topic Re: Changing Gear Parameters in Fusion Design, Validate & Document Forum

Changing Gear Parameters

richardsalzman — Mon, 09 Mar 2026 18:37:32 GMT

I designed a few gears that I want to change the modulus, diameter and root filet radius. I used the spur gear add-in to create them. I want to increase the modulus and root filet radius just a bit.

Is there an easy way to modify the current design? If I draw a new gear with the add-in, it will create a new sketch, and all the parametric features down the line will not follow.

Any thoughts?

Richard

Re: Changing Gear Parameters

davebYYPCU — Tue, 10 Mar 2026 04:19:11 GMT

I want to increase the modulus and root filet radius just a bit.

Not going to be easy, the sketches are not fully defined, some items are fixed (green) and not even dimensioned.

Changing the Fillet, Extrudes and hole is fairly straight forward.

Might help...

Re: Changing Gear Parameters

Drewpan — Wed, 11 Mar 2026 00:36:23 GMT

Hi,

I think you could maybe clone the Gears (Copy/Paste New each one) and then

run the Add-in again and change each parameter.

Cheers

Andrew

Re: Changing Gear Parameters

TheCADWhisperer — Wed, 11 Mar 2026 02:45:18 GMT

@richardsalzman wrote:
Is there an easy way to modify the current design?

Any thoughts?

@richardsalzman

How motivated would you be to go through the process of creating a configurable gear.

(It would take some time as I am only slightly motivated to go through the steps - mostly because of some limitations in Fusion, but I think we can get past those.)

Re: Changing Gear Parameters

richardsalzman — Wed, 11 Mar 2026 04:17:46 GMT

Thanks for your thoughts. Not necessary at all. I am recreated the gear without much issue. I ran into two questions. I will post tomorrow. Machining a gear as we speak.

Thanks so much for all your help.... Richard

Re: Changing Gear Parameters

richardsalzman — Wed, 11 Mar 2026 21:13:03 GMT

I found your video clip very helpful!!! Here are the few issues I ran into:

1. I am not familiar with deleting a face on a body. I was successful with one attempt, but not on this one. It didn't effect this part, but I would like to know more about deleting a face.

2. I don't understand why reducing the size of this circle say to .55" makes the drawing fail:

3. Lastly, can you provide more info on how you used the long select to select sketches. I have not seen this before.

Thanks again... Richard

Re: Changing Gear Parameters

TheCADWhisperer — Wed, 11 Mar 2026 21:30:33 GMT

@richardsalzman

Can you File>Export your *.f3d file to your local drive and then Attach it here to a Reply?

For this image to be useful for diagnosis you should have expanded this in the browser and expand the Bodies folder to show that it is one body.

Without additional explanation (or the actual file) I don't see what you are referring to as a "failure".

But that certainly doesn't look like a logical size for the Pitch Circle.

Maybe we should have gone through the step-by-step process of creating a gear.

Re: Changing Gear Parameters

richardsalzman — Wed, 11 Mar 2026 21:46:06 GMT

Sorry, I forgot to attach the file. For starters, the gear was created with the Add-in Spur Gear plug-in within Fusion. If I reduce the diameter above from .65 to .55, I can no longer apply filets. I don't see what is happening.

Here are the parameters for the gears:

Re: Changing Gear Parameters

TheCADWhisperer — Wed, 11 Mar 2026 23:12:15 GMT

@richardsalzman

(view in My Videos)

Re: Changing Gear Parameters

richardsalzman — Thu, 12 Mar 2026 00:28:16 GMT

Thanks for the excellent explanation. The problem I was having is that when I reduced the radius of the center from .65 to .55, the filets had error as shown below. I am quite certain that this happened because I did not join the "spoke" to form one body as you pointed out. I was not aware of the fact that if it is one body and you delete a face, it will heal itself. Really cool stuff!

The reason the distance between centers for the gears is too large is because I changed the gear design (modulus, tooth count and root filet radius) and have not updated the drawing to reflect the correct distances. I am machining these gears from aluminum and wanted to machine one first, then update the rest of the gears. Below is the first gear I just machined.

Thanks so much for your help!

Best... Richard

First gear completed: