Any way to resize an object to the size (width) of another object?

Hi guys,

Been a while but I am back.

I am playing around and have 2 objects. A "TUBE" and a "LATHE" underneath (to round the bottom part of the tube and close it up.

I love the snap to part of C3D but hopefully there is a "snap to size of another object" that I am missing?


I ask because the TUBE has another dimension than the object I made by importing a spline (PDF) and then used LATHE on that spline. I cannot seem to use the regular SCALE option.

Perhaps there is a way to "RESET SCALE"?
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If I remember correctly (I have my Mac not at hand) you can hold shift key down while dragging one object onto the other in Layers panel and it should adapt the size of the "mother ship".
The coord-System will do a reset.
Frank's suggestion will work if the scale factor of the target object is not 1 1 1.
If you scaled and used Burn Transform it will only change the position of the new object.

You may want the new object to be at world center, or the new position will be offset by it's current position.

Can you share the file?
Thank you guys so much for your quick response as always. I had to smile; because I got a deja vu here where Frank earlier showed me that it is much simpler to "think the Cheetah3D way" rather than the opposite - in my case a gfx designer doing 3D usually combining tools like Illusterator etc for spline work. I think C3D works the best when you do most of the work in C3D starting with a "base model".

I have finally made the leap into 3D prints and were planning to use more CAD than C3D for that (for measurement accuracy); but it seems I can manage most obstacles in C3D as long as I "think like Frank" haha.

So here goes:

Cura (3D slicer for prints) sets size as x millimeters = c3d scale / property size as cm. So scale 5,0 in C3D = 50mm in Cura. That is great, and also why I wanted to understand better the way C3D uses scaling to objects / grids, etc to allow me to think "out of the box" in regards of making designs. However any obstacles met in the past was solved by doing the project more in the C3D way (as tutored by Frank in this great forum over and over for us - so grateful to you all contributing!).

So for example:

I wanted to make a printout of a tube closing it up on one side curving the end side for a nice print out. "The old me" would make a 50% cut of a design in "Illustrator" (in my case Affinity Designer) to have full "artistic freedom" designing and then importing it as a PDF (the vector) using LATHE in C3D. Most other 3D tools used have a set scaling / size system so it has worked great in the past. However - I see over and over that to get the best 3D objects (cleanest too) do the complete think in C3D from the beginning and rather for example do like I did for this project:

I ended up rather doing a POLY > CC subdivide on the end part adjusting the end points in point mode afterwards and again CC subdivide the new adjustments. Worked great.

ZooHead: Thank you so much for your input! I have made it a tad hard for myself using more than one 3D app (Like Silo 2) and forget sometimes what is capable in what app :) Great tip you solved for me before asking to always start at world center!

(The file was saved over as I progressed on this)

Last Q for now: Is there a way to "scale to grid"? Then I could scale to grid regardless of the state of the object (editable or not)

Again - Thank you SO MUCH for all the years contributing to us all! Hope to one day give some back.
Last Q for now: Is there a way to "scale to grid"? Then I could scale to grid regardless of the state of the object (editable or not)
Unfortunately not possible. We have just 3D View Grid, Big and Small Step color adjustments in Preferences/Colors. I usually have the Small Steps 100% transparent as they often gets in my way.
Regarding the PDF import scale can you use Preferences->Files->.pdf->Import = 0,035278 and see how that goes?
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Hopefully a future update can make a "snap scale to grid" function? Might not be alone wanting to use something like that, but no problem will do it the C3D way. It is just a matter of what you are used to from before I guess.
* The entry fields for defining parameters in the properties panel do accept the basic math(s) symbols, +, -, *, /. Of course, this is in-directly related to the grid you are deploying and is just a simple factor to modify the existing values of x, y, z (for position, rotation and scale) plus a few more parameters.
* If an import results in awkward values with 4 decimals it may simplify re-scaling the object in 3D models where precision is required for a clean fit between two components.
:unsure:Alternative Grid Options:
* Note that you can hide the default grid; if frequently used, you can define a hotkey which works as a toggle.

Screenshot 2023-10-23 at 18.23.26.png

* Via creating sub sectioned planes in XZ (plus other planes, if required) you can define alternative grids, displayed as wireframes. Clearly, these must be invisible to the renderer.
* In the panel for the Transform tool you then re-define the raster width to inches, Roman cubits, light years or whatever you need for snapping.

* AFAIK, C3D provides the tools and functions to operate in a customised grid. Dedicated :sick: Rasterfarians may wish to experiment to achieve such trickery...
Another method could be making planes of any size and iterations to your liking, calling the script: Polygons to Splines and take the result as a grid. Just saying.
:whistle:Last Addendum:
* There also is a script by Master Hiroto to generate 2D / 3D grids which permits setting size and step. This generates
1 three 2-dimensional orthogonal custom grids, one on each of the design planes, XZ, XY and YZ
2 a single 3-dimensional grid

* You can twiddle the scales and as a result you can display a grid with different steps in the X, Y- and Z-direction.
* As with Frank´s suggestion above, this is a spline object, visible in the editor but ignored by the renderer.

* It is, inter alia, quite useful for modelling historical buildings. Bays in ecclesiastical architecture, be it Norman, Romanesque or Gothic (including my hero, Antoni Gaudi) come in all sizes and the vertical grid is unrelated to the horizontal offsets of columns.

* As mentioned above, C3D provides sufficient tools which can be deployed after a bit of creative brainstorming (solitary version or the JAM in this forum) to achieve alls sorts of trickery.