topic Re: Need help creating a specific object. in AutoCAD Forum

Need help creating a specific object.

Anonymous — Fri, 09 Mar 2018 00:37:09 GMT

Hello Cad-o-sphere.

I need some help creating these "vent holes" on my trashcan desktop PC. I posted a picture in this forum. Only difference is, my computer is a cylinder, rather than triangular.
You can see the vent holes right below the mushroom.

What I've done so far in my design is this: I created a cylinder, added a circle inside of it, extruded it downwards, and used the subtract function to bring the interior of the cylinder down (think of the apple pro desktop). Now, my next step is fabricating the vent holes, as you see in the image below. And placing them within the subtracted cylinder.
I tried making a "cone" so I can attempt that downward slope, and adding the vents holes. That's the part that I don't know how to do.

I hope my "meh" explanation can get across to you folks. I'm sure most of you can tell me how to do it in a matter of minuets.

Re: Need help creating a specific object.

john.vellek — Fri, 09 Mar 2018 01:55:04 GMT

Hi @Anonymous,

From the picture, it appears that you can make rectangular boxes (3D solids than you can push into the computer body and then subtract. Does that make sense? Can you share your model thus far?

Please select the Accept as Solution button if my post solves your issue or answers your question.

Re: Need help creating a specific object.

WarrenGeissler — Fri, 09 Mar 2018 04:15:40 GMT

I took your idea and kept going. Similar to what @john.vellek said about using boxes - if your peripheral slots are in a slotted area of your cylinder this is how I would do it. Instructions are in plan (TOP) view.

Re: Need help creating a specific object.

Anonymous — Fri, 09 Mar 2018 05:00:05 GMT

Here is the model I have so far. As you can tell, I'm simply designing a model, rather than making a full out computer, layer by layer (my autocad experience is no where near good enough to do that.)

As you can see, that cutout in the center is where I'd put slightly downward bending vents.
The "pancake" you see to the side is going to slightly mirror the HP wave that you saw in the original image I posted. I'm going to add a downward "cone" that goes into the middle of the vent (ala the HP wave you saw in the last image).

Only difference is, my design is useful, rather than useless 😄

Only if I was good enough at AutoCAD to design the inside/outside of the computer, alas....I am not.(thinking of using illustrator to make a fake mock up of the inside of the computer)
Anywho, image is posted! Teach me your ways, you autoCAD wizards.

Re: Need help creating a specific object.

Anonymous — Fri, 09 Mar 2018 05:36:39 GMT

I'm sorry, I don't understand the context of what you did in the file?
It's a circle with a little square edge of it chopped out...?

*Again, maybe you're explaining something simple a more experienced user would know*

Re: Need help creating a specific object.

WarrenGeissler — Fri, 09 Mar 2018 16:17:30 GMT

From left to right is the progression to help you get started. Look at it in 3D - SE ISOMETRIC VIEW. Start with a cylinder (like you did) and subtract another cylinder (like you did). Then based on the image you posted you need the peripheral plug-ins in a cut-out. I created a triangular shape and extruded it for the cut-out, then subtracted it from the original solid thus forming your cut-out shape. Zoom in at the bottom of the cut-out and with DYNAMIC UCS turned on you can draw your peripheral plugs directly on the face of the cut-out. I drew a guide-line so you can align your plug shapes. You can then use PRESS-PULL to push the shapes through your cylinder thus creating the holes needed for the peripheral plugs.

Re: Need help creating a specific object.

Kent1Cooper — Fri, 09 Mar 2018 19:50:36 GMT

Also consider the option of not "creating the holes," but rather making the ribs [or bars or whatever you call them] between them. Make one as a simple Extrusion, do some Copying and/or Arraying, and some Slicing of the excess off the ends outside the perimeter, to get one segment's worth, and then Mirror and/or Array around the whole shape.

Re: Need help creating a specific object.

john.vellek — Mon, 12 Mar 2018 17:48:03 GMT

Hi @Anonymous,

Warren has put in some time to help you with this process. Have you been successful in creating your model? Or, are you still running into some roadblocks?

Please let me know the status of your project and if you need any additional resources.

Please select the Accept as Solution button if my post solves your issue or answers your question.

Re: Need help creating a specific object.

john.vellek — Thu, 15 Mar 2018 20:27:14 GMT

HI @Anonymous,

I haven't seen you come back to the thread and I was worried you were having problems with the steps.

I decided to start an example using @WarrenGeissler drawing.

I created the geometry for the vent holes using a polar array.
I then created the top with a thickness and used loft to create the conical shape
I copied and rotate the conical shape 180 degrees to form the base of the top
I then used presspull on the vent geometry to give it some height
I moved this new collection of solids into the conical base part and used SUBTRACT. This gave me vent hoes in the "conical" base
I then used UNION to join the top and bottom of the top and moved the resulting solid to the computer base that Warren had already created.

I attached my version (where I copied each step) so please take a look and let me know if this process works.

Please select the Accept as Solution button if my post solves your issue or answers your question.