Edge Triming of Complex Curved Solids

[fabian_borg]

Hello

Following to my previous post and the great guidance received here, I have stumbled into another problem when trimming edges on complex curved solids created with conic curves (splines). The solids are extrusions from fully dimensioned sketches. 

As per my previous thread, this time round I would like to modify the edges of complex curved solids. As per the screenshot I would like to lower Edge A by -10mm and raise Edge B upwards by 10mm while Face A and the hidden Face B (Opposite of Face A) will smoothly ramp to follow the new edge.

I have tried a lot of options, including a sketching the frame (make faces, merge into solids) or use projection over sketches but did not succeed.

The attached f3d is the actual file with the right dimensions and positioning of the solid. A screencast would help me better understand how to accomplish such.

With best regards to all

Fabian

[TrippyLighting]

Not sure why you would need to trim edges. Frankly, I am not even sure why you are working with conic curves and what it is you are trying to achieve. Usually you'd create two profiles, one being your sketch 4 (sketch5 is completely unnecessary). You'd create a second sketch on an offset plane wit the desired dimensions.

The question is of course what those dimensions would be. If you use the same curve endpoints (you can project those from your sketch 4 into the current sketch on the offset plane) and then simply move the control points of these 2 conic curves up 100 and down 10 mm, but keep the same RHO value of .75 then you get intersection curves not suitable for an extrusion profile.

 

So I am wondering if fit point splines arent more suitable to what you want to achieve.

[fabian_borg]

@TrippyLighting 

Sorry still a noob with terms and Fusion 360. I meant to alter the position of Edge A by -10mm and raise Edge B by 10mm. I used the word trim as in my other thread, I was recommended to create a cut solid to trim the main solid to the desired final measurments.

Would your solution work with just one edge selected please

[TrippyLighting]

I am not sure this is exactly what you want and you did not really answer most of the questions I asked but a model is attached.

[TheCADWhisperer · Accepted solution]

See Attached.

[fabian_borg]

@TrippyLighting 

Not really, the edges that need to be amended are Edge A and Edge B as per the original screenshots attached.

Will try and create an illustration to guide you better.

[fabian_borg]

@TheCADWhisperer 

That is exactly what I was after, but how did you manage that please, so that I could learn.

I am putting your advices to constant use 🙂

[TrippyLighting]

Oh oops ... completely misinterpreted that 😉

@TheCADWhisperer has got you covered!

[TheCADWhisperer]

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@fabian_borg wrote:

@TheCADWhisperer 

That is exactly what I was after, but how did you manage that please, so that I could learn.

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It's all in the Timeline - no secrets in Fusion.

[fabian_borg]

@TheCADWhisperer , I have followed the timeline but questions still come to mind as how you determined the cutting shape and dimension. I also cannot come to terms on the projections as when I hover on them, I cannot see any links despite being in model or sketch edit views. This is my third week of using Fusion so I am really on my very first steps and I am eager to acquire the CAD logic and learn Fusion 360.

I really wish to learn how to accomplish your results for future use. Would really appreciate if you do a screencast of that.

With best regards 

Fabian

[TheCADWhisperer]

This does not look like anything real to me.

What are you trying to model?

[fabian_borg]

@TheCADWhisperer  my aim is to model custom guitars (new designs) hence the 44.45mm height of the models due to the tremolo bridges, pickups and other electronics within the guitar. I am used to manual wood working the bodys, but wish to embrace CAD and CNC that will open up the level of precision I am after for base body works and then after complete the manual finishing. 

I think, I just figured out that the projection in your model was determined by the curved surface at sketch level.

Edit 

The projection I tried got a different axis to the one you did 😐

[TrippyLighting]

There are a large number of threads on this forum where string instruments are modeled, including guitars. It might serve you well searching the forum for it as this is territory well covered.

There  is also a Facebook group for Fusion 360 luthiers.

i know that @jeff_strater had assembled a nice list of these threads somewhere.

[fabian_borg]

@TrippyLighting  thanks for the information on the specialised groups

[fabian_borg]

@TheCADWhisperer  I managed to overcome my problem to recreate the projections you created in your file. The issue was that when you created sketch6 you have chosen a face as a plane. The timeline doesn't reveal this so I had to find my way about through a lot of trials. Thanks just the same for your advice on how to accomplish the desired modification to the solid. That was, while hard for a noob, I learnt something 🙂