Unequal tear drop shape

[Jwardlow]

Hi There, I need some help as im fairly new to CAD in general. I am trying to create an engine cowl for an aircraft. Effectively trying to create the shape so that I can then take sectional profiles that can be sent to a CNC router service, to cut the profiles, that I can later stick together and fill with foam from which to make a plug for fibre glassing.

However, the bowls around the engine cylinders are quite difficult as they are not symmetrical, I have tried a few different methods. I have tried to revolve a shape around an axis, which wasn’t suitable. I have also tried to draw various different profiles and then loft between them but this ends up looking too blocky.

What ever shape is finally created, I would also like it to be hollow so that I can ensure clearances between the cylinders, walls, spark plugs etc.

Any Ideas on the best work flow. As you can see below images, the original engine cowls that I am not trying to fully reproduce, but that in general is the overall idea. And then you can see two of my progress attempts but they’re very blocky.

Any help or advice on best tools to use, or a kind of workflow guideline would be greatly appreciated.

[KPeter]

Hi @Jwardlow,

Shapes like your example are regularly combined from a small number of simpler bodies. In this case, A lofted box for the main cover and two revolved parts for the cylinders.
Please see the video below about a possible workflow:

Teardrop Shape

Edit: I just updated the video because the wrong one was posted. sorry for the confusion

[Jwardlow]

Hi Peter,

Thanks for your great video reply. I will have another go at reworking my design using your suggested workflow, and see if I can get something that looks more aerodynamic than my first lego attempt

[Jwardlow]

Hi Peter thanks once again for your help. I feel quite a lot better with the workflow now, and have managed to do a v1 concept. Will go back out to the airfield later in the week to do a more refined scan of the engine and cowl frame so that I can get a tighter model, but it has helped a heap with the work flow. Thanks once again.