View Full Version : Help With Topology

07 July 2010, 06:02 PM
Hi, I've been trying to model this sander, but can't get the correct topology to hold its shape(square part) once it's smoothed. The pic is of the basic form blocked out. Was wondering if someone with more experience would mind helping me with the proper topology flow that would keep the square part that's connected to the cylinder base from collapsing when I smooth.


07 July 2010, 06:57 PM
Hi, I just wanted to show more examples of the problems that I'm having. Could not find a way to work out the triangle along the edge either....


07 July 2010, 07:28 AM
I played around with some ways of creating that pinch and here are my ways of doing it. I tried to keep it looking as close to the sander as possible, although its still way off.

heres a paint over, i hope it makes sense.
heres my result (divided 2x when smoothed):

07 July 2010, 02:35 PM
Thanks again for the help. I'm gonna play with the ideas and see what I can come up with.

I appreciate it.

07 July 2010, 07:50 PM
You have a couple edges that aren't there when its not smoothed that are when it is which makes me think you have a couple extra edges holding verts together and nothing more. This may just be the software you use though making me think this as I see faces with more than 4 verts...seeing as I don't/can't make faces with more than 4 verts I've know way of knowing if the program would add these connecting edges in for you or not. You also have verts with more than 4 edges. On flat areas I can pull that off and make it look meh...but I haven't found a way to make it look good if I put verts like this near/in areas where I want a lot of control as the loops already in place are usually jacked.

I've edited your pic showing you what I mean. The lowest circle numbered 1 shows an edge that isn't there when its not smoothed. The upper circle with a 1 was another edge I thought was like this as well, but looking closer its more than likely that unsmoothed this other edge just adds to the circle numbered 2

The other thing that will help you is if you take a look at Dare's model at the spot your asking for help on you'll see he has 2, from what I see, loops (I call em controlling loops but Ive heard a couple other words for it so you might not know em by that word) that is making that edge sharper...loops that are missing from your wire. Some people do this with beveling, and it does work most of the time, but throwing in an extra loop on both sides of the edge you want to be sharp will give you a bit more control then just beveling in my opinion. Again this might just be the app your using using some type of optimization to avoid showing edges it doesn't have to..I dunno. With those verts that have more than 4 edges, though, you can't put controlling loops there because the edge flow looks like its going the wrong way. Lowering the number of edges coming off of those verts will make it easier to control the flow.

I've been teaching myself 3d modeling with blender for about 4 years now so take this for what its worth...a noob letting you know what I'd think would create what you wanted, given what you have, if this where my model modeled in blender. There's a good chance I didn't word it right, got it wrong, or misunderstood the problem.

07 July 2010, 02:41 PM
I think the part that you're talking about is apart where I had a triangle that I couldn't get rid of without the typology effecting the shape.

I'm using maya. This piece looks simple enough to model, but it's trickier than it looks. Give it a shot maybe you can show me a better approach.

I appreciate your input and I'm still working on it.

07 July 2010, 01:20 AM
if you give me the make/model of the sander so that I can grab some reference and I'll give it a go for you.

07 July 2010, 04:13 PM
I gave it a shot using your references. I get better understanding holding the object in my hand but meh I was bored and decided not to wait on model number before giving it a shot :D

What I've said can be seen in the image I'll provide below as well as in the image provided by your other helper. These controlling loops where you want this detail should help you get it.

If I had spent more than 5 minutes on this example, the detail would be more apparent. I think its good enough as is to give you an idea about what I mean without showing a bunch of loops that do nothing but aid the loops creating form. If not let me know and I'll rework my wording or the example.

Using a similar flow you can achieve the same thing I and your previous helper have. Besides the extra resolution added in his example you'll see the flow is very similar. Even to the point where he has a 5 pole and 3 pole in similar locations to mine causing our flows to go similar directions, directions I think are needed to create the look you're going for.

A bit more time would make it look prettier as would increasing the number of loops. The more loops you have in between your controlling loop and the nasty way that loop could go the better, in my opinion. Of course this doesn't mean I think you can go crazy with that. To many loops, especially to early in the modeling, make flow control a pain.

I think the part that you're talking about is apart where I had a triangle that I couldn't get rid of without the typology effecting the shape.

I had similar triangles further along the body when I modeled the "complete" object, prior to deleting what was uneeded to show you this example. The vert with 3 edges has one edge that curved down and to the left around the body of the sander. The very next vert (which was deleted) was 1 of three that formed a triangle in order to keep quads along the side of this groove that gets deeper the farther it gets away from this detail.

If you can visualize this deleted vert you'll see how the edges that were not deleted seperated the two areas of detail. My triangle was not incorporated into the detail I was trying to achieve in this spot. Instead it only affected the shape I wanted it to. Verts from your triangle share an edge with the verts your using to create this detail thats giving you issue. This creates unwanted tension, I say unwanted because you say the only reason for this triangle is to help with the form of another spot. Seperate it with another loop, or two, and the tension will ease a bit. With less tension it will be easier to control the shape you want. Redirect some of the flow and that shape will be even easier to control.

This piece looks simple enough to model, but it's trickier than it looks.
Most of the time the way we look is the only trick involved, ask a magician...or a professional artist :arteest: . Usually looking at it in a different "light" will let us see the bottom of the bottomless pit. Keep chugging along. When in doubt...stand on your head.

07 July 2010, 05:44 PM
Thanks for all the feed back.... Here are some of my examples. I like the shape, but my typology still sucks.... I'm going to work on cleaning it up later. The model number? It's a Porter Cable sander. Model number 333_5" random orbit sander. I'll also try to take some better pix.


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07 July 2010, 05:44 PM
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