Detail on crank

tarek_mustafa

Hallo,

I struggle to get the winding on my crank.
In a first attempt I thought to put a Helix on the crank and than cut it in the length I need it but I could find a way to realise it. 









Any help to solve this problem is much appreciated. 

Best regards,
Tarek

coleman

Hi Tarek,

Going off the sample picture, the crank shaft has a bigger OD where the threads are and it is relieved on each end.  You will need to grow the diameter that interfaces with the worm gear (revolve around centerline).  Then you can add the helix to this new larger region.  This will be the major OD of the drive.  
Next, sketch the profile of the thread (looks like an Acme) on a plane tangent to the start point of the helix and Sweep cut (remove) using the sketch profile and the helix as the path.  

Then you will end up with something like this:

To recap:

1) Increase major diameter of crank in middle section (revolve sketch around centerline) 

2) Add helix to new section on crank (this will limit the helix length and it will be slaved to the bigger diameter) 

3) Draw thread profile (acme thread) on a plane tangent to the start of the helix.  You can dimension for the correct depth (minor diameter) 

4) Sweep the sketch with the helix as the path and select the bigger diameter as the merge with

Good luck

The music box is looking great!   

lougallo

@tarek_mustafa Use a gear mate.  Select the two revolute mate connectors you have and set a gear ratio between the crank and the drum.
UPDATE:  Maybe I should read the entire post.... Sorry.  Yes look at @Coleman 's answer.  

You can add that normal plane by adding a new plane with "Curve point" selected the endpoint of the helix and the helical curve.

coleman

Hi Tarek,

Going off the sample picture, the crank shaft has a bigger OD where the threads are and it is relieved on each end.  You will need to grow the diameter that interfaces with the worm gear (revolve around centerline).  Then you can add the helix to this new larger region.  This will be the major OD of the drive.  
Next, sketch the profile of the thread (looks like an Acme) on a plane tangent to the start point of the helix and Sweep cut (remove) using the sketch profile and the helix as the path.  

Then you will end up with something like this:

To recap:

1) Increase major diameter of crank in middle section (revolve sketch around centerline) 

2) Add helix to new section on crank (this will limit the helix length and it will be slaved to the bigger diameter) 

3) Draw thread profile (acme thread) on a plane tangent to the start of the helix.  You can dimension for the correct depth (minor diameter) 

4) Sweep the sketch with the helix as the path and select the bigger diameter as the merge with

Good luck

The music box is looking great!   

tarek_mustafa

@Coleman That is great! Thank you very much. @LouGallo thank you as well, much appreciated.

coleman

tarek_mustafa You are welcome sir.  Let me know if you have any questions and Ill be glad to help