Go Back   AC3D Forums > General > AC3D General
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
Old 14th November 2005, 09:07 AM   #1
davidbird
Junior Member
Junior member
 
Join Date: Nov 2005
Location: UK
Posts: 5
Default Holes in Objects

I am new to AC3d and am finding it difficult to put a hole in an object.
The "Make Hole" seems to put a hole of the same shape as the object ie a % of the object
ie a square hole in square object and round hole in a round one.

Can any one tell me how to "drill" a round hole into an Object of whatever shape
davidbird is offline   Reply With Quote
Old 14th November 2005, 01:47 PM   #2
Stiglr
Senior Member
Professional user
 
Stiglr's Avatar
 
Join Date: Feb 2004
Location: Portland, OR
Posts: 604
Default

"Make Hole" uses the shape of the surface itself to base the hole on, and you set the % of the area that makes up the hole.

If you want a different shaped hole in a particular object or surface, you may have to rely on a Boolean operation to do this. It's "messy" and might not be worth it for you, but basically...

1) Create a poly in the shape of the hole you want,
2) Extrude the poly
3) Position the new "cutout" poly such that it intersects the item you wish to create the hole in, and assign both two-sided surfaces.
4) Do a Boolean subtraction, B-A, using the "hole-shaped item" as A and the item you wish to create the hole in as B; set the Boolean subraction to NOT save the original items. (Remember, if it doesn't work the way you want, you can Undo the operation [or change the operands] until you do get it right).

After you perform the Boolean, you may have to do a LOT of cleanup of inadvertent leftover polys, and stuff on the "inside" of the object. Booleans can also cause the creation of new polys and triangles around the edges of a hole that are, to put it mildly, inefficient. For these reasons alone, it might be better for you to use "Add vertice" operations on the surface to manually "outline" the area you wish to cut out of an object, then delete the area. You might even use an intersecting object (as outlined above, stopping short of doing the boolean) as a temporary guide to help you accurately place the new vertices for a manual cut.
__________________
Flight Sim Project Contributor

My Gaming Rig:
i5 2500K Quad-Core CPU at 3.3GHz
MSI P67A-C43 mobo
4GB of PC12800 DDR3 memory
Windows 7
1GB Galaxy GeForce GTX550 Ti video card GeForce 270.61 drivers (4/2011)
Cougar joystick/throttle combo
CH Pedals
Stiglr is offline   Reply With Quote
Old 14th November 2005, 02:51 PM   #3
Dennis
Senior Member
Professional user
 
Dennis's Avatar
 
Join Date: Jul 2003
Posts: 899
Default

Stiglr is right on track here --- Andy also posted a visual tutorial on making a round hole in a rectangle:

http://www.ac3d.org/forum/viewtopic.php?t=1012
Dennis is offline   Reply With Quote
Old 15th November 2005, 05:53 AM   #4
davidbird
Junior Member
Junior member
 
Join Date: Nov 2005
Location: UK
Posts: 5
Default Holes in Objects

Great, Thanks for the Help Dennis and Stiglr.
Its good to get such a prompt helpful reply.
Keep up the good work
David
davidbird is offline   Reply With Quote
Old 20th July 2015, 05:15 PM   #5
jleslie
Member
Expert member
 
Join Date: Feb 2012
Posts: 58
Default Re: Holes in Objects

Quote:
Originally Posted by Dennis View Post
Stiglr is right on track here --- Andy also posted a visual tutorial on making a round hole in a rectangle:

http://www.ac3d.org/forum/viewtopic.php?t=1012

is this available? how can I drill a bolt hole in a cube? I don't want the hole to go all the way through the cube. and I also want a hole all the way through the cube.
jleslie is offline   Reply With Quote
Old 20th July 2015, 06:07 PM   #6
jleslie
Member
Expert member
 
Join Date: Feb 2012
Posts: 58
Default Re: Holes in Objects

this is driving me crazy. how can I drill a drainage hole through the all the surfaces? the cylinder represents where I want the hole to go. I made the fins rack with the polygon tool and then extruded, and the cylinder is the circle polygon and then extruded. I set the tools to object mode, then I click on the rack, then I add the cylinder, and then I do object->boolean-> subtract, but its all messed up. Whats the right way to do this?
Attached Thumbnails
Click image for larger version

Name:	sandie_plant_Image1.jpg
Views:	173
Size:	209.8 KB
ID:	3274  

Attached Files
File Type: ac sandie_plant01.ac (12.7 KB, 167 views)

Last edited by jleslie; 20th July 2015 at 06:09 PM.
jleslie is offline   Reply With Quote
Old 23rd July 2015, 05:58 AM   #7
Andy
Administrator
Professional user
 
Andy's Avatar
 
Join Date: Jun 2003
Posts: 4,563
Default Re: Holes in Objects

From looking at your result in AC3D, it appears that some of your surfaces are facing the wrong way.

I can tell this by setting all surfaces to 1S (single -sided) and looking around the object. If surfaces 'disappear' then they are the wrong way around.

For booleans to have any chance of working, you need to get all normals facing outwards on all objects used.

To fix the original, select one surface (that you know is facing correctly), and use Surface->Unify-normals.
Andy is offline   Reply With Quote
Old 23rd July 2015, 08:58 AM   #8
jleslie
Member
Expert member
 
Join Date: Feb 2012
Posts: 58
Default Re: Holes in Objects

Quote:
Originally Posted by Andy View Post
From looking at your result in AC3D, it appears that some of your surfaces are facing the wrong way.

I can tell this by setting all surfaces to 1S (single -sided) and looking around the object. If surfaces 'disappear' then they are the wrong way around.

For booleans to have any chance of working, you need to get all normals facing outwards on all objects used.

To fix the original, select one surface (that you know is facing correctly), and use Surface->Unify-normals.
THANK YOU!!!! so the normals make a difference! I had no idea. Let me play with that and see;If I can get better results.
jleslie is offline   Reply With Quote
Old 24th July 2015, 11:30 AM   #9
jleslie
Member
Expert member
 
Join Date: Feb 2012
Posts: 58
Default Re: Holes in Objects

Andy,

It worked! thanks again. I was able to make the exact drill hole I wanted. I am confused about the exact layout I needed for the surface face though. as shown in image1 in the yellow circle. I had to have the surfaces of the cylinder from 9:51 to 5:30 facing outward, and from 5:31 to 9:50 facing in to get it to work. I did it by trial and error, but is there a more logical way to decide?
Attached Thumbnails
Click image for larger version

Name:	hole_acd_Image1.jpg
Views:	173
Size:	257.7 KB
ID:	3278  

Click image for larger version

Name:	hole_acd_Image2.jpg
Views:	170
Size:	183.3 KB
ID:	3279  

jleslie is offline   Reply With Quote
Old 27th July 2015, 07:43 AM   #10
Andy
Administrator
Professional user
 
Andy's Avatar
 
Join Date: Jun 2003
Posts: 4,563
Default Re: Holes in Objects

All surfaces should face outwards - that way, the boolean operations know what's 'inside' or 'outside'.

You should probably check the result more carefully. Switch it to single sided and you may see holes where the cylinder surfaces that were wrong touched the main object.

You might want to check the objects for leaky surfaces before you do the boolean too. Any holes, even if they are hard to see, can cause problems with the boolean ops.
Andy is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -4. The time now is 07:44 AM.


AC3D Forum
(C) Inivis Limited 2020