Have a question for those into 3d modeling.

[Sabre F-86]

I've seen some of the great items being produce, and I want to make some of my own. So, just how do you get the information you need to make up the model? For instance I'm  looking at trying to make Mk-82 bombs to replace the miserable ones in my Trump A-10 Kit. I've looked round and so far, the only dims I can find are length, max diameter and fin span. I've done a fair bit of drafting and looked at various aircraft cross sectional drawings, most of which don't have measurements which leads to the question. How would you be able to plot the casing curve of a KMk 82 without any measurements?  I am just getting into FreeCad 0.18, and eventually I'll try to draw one and make the model. What do I do? Measure photos? Or measure drawings? That's for a simple enough project. How would you go about making the model for a radial engine or other complex item?

[Finn]

If you can find a larger copy of this pic, it has lots of info:

 

 

Jari

[Dandiego]

Sabre, I use drawings like those that shown in the previous post and import them into the cad program. You can then plot points along the edge of the drawing to get the shape right.

 

I am very new to cad and struggle to create anything more than a basic shape. I watch lots of videos and then practice.  Sloooooooooooowly getting better.

 

Dan

[Sabre F-86]

Thanks for the replies. I figured it was much as you described. First things first, master FreeCad. In the mean time I'll keep my eye out for good references.

[jenshb]

I use Solidworks, and that program allows you to import images onto a sketch plane.  You can change the opaqueness of the image and then use that as a base to trace or sketch lines, arcs and circles.  In your case, you'd probably be looking at creating a spline and rotating that around an axis.

 

If your program doesn't allow importing images for tracing, then you will need to create waypoints in your sketch that you calculate from drawings or photos using known dimensions.