Coil Spacing - needs to be specific width

[HenryCarlson124]

Hello,

I am trying to make an engraving into this cylinder for a cam follower that is 6.5mm in diameter so I need it to be 6.5mm wide at all parts so that the follower fits snuggly. How would I do this. I made the sketch on the side of the cylinder and then coiled it around a work axis in the middle of the cylinder.

I can share more screenshots and info if that is needed. ( three screenshots attached )

Thank you in advance!

[SBix26]

Is your cam follower tapered?  If it is cylindrical, then you need your cam slot sides to be parallel, not angular.  The most accurate cam path will be produced by a solid sweep (available in Inventor 2020 and later) of a solid the shape of your follower (plus clearance!!*) along the appropriate path.

While pictures are helpful, a model file (.ipt) is much more likely to get people to post different ways to solve this.  And don't forget to let us know what version of Inventor you are using.

*Note about clearance: you must provide some clearance for your follower.  No machining (or other fabrication) process is perfect, so you have to make allowance for slight variations from perfection.  A Ø6.5mm follower will be 6.5 ± .005 or some such number.  Likewise the slot.  A 6.505 mm follower in a 6.495 mm slot will be... dysfunctional?

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Sam B

Inventor Pro 2023 | Windows 10 Home 21H2

[HenryCarlson124]

I attached the part file. I was not worried about clearances right now because it is completely digital. I will not be making this model outside of inventor. My follower was just going to be a simple rod of diameter 6.5mm which is why I wanted the width to be that. I don't have much experience and was looking for something simple.

Thanks for the reply!

[johnsonshiue]

Hi Henry,

The precise geometry in this case has to be done by using Solid Sweep (sweeping the cam tool along the helical path).

Many thanks!

[SBix26 · Accepted solution]

Here's my first try using solid sweep (Inventor 2020 format).  I'm sure this can be done more neatly, but it's past my bedtime...

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Sam B

Inventor Pro 2023 | Windows 10 Home 21H2

[IgorMir · Accepted solution]

Hi,

Here is a model (IV2020 format), similar to what Sam has offered. With just a few less entries in the browser. 🙂
Cheers,

Igor.