How to Taper a Side by Degrees


#1

I’ve drawn a small box 1" x 0.5" x 0.3" that I would like to have tapered sides so it can be more easily injection molded. I want to taper the sides by 1 degree but I can only figure out how taper the sides by “Distance” and don’t know the distance I would need.

Does anyone have a solution?


#2

You can use a construction line as a reference for moving a line…


#3

Well, from basic trig a 1 degree taper causes a slope of 0.01745, that is, a decrease of that times the length of the taper. You will likely have to scale you block up while making such a small change or you will likely see issues due to SketchUp’s merging of vertices closer than about 0.001".


#4

Could he not do the same as this with the rotate tool and rotate the face by 1 degree?


#5

He could but it would shift the top face, too.

The vertical edges of the box need to be lengthened but Rotate won’t do that.

@RSalpeter, I expect you’ll want to add the draft to all sides of the box. Is it important that the draft be exactly 1°?


#6

Obviously not, as Dave demonstrates!
Not the simple solution anyway, too messy to clean up.


#7

If the tapering is symmetrical, the scale tool together with CTRL could be an alternative…


#8

Put vertical guides on opposit corners, rotate by 1 degree, draw line and push through?

Edit-but other two sides are still messy


#9

This will work for the first two sides, fot the next two you need some intersection and cleanup afterwards.


#12

You could copy an edge with Rotate to create a surface that is angled 1 degree, then use Follow Me to drag that shape around the exterior.


#13

Great idea
My lack of follow me use showing there


#15

Thank you everyone for you ideas and suggestions. Not only did you give me effective solutions to my problem, I remember now what trig is for…


#16

Just a random comment …

In a former life, I did 3D modeling for injection molds. The OP’s issue with draft was commonplace. One of the more difficult shapes was simple in concept:

The change in angle going around the corner was always problematic for the corners as well as the sides.


#17

Its been a while but this post stuck in my mind, heres a few examples I did when I had some spare time

You might find them useful.