I need to model various involute gears in Inventor. They will be laser cut thus have to be exact. I don't want to use Design Accelerator. The gears are metric, module 6mm. Attached is what I have tried. It doesn't look right to me but it might be. Also, I need to model an internal involute gear. I have little knowledge about gears but know Inventor (6 years experience).
Questions:
How to model exact/true involute gears?
How to model exact/true internal involute gears?
They are imperial, not metric module, but you can use 'em as you please. They are kind of by "the brute force method" as I don't quite have the knack for using equation curves, but should be accurate enough for your purposes. It may be possible to "break" the model at extreme ends of the size spectrum - no guarantees of usability expressed or implied.
For each part, open up the parameters and scroll down to the User Parameters section. (Or just collapse the Model Parameters section.) All the gear data can be seen there with common gear nomenclature for imperial gear parameters. I would recommend unchecking the Immediate Update box prior to making changes, but at most you should only get an update error pop-up if it loses its mind.
I have used these files for generating 3D printed gear sets. Though that is decidedly not the most rigorous test of their accuracy, they do work well.
graemev - I will try doing the "brute force" method and or convert metric to imperial. I just made an equation curve for your pinion gear and it very closely lines up with your spline.
CAG_DRAFT - The laser puts a very clean edge on it so it doesn't need post processing.
I made the imperial gears. The tooth profile looks the same as metric. When moving the assembly around, it reveals that the gears are only in contact a little. Is this because they are modeled wrong or just so little teeth?
FWIW - I have exported tooth profiles and gear faces from Design Accelerator, used wire EDM to cut those gears and run them successfully in racing transmissions. Depends on your exact application, but it's not a bad way to go.