A tiny problem?

Rhino Rhino for Windows
1

hi you fine people :slight_smile:

I have this minor problem, i’m designing some seat cushions for a 40 ft boat and have digitized the seat area. the base cushions are simple but the back of the fiberglass hull is curved as you can see in the model.

what I need to do is cut down the cushions from the bottom up by 75mm so they sit above the base cushions

Is there a way to offset the bottom line in the Z+ direction but to follow the contour of the of the curves as it rises because when I offset normally it doesn’t really work correctly because the offset curve is is just vertically projected which is no good seeing as the backrest is angled.

looking from the front of the seats I have copied the backrests on both sides and am working on the port side ( RIght to non boaters looking from the front )
The single points are fastener positions, and the badly made hand rail is irrelevantseating 1 - working 1.3dm (5.8 MB)
for this problem

kind regards
Richard

2

Hi Richard - this is an offset of the bottom curves you’re after, correct, not strictly moving in World Z? Is there a surface for the bottom? If so Offset that… Wait, I zoomed out - it looks like you already have that - is this the curve you want?

image
image.png887×459 8.46 KB

-Pascal

1 Like
3

you da man Pascal :slight_smile:
thats it ! i can then build a cushion with depth from that profile that sits on top of the base cushion.

this is what I am re-making,

IMG_20180915_102721
IMG_20180915_102721750×1332 243 KB

next thing to learn is the velcro tabs on the top edge that roll over the hand rail . :slight_smile:

thank you again Pascal, but how did you do that :wink:

Richard

4

Hi Richard - it’s a little convoluted but:

  1. Join the top and bottom curve bits into two curves.
  2. Loft them, with rebuild, maybe 32 points in the Loft dialog for enhanced cleanliness.
  3. OffsetCrvOnSrf the lower curve by 75. The curve is a little messy so it makes a bunch of weird offsets but the one you want is in there someplace. It might be OK to Rebuild the curve to 32 or so points, then offset.

-Pascal

1 Like
5

hiya

I will try that over the weekend and let you know how I get on , thank you.:slight_smile:

Richard

6

Hi Pascal
I’m struggling to get this working, i can use the OffsetCrvOnSrf ok but the lines it is giving me are not usable ? …
correction, i tried it one more time and it all went perfectly and output just one line ?? I have no idea why 5 times it didn’t work and then it did… v odd ?

Richard

7

Hi Richard - I got a jumble when I did this, but the curve I wanted was in there, someplace.

-Pascal

1 Like
8

HIya
I appreciate your help, I got the jumble of lines too but the last time I tried I got just one line so job done :slight_smile:
…
Richard