https://en.wikipedia.org/wiki/Key_(engineering)

mario

[eaguirre]

Agree adding this to the FCGear would nice. I'm new to FreeCAD so I will found a time to look at the code.

Meanwhile the mario suggestion seems feasible, adding a key hole to the gear will be less work. I may take a look at this but the wiki doc is not that good (the formulas for the parallel key are wrong) but there is link with a nice explanation (https://books.google.ca/books?id=f5Eit2 ... &q&f=false) page 342. So I will add only an option to create square and flat key holes (for a parallel key) in the gear for the shaft.

So I will keep you posted when ready.

Hi

good macro tanks

is it possible to add groove


https://en.wikipedia.org/wiki/Key_(engineering)

mario

[eaguirre]

(GOTO first post to take the latest code)

New version 1.3
- Adding key hub for shaft diameter greater or equal to 6 mm
According to this table takes from mario's link

Code: Select all

		# ----------------------------------------------------------------------
		#  Key Size Chart Standard Metric Keys/Keyways Engineering
		# ----------------------------------------------------------------------
		self.metric_keys = [
			{'over':6,'upto':8,'b':2,'h':2,'t1':1.2,'t2':1,'r':0.08},
			{'over':8,'upto':10,'b':3,'h':3,'t1':1.8,'t2':1.4,'r':0.08},
			{'over':10,'upto':12,'b':4,'h':4,'t1':2.5,'t2':1.8,'r':0.08},
			{'over':12,'upto':17,'b':5,'h':5,'t1':3,'t2':2.3,'r':0.16},
			{'over':17,'upto':22,'b':6,'h':6,'t1':3.5,'t2':2.8,'r':0.16},
			{'over':22,'upto':30,'b':8,'h':7,'t1':4,'t2':3.3,'r':0.16},
			{'over':30,'upto':38,'b':10,'h':8,'t1':5,'t2':3.3,'r':0.25},
			{'over':38,'upto':44,'b':12,'h':8,'t1':5,'t2':3.3,'r':0.25},
			{'over':44,'upto':50,'b':14,'h':9,'t1':5.5,'t2':3.8,'r':0.25},
			{'over':50,'upto':58,'b':16,'h':10,'t1':6,'t2':4.3,'r':0.25},
			{'over':58,'upto':65,'b':18,'h':11,'t1':7,'t2':4.4,'r':0.25},
			{'over':65,'upto':75,'b':20,'h':12,'t1':7.5,'t2':4.9,'r':0.40},
			{'over':75,'upto':85,'b':22,'h':14,'t1':9,'t2':5.4,'r':0.40},
			{'over':85,'upto':95,'b':25,'h':14,'t1':9,'t2':5.4,'r':0.40},
			{'over':95,'upto':110,'b':28,'h':16,'t1':10,'t2':6.4,'r':0.40},
			{'over':110,'upto':130,'b':32,'h':18,'t1':11,'t2':7.4,'r':0.40},
			{'over':130,'upto':150,'b':36,'h':20,'t1':12,'t2':8.4,'r':0.70},
			{'over':150,'upto':170,'b':40,'h':22,'t1':13,'t2':9.4,'r':0.70},
			{'over':170,'upto':200,'b':45,'h':25,'t1':15,'t2':10.4,'r':0.70},
			{'over':200,'upto':230,'b':50,'h':28,'t1':17,'t2':11.4,'r':0.70}
		]

- Fix issue with top
- Fix bug with shaft (now all values are in diameter)

Screen Shot 2019-04-30 at 8.37.44 AM.png (36.03 KiB) Viewed 3788 times

Screen Shot 2019-04-30 at 8.38.47 AM.png (20.36 KiB) Viewed 3788 times

Screen Shot 2019-04-30 at 8.38.58 AM.png (24.14 KiB) Viewed 3788 times

[mario52]

hi

good macro thanks
it misses the icon for the toolbar

i add this line for the window stay to hint (after "# Set UI elements to window")

Code: Select all

		# PySide cette fonction met la fenetre en avant
		MainWindow.setWindowFlags(PySide.QtCore.Qt.WindowStaysOnTopHint)

and "import PySide" in begin

go make a wiki page ?

mario

[eaguirre]

Done version 1.4 has the function to keep the dialog window on top
also I fixed some issues with the size of the top and bottom.

Later I will found the time to understand the code of GearFC so maybe my code could be included in this library
so the Wiki will have to wait a little.

Thanks mario52!

hi

good macro thanks
it misses the icon for the toolbar

i add this line for the window stay to hint (after "# Set UI elements to window")

Code: Select all

		# PySide cette fonction met la fenetre en avant
		MainWindow.setWindowFlags(PySide.QtCore.Qt.WindowStaysOnTopHint)

and "import PySide" in begin

go make a wiki page ?

mario

[NCooper]

I created a GT3 gear and then cut it from a cube to make a socket for a stepper with an existing metal gear. But the outer face of the teeth on the existing gear are wider than the ones generated by the macro and cut into the socket. I had to modify the macro to make the teeth more square and reduce the rounding for a precise fit. Looks like there is too much roundover on the teeth.

Changed the GT3 Gear Data from:
'r1':1.52,
'rs':0.25,

To:
'r1':1.42,
'rs':0.15,

These were arbitrary settings, but they are a closer match to the actual steel gear I have here.