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I'm starting to get into subD and I want to create a try to hold some product.  I have it mostly modeled out and I like the curvature of the model with the sharpness at 50%, but I'm getting some pretty jagged corners and I'm not sure how to address these.  Any input would be helpful.

tray.fmz.zip

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Just a quick glance tells me it's all those triangles in your mesh.

In general, I try to avoid them in favor of 4 side polygons.

I am slammed today but tomorrow I might get time to fiddle with it.

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You can try increasing the number of Iterations to 5 or 6.  

 

Ultimately, You will need to rework some of the geometry modeling though.  The base has some very strange corners and they will need to be rebuilt front scratch before you can get nice smooth corners.  

 

Looking at the model, I wouldn't necessarily use SubD for this.  You can get nice smooth results using solid modeling, and controlled rounding.  

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yeah the base is where I'm having the problems.  I'll rework the cage model so get some better results.

 

I tried creating this shape with NURBS but SubD seemed to be a much faster alternative.

 

This tray is going to be made with a mold and vacuum-formed plastic so I don't think controlled rounding is going to give me the "flowy" appearance that I want.

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I am 100% certain your problems are caused by the triangulated geometry.

I realize that in a couple of the sub-d tutorials FZ shows using triangles,

but I never use them for 2 main reasons:

 

1. They tend to cause “pinched” geometry (especially on corners and edges).

2. You can’t sub-divide triangles any further, so you essentially paint yourself into a corner.

 

I have attached a little guide that I did for one of my co-workers, to help them understand what

causes triangles and how to avoid them. Maybe it will be of help to you.

 

post-209-0-50087000-1525260392_thumb.jpg

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FZnoob is correct that you need to be aware of the number of sides in your faces, however what is most important is to avoid having faces with more than 4 edges. At its heart subD's can only work with triangles and quads so formZ has to breakup the model to handle any faces with more than 4 sides. This gives you very little control with what happens with these faces. Its better to clean the yourself to get predictable results. Note that sometimes face may look like it only has 4 sides, but if an edge of an adjacent face touches an edge of a give face forming a "T" intersection, then the that face will have and additional point to maintain the connection. This is the case with the "large angled face" of the model. (see attached).

 

Here is what we did with your model to get better results:

 

1. We noticed that you have some probably unintended unclean intersection at two of the corners. We cleaned this up with the Delete topology tool (see image).

2 .We used the object doctor to clean up the model some more (extra co-linear edges etc...).

3. We used the insert segment tool (along with the perpendicular snap) to add edges that traverse the "large angled face. Note that these need to "wrap" all the way under the model to the other side to avoid creating a bottom face with more than 4 sides! we just kept inserting segments around the model to get the result using the point and perpendicular snaps.

 

See the attached image for the results this achieved (top line).

 

Once you have the model in clean triangles and quads, you can use operations line the trinm tool with the stitch option to add detail witch will affect the SubD form. In this example we used a plane and the trim and stitch tool to add a line of detail through the model. Notice the effect on the resulting subD! (bottom line).

 

We have attached our model as well.

 

We hope this helps!

post-5-0-14837700-1525272824_thumb.png

post-5-0-05982000-1525272900_thumb.png

post-5-0-39004700-1525272933_thumb.png

tray-tech.fmz.zip

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Sometimes I look back over old posts to pick up a tip or 2. When I found this one, I realized I never did get around to doing a sub d tray.

So I gave it a go this morning. After a couple of false starts I was able to produce this model using nothing but the sub d tools. 

It's a clean mesh with no triangles, which I always try to avoid. 

tray.jpg

Edited by FZnoob

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Funny this came up today.  I was delving into sub-d's today to and was having problems with this shape...

How do you blend a soft shape like the centre bar of this bar with the hard edge parts of the ends of the wrapper ?

 

 

Peanut butter wrapper.tif

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The key to getting good results with Sub-D objects is to start with a simple frame of the desired shape and edges at key edges of the shape. For this shape we made a frame with a single edge at the flat ends. The whole object was given a 60% sharpness and then the end edges and points were selected and assigned a 100% sharpness to make the hard edges.

Screen Shot 2018-10-15 at 5.33.16 PM.png

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22 hours ago, rmulley said:

Funny this came up today.  I was delving into sub-d's today to and was having problems with this shape...

How do you blend a soft shape like the centre bar of this bar with the hard edge parts of the ends of the wrapper ?

 

 

Peanut butter wrapper.tif

I do this sort of thing all the time. If you need some more advanced help let me know.

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On 10/16/2018 at 2:14 PM, FZnoob said:

I do this sort of thing all the time. If you need some more advanced help let me know.

Would your way of modelling differ from Tech's ?

I'm always up for learning how people do things if you don't mind posting

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Tech showed perhaps the most simple way to do it. 

My approach would require a few more steps and some additional geometry.

The end result would be something a bit softer and a little more realistic.

I should have time tomorrow to post a series of step by step series screenshots to get you started.

Once you get the hang of it, you can tackle some more difficult shapes.

Do you happen to have a better image of the wrapper? That would be helpful but not completely necessary.

If you look in the "tutorial" section of this forum you will find a 3 part series I did on sub-d modeling a leather chair.

It might be a bit more than you want to tackle now, but it's something you can play around with if you care to.

 

Edited by FZnoob
add something

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That would be great if you could. Unfortunately thats the best image of the wrapper... I just picked that brand as I share a co-working space with them and wanted to do it up as a test project.  I'll check out your other tutorial though.

 

Appreciate the time and effort!

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Here you go. I did it pretty fast, so I hope it's clear. If you get stuck let me know. It's not difficult once you understand the concept.

Looks like I am going to have to upload it in 2 files due to the size.

Here's pg 1

Candy bar tut pg 1.jpg

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1584029385_Candybartutpg1.thumb.jpg.7df641718fa985afbc4cfb5bf7a3d8d1.jpgHere you go. I did it pretty fast, so I hope it's clear. If you get stuck let me know. It's not difficult once you understand the concept.

Looks like I am going to have to upload it in 2 files due to the size.

Here's pg 1

Candy bar tut pg 1.jpg

Candy bar tut pg 2.jpg

Edited by FZnoob
sorry for the double post.

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Thanks guys. I created a 2 page pdf of this and uploaded it to the "tutorial" section of the forum.

"Candy Bar Modeled With Subdivision"

I hope that FZ sees fit to add a symmetry tool in the future. It would cut the work it half. 

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