Imagining the solid piece of tubing (see image below) created with “OffsetSrf” as four (4) watertight surfaces, how do I remove the end surface without using “Explode” (creates too many opportunities for a mistake by someone learning)? Haven’t found anything akin
to my CAD program’s “Deep Select”………
And given a new end cap surface, a fillet surface, & a trimmed outer diameter surface, what command do I use to reconstitute the solid object?
Art
ExtractSrf with Copy=No will detach the selected surfaces. Then Delete the extractred surfaces if desired.
ExtractSrf help
David-
Thanks!! exactly what I was looking for AND works like a champ.
Art
Please upload a .3dm file with the geometry involved in your question. Export can be used to create a file with selected objects. The file can be uploaded by dragging the file to where you type a post, or by clicking on the vertical arrow icon above where you type a post.
What is an “Iplane”? That is not a term I’m familar with in Rhino.
Thanks.
See the attached file for what I get using the curve in your file to create the IPlane in the trim operation.
trim objects 1500 012021 DC01.3dm (1.9 MB)
My sequence:
Command: Trim
Select cutting objects ( ExtendCuttingLines=No ApparentIntersections=Yes Line ): infiniteplane
Select planar object to use as a temporary pseudo-infinite plane ( 3Point Vertical ThroughPoint AroundCurve NamedCPlane CPlaneXY CPlaneYZ CPlaneZX WorldXY WorldYZ WorldZX )
Select cutting objects. Press Enter when done ( ExtendCuttingLines=No ApparentIntersections=Yes Line )
Select object to trim, select pressing Shift to extend ( ExtendCuttingLines=No ApparentIntersections=Yes )
Splitting… Press Esc to cancel
Creating meshes… Press Esc to cancel
Select object to trim, select pressing Shift to extend. Press Enter when done ( ExtendCuttingLines=No ApparentIntersections=Yes Undo )
Select object to trim, select pressing Shift to extend. Press Enter when done ( ExtendCuttingLines=No ApparentIntersections=Yes Undo )
Creating meshes… Press Esc to cancel
David-
thanks! exactly what I expected using the infinite plane for the trim object. is using the curve for the trim object incorrect/higher risk/poor practice…? the curve is needed in the next “sweep2” so it’s not a question of extra work
Art
Hi @artesmith,
If (as previously suggested) you pull the tolerance down to a more reasonable value like 0.001 then your ellipse will trim the outer surface directly without shooting off in a mad direction.
Alternatively if you are determined to keep that tolerance you will get a trim if you either, a) pull the ellipse to the outer surface (your outer surface is in two parts so you need to select both when the pull command asks for a target) or b) use an isocurve (again, you need to do both the two parts) in place of the ellipse.
regards
Jeremy
No you don’t really need the curve, you can use the edge created by the trim (you will probably need to use the chainedge option within sweep2 because your surface is in two parts).
Jeremy
Jeremy-
thanks for your posts!! have I done something to cause the surface to be represented in two parts or is it a Rhino thing?? a surface thought to be one object when it’s actually two would explain a great deal of the extremely curious behavior I’m encountering… also tracked down the tolerance setting and reduced it some. it’s now time to see if the three resulting surfaces can be converted to a water tight solid…
Art
other than learning some new commands (a good thing and the point of the exercise), the surface centric approach didn’t get me any nearer the filleted solid I’m looking for. the attached collage shows the highlights of the approach and the resulting “no joy” outcome. a copy of the latest version of the file is also attached. any additional thoughts on what I might be doing wrong??
Art
Hi @artesmith,
I believe you are using the CreateSolid command - which is intended to create a solid from surfaces that overlap one another. It is probably failing because your surfaces meet rather than overlapping. As it says in the Rhino Help for CreateSolid, Join is a better command in this situation. Using Join your object closes.
Regards
Jeremy
Yes - but I don’t know what…
In the other thread I posted a version of your model in which I had remade a couple of sections of your pipe at a lower tolerance by extruding circles to create the straight sections and revolving the circles about the centres of your guide arcs to create the curved paths. If you check those out you will find they formed complete surfaces, as splitting isn’t a normal occurrence.
(Note though that a cylinder in NURBS always has a seam along its length because NURBS are four sided - think of a rectangle rolled into a tube).
Jeremy-
a huge thanks for both your posts; “Join” does the trick for creating a closed/water tight polysurface (aka: solid) AND provides the means to use the simpler “Extrude”/“Revolve” approach versus the “Sweep1” I’ve been using to avoid two surfaces!!!
Art
Glad its working out. I don’t know if you are coming to Rhino from another tool, but it’s easy to miss out on the good stuff in Rhino because we have preconceptions about what the commands mean. I don’t know how much you have learnt already, but if you haven’t given the McNeel tutorials a go then I’d strongly recommend them. Also the help system is great for browsing the commands and finding out how to use them. The first thing I drew in Rhino was an oil cooler duct and if I’d had that advice back then I’d have done it quicker and better. Ten years on I’m still learning to do it quicker and better…
Regards
Jeremy
attempting to put the new found insight into “Join” and “Extrude” to work I’ve run into another brick wall… “Join” won’t join an ID surface created with “Extrude” and “ExtendSrf” won’t extend the end of the exposed ID surface. is there something wrong with the exposed end of the ID surface and if so, where is the information that tells me it’s wrong/bad/…??
Art
join and extend problem 1400 013121.3dm (1.2 MB)
Hi @artesmith,
ExtendSrf won’t extend the inner surface because it is part of a larger assembly. You need to run ExtractSrf or Explode first. Once the surface is unconnected to anything else it will extend.
Join will certainly connect an extruded surface to something else that has a co-located edge with it. You don’t say what you are trying to join to and I can’t see anything adjacent - I hope you are not expecting to join to something remote…
I do think you would benefit by taking time out to do the tutorials - then you’d have a structured way to learn how these basic functions work in Rhino.
Good luck
Jeremy
Jeremy-
I’m currently of the opinion my problem isn’t lack of tutorials, it’s vocabulary/documentation nuances. “Create Solid” doesn’t sound like a special case tool to someone new to Rhino. the help function explanation for “ExtendSrf” says: The ExtendSrf command moves a surface edge to lengthen a surface.; nothing about not working with polysurfaces…
I’ve attached a screen image of the “Join” geometry and failure message; the working file hasn’t changed.
Art
It’s not clear from the image what you are doing here. But if you have created the blue surface by extruding the inner blue circle back to the end of the assembly and then tried to join it to the assembly, it isn’t working because the blue edge isn’t coincident with an edge on the assembly (the blue circle has a radius of 0.7775", the inside of the assembly has one of 0.7463"). From the help, “You can join surfaces and polysurfaces that touch at naked edges.”
Listen, I’m really sorry, but I can’t keep spending this much time explaining things (apart from anything else I have two projects of my own to complete). I hope you can find a way to get to grips with Rhino because it can do some really cool stuff.
ATB
Jeremy
