Making a partial-depth slot around the surface of a cylinder

alan_budden

Given a cylinder (let's say 20 mm diameter), I would like to make a slot in this cylinder that is 3 mm diameter and goes 45 degrees around the outside of the cylinder, 0.5 mm deep.  This slot should match the result that would be obtained if the cylinder were placed in a rotary table on the milling machine, a 3 mm slot drill plunged 0.5 mm into the cylinder and then the cylinder rotated through 45 degrees.

I've tried a lot of different attempts at doing this, including:

* Create a plane tangential to the cylinder, create a sketch with a circle and then create a second sketch containing the 45 degree arc through which you want to sweep the sketch - I couldn't find a way to sweep it
* Create a plane tangential to the cylinder, create a sketch with a circle, extrude it and then try to stretch that object through 45 degrees - I couldn't find a way to stretch it
* Create a plane tangential to the cylinder, create a sketch and revolve it - the revolve wouldn't work
* Create two planes tangential to the cylinder, 45 degrees apart and two 3 mm circles - try to find a way to join them up!

Please can someone offer a method that would work for this?

Jake_Rosenfeld

Hi again Alan,

After I write that last response, I think I figured out what you were actually asking.  I added a part studio "Side Slot" which may be a better response to your question:

https://cad.onshape.com/documents/9800461f54d139d4b5d410ac/w/10bb1d2e8e3387c4d470ba76/e/dd54585637b86a325b0371e7

As before you can copy the document and explore how I did this, but if you have any confusion please don't hesitate to ask!

Jake_Rosenfeld

Hi Alan,

Is this what you are looking for?

https://cad.onshape.com/documents/9800461f54d139d4b5d410ac/w/10bb1d2e8e3387c4d470ba76/e/887c73f55c0b8d473f152b60

I tried to make a couple slots for you.  The first (Original slot) is just a revolve-remove of a 3mm x 0.5 mm cross section 45 degrees.  The second (Realistic slot) tries to take into account that a drill bit is circular.

If either of these are what you are trying to accomplish, feel free to copy the document and double click on the features to see what their inputs were.

Jake_Rosenfeld

Hi again Alan,

After I write that last response, I think I figured out what you were actually asking.  I added a part studio "Side Slot" which may be a better response to your question:

https://cad.onshape.com/documents/9800461f54d139d4b5d410ac/w/10bb1d2e8e3387c4d470ba76/e/dd54585637b86a325b0371e7

As before you can copy the document and explore how I did this, but if you have any confusion please don't hesitate to ask!

jakeramsley

https://cad.onshape.com/documents/795f17f27d9d40fbd61d56b8/w/4a0e757d899595d77ac702ae/e/e8bbc21feb7d0dfb3d391d0a

Do you mean something like this?

NeilCooke

C'mon guys, it's like this: https://cad.onshape.com/documents/52054548b41407b0d0c1f8e8/w/bf6e38cb44fdf0562ef8075a/e/628fbd006ac2f4e65a6d755d

alan_budden

Hi All,

Thanks for providing the answers so quickly.  It's interesting to see the two different approaches that NeilCooke and Jake_Rosenfeld have taken.  I've accepted Jake's answer as it seemed closer to the way I would intuitively do it, but that might just be me.

Thanks again.

Alan

chris_hockaday

I had a similar problem, and this really helped. However, I found a slightly easier solution - create the rectangular groove, as in the accepted answer above, then simply fillet the four inner corners by half the slot width