# Help! Please can you help me with my booleaning and splitting problems

Please can you help me because I need to do this for my A-level project and it is due to be handed in on the 24th April. I have to get it 3D printed by Friday.

I have had several problems with booleaning internal components to the head of my project. This has made it very hard to split so that the product is in two symmetrical parts. I have read all the help information available and spent hours trying to solve the problems. Unfortunately, I haven’t been successful so I have attached the information about each problem in a zipped document containing a word file. I’ve also attached my project so that you can see the problems too. ANY HELP WOULD BE GRATEFULLY RECEIVED.

Hi Kyran - one problem is that the spherical object has no thickness. I’m not sure how you want to resolve the details, but you cannot 3d-print the object as is. Ultimately you’ll need an object or objects that shows no naked edges (`ShowEdges > Naked edges`)and has some minimal thickness that can be printed.

-Pascal

Hi Pascal,

When I try and create a new sphere, it doesn’t give me an option to set a thickness for it. What shall I do to set a thickness? Also, how am I meant to resolve the naked edges problem when some of the edges can’t be selected to join to another edge?

Kyran

Hi Kyran - I do not know what all you may need to do more, but I’ve attached a closed solid of a simplified version of your part - it has a wall thickness in the roundy part of .2. This is just to give you an idea what to shoot for - see how the thing is a closed solid with the internal volume. i.e. the print material, completely enclosed by surfaces?

-Pascal

Hi Pascal,

When you initially made the spherical object, how did you set the thickness? I can’t see how to do it. Whenever I make a sphere, it only gives me the dimensions as in radius, circumference etc.

Kyran

Hi Pascal,

Do you have any tips on how to get rid of naked edges fast? Will I need to start again knowing that the thickness of the sphere isn’t correct, or can I modify the thickness of the existing sphere?

Kyran

Hi Kyran - `OffsetSrf` However, pure, plain spheres (not what we have here) in Rhino are solid, and offsetting them will create spheres inside of spheres, not spheres with thickness. Note the part is not just a sphere - the inner faces are connected to the outer faces, if you follow the surfaces down the inside of tube and out and back up the outside of the tube. In other words inside and outside surfaces are all connected to enclose one volume. When you get done trimming and joining and Booleaning, if that is a word, that is how the topology of the object needs to be. There are a lot of ways to get there, depending on the situation.

-Pascal

Hi Pascal,

What do you recommend I do first? Also, there is obviously going to be some naked edges where certain objects won’t connect to anything. If I need to remove all naked edges, what do I do with those?

Kyran

Hi Pascal,

Also, with regards to the OffsetSrf tool, how will that help me with removing the naked edges?

Kyran

Make sure there are surfaces that have edges there - you may need to trim surfaces for example. It seems like you’re trying to do this all at once without really having worked in Rhino previously - that will be hard…

-Pascal

Hi Pascal,

Is there any way, as I’m a visual learner, you could edit my document so that I can see how what your advising me to do, is done? I’m struggling to see what I need to do to solve the issues I have.

Kyran

Hi Kyran - I’d poke around here:

http://www.rhino3d.com/tutorials

That should get you started.

-Pascal

Hi Pascal,

Thank you for your help. Just to confirm, does the thickness of the handle have to be the same as the thickness of the sphere? (0.2cm)

Kyran

Hi Kyran - that is entirely up to you and the requirements of the printer - Rhino does not care, as you can see, my example had more thickness in the handle - in fact it does not have enough thickness in the handle, I just noticed, because the scallops cut through to the inner cavity - that is in fact NOT valid for printing, I’ll upload a fixed one in a moment.

Here’s a more careful version, more like what you should be after, I would say-

-Pascal

Hi Pascal,

Some of the naked edges don’t have another edge they can join to. What do I do then? Is there not a quicker way of getting rid of the naked edges? I have 360+ naked edges and that’s going to take many hours of trying to use the ‘Joinedge’ tool. I don’t know how I can make this work in time for my deadline day.

Kyran

Hi Pascal,
Thank you for the red drawing with the different thickness. Once you’ve created a line drawing like that, can you revolve it to create the product? I apologise for all the questions but I have never worked with Rhino before and my Teachers at Sixth Form College also don’t know how to use it either!

Hi Kyran - this may give you an idea of one way to proceed - btw the Revolve idea is fine, the problem is your object, the scallops on the cylinder and the ovalized head, are not revolved. You could certainly make the cylindrical part from a curve that is revolved rather than from a bunch of cylinders like in my example.

My example shows how you might get there using Boolean operations and simple closed solids - there are other ways, and I recommend spending some quality time with the tutorials on the page I linked above as well as here asking questions, BUT, please don’t wait till the last minute and then ask ‘How do I use Rhino?’ It is too complicated for that - make your questions narrow and clear, and you’ll get tons of help here.

-Pascal

Hi Pascal,

I’ve been looking through some forums and it seems like I’m experiencing some problems that other people have had too. I’ve been trying to make a curve so that I can revolve it and make 1 complete surface that is both the head and the handle of my vacuum cleaner. To see how it works, I’ve tried to offset the surface of my original document but the surface keeps disappearing completely when I do that.

Also, some edges on the original document are going to have to be naked edges because they won’t connect to something. An example of this would be the curved part at the front that I’ve used the wirecut function on. The nose (intake port) is a separate piece and will attach around that particular wirecut curve. I don’t know if, when I offset the surface to make it thicker, it won’t show up as a naked edge or not.

Any ideas?

Kyran

Hi Pascal,

I really need your help. I need to get rid of some naked edges. Some somehow don’t attach and I don’t know why and some come up with a joining tolerance that I’ve clicked ‘Yes’ on many many times and the edges don’t want to connect. I’m running out of time fast…PLEASE HELP.

I’ve used your idea of revolving the sphere and handle. I don’t know how you had them in one object in your design, but I’ve given it my best shot considering I’ve only used this program for a few weeks. I’ve tried to get rid of the naked edges along the way, but some I know for a fact will have to be naked edges such as the ears because they won’t connect to anything.

I know you’re probably very busy with giving guidance to other users, but I’ve been stuck on this 3D design stuff for a long time. It would be great if I could use some more of your guidance to get over these final hurdles.

Kind regards,
Kyran