# Unequal tear drop shape

**URL:** <https://discourse.shapr3d.com/t/unequal-tear-drop-shape/27562>\
**Category:** Modeling Questions\
**Created:** [August 27, 2023, 1:28pm UTC](https://discourse.shapr3d.com/t/unequal-tear-drop-shape/27562 "2023-08-27T13:28:54Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Jwardlow](https://avatars.discourse-cdn.com/v4/letter/j/f14d63/32.png) [@Jwardlow](https://discourse.shapr3d.com/u/Jwardlow)\
**Post date:** [August 27, 2023, 1:28pm UTC](https://discourse.shapr3d.com/t/unequal-tear-drop-shape/27562/1 "2023-08-27T13:28:54Z")

</div>

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.

 ![20230827_095036](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/7/9/79ae7167ab4daf180774c06437145c7d1ddd0e64.jpeg)  
 ![20230826_173932](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/7/a/7a7a86d1e8a4716c24203d5933d75224c1838ea3.jpeg)  
 ![20230826_104451](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/e/0/e00f4f838d68bfe9c3102d05d0b689e7e1aedf3c.jpeg)

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

---

<div class="post-metadata">

**Author:** ![KPeter](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/kpeter/32/7644_2.png) [@KPeter](https://discourse.shapr3d.com/u/KPeter)\
**Post date:** [August 28, 2023, 1:58pm UTC](https://discourse.shapr3d.com/t/unequal-tear-drop-shape/27562/2 "2023-08-28T13:58:20Z")

</div>

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](https://www.loom.com/share/fa4fed817aec49c69f705ce63f6b1bb9?sid=04bac341-ec94-47cf-a681-9aaea955bd34)**

_Edit: I just updated the video because the wrong one was posted. sorry for the confusion_

---

<div class="post-metadata">

**Author:** ![Jwardlow](https://avatars.discourse-cdn.com/v4/letter/j/f14d63/32.png) [@Jwardlow](https://discourse.shapr3d.com/u/Jwardlow)\
**Post date:** [August 29, 2023, 8:37am UTC](https://discourse.shapr3d.com/t/unequal-tear-drop-shape/27562/3 "2023-08-29T08:37:51Z")

</div>

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 🙂

---

<div class="post-metadata">

**Author:** ![Jwardlow](https://avatars.discourse-cdn.com/v4/letter/j/f14d63/32.png) [@Jwardlow](https://discourse.shapr3d.com/u/Jwardlow)\
**Post date:** [August 29, 2023, 10:22am UTC](https://discourse.shapr3d.com/t/unequal-tear-drop-shape/27562/4 "2023-08-29T10:22:03Z")

</div>

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.

 ![Cowl 3.PNG](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/9/8/9877d47e6ddfb4d727c5296d831c97633a35ae20.jpeg)