Frustrating day with Shapeways/sketchup

Discussion in 'General Discussion' started by steveb2000, Nov 28, 2011.

  1. steveb2000
    steveb2000 Member
    I've been working on a headlight housing for a bicycle project, and after a few designs I thought I had one I wanted - see the attached skp file.

    Resizing added a few stray lines that weren't there on the larger size drawing, but it still looked ok.

    But when I upload it I get this

    https://www.shapeways.com/model/393732/bracketlight2arsz.html ?key=c2c3fbb8f00a81cb5afff2b054461a5b

    <a href="https://www.shapeways.com/model/393732/bracketlight2arsz.html?key=c2c3fbb8f00a81cb5afff2b054461a5b" target="_blank"></a>
    it looks like the outer frame has been deleted and the front somehow connected to the interior which has been made solid.

    An earlier design had random sections removed, and I only noticed it when I viewed it in the 3-d view as it was screened.

    I don't have much for ideas to fix the drawing, Sketchup hasn't been particularly cooperative or stable, even drawing stuff 12x size and resizing since it does poorly with smaller objects.

    I'm guessing I'll have to get meshlab? So it's draw in sketchup, export, modify again in meshlab, import, export, upload? 3 programs 3 file formats to do one job?

    :(


    Sorry for venting a bit, I'm a couple months into this, and I could have made a few of these in a lot less time than I've spent relearning the computer drafting and trying to learn the workarounds for problems the system I learned on 25 years ago didn't have. (CADDS4 simulator and Cam Apt snap Draft if there's any oldtimers here) My idea was to use a combination of new and old technologies, but right now that's looking less possible and more like it will be all old tech.


    Steve
     

    Attached Files:

  2. don't be discouraged. i am not familiar with these programs that you stated but i thought that i was an old timer when i look on autocad 12 with fondness...

    i would try other programs too. i prefer Blender 3d but there are several others that might be more your speed. including 1 or 2 that are browser base.

    lastly- although sketchup is a pretty robust program every time i see a posting it is because someone is having a problem. i think that it was never fully realized as a program that you could print from...

    chris
     
  3. steveb2000
    steveb2000 Member
    Thanks Chris.

    I'll give Blender a try. Looks like it does a lot!

    I think sketchup problems may also be related to expectations, at least for me. When they call something a drafting program I think technical drawing which it doesn't seem good at. It occurs to me that most of the tutorials lean towards rough architectural rendering. I haven't tried doing that, mostly because it's quicker to do freehand.

    The two systems I learned on were done in by Autocad. I got a certificate for cad/cam in 86 and first saw Autocad in 87 when I went back to look into transfering a course or two to complete an associates degree. I'm thinking it was either version 2.6 or 9. What a revelation. Only a year before on a field trip we'd seen a system doing 3d of sorts but the cost was amazing, $50,000 for the workstation plus 120-160000 for a small mainframe. Seeing Autocad doing all the same things on a PC was amazing. I eventually went into industrial machinery repair rather than drafting.

    Steve
     
  4. Youknowwho4eva
    Youknowwho4eva Well-Known Member
    The problems I've seen a lot of sketchup users have are inverted normals, and Items with overlapping faces. Make sure that you don't have items that sit next to each other, embed them into each other a little, and shapeways will automatically join them. For your inverted faces, I'd check out NetFab basic, as I've read it has tools to fix these, and it can scale your model as well.
     
  5. lensman
    lensman Well-Known Member
    No, for your sanity's sake, DON'T. If you're having problems with SketchUP you're gonna want to top yourself with Blender. As significantly improved as the programme is it still is not EASY to use. Heck of a lot better than it was a few years ago, though.

    Take a look at GroBoto. For its price, US$100, this is a great little modelling programme that is quite easy to use. The Boolean tools are fantastic. And for anyone who has only used older versions of GroBoto please don't comment until you've tried version3 - It's like a whole new programme.

    Another fun one to use is Autodesk's 123D - and it's FREE !

    As for your comment about using 3 programmes to get the job done.... I and many others will often use 4 or 5 depending on what we're modelling...

    Glenn


     
  6. i like BLENDER!

    but you are right- it can drive you batty if you let it.

    i can tell you why i choose blender though.

    it is a one stop shop.
    as far as modeling goes- i can model something in blender and export a shapeways ready model straight away. no fuss no muss straight away. but i also like that i can do all of the other artsy stuff that i want in blender too without paying out the nose. for instance i use Max at work and there is a lot of cross over what you can do on each program but at home i do not have the couple of grand it takes to get a license... blender is the closest that i have found that will do the job.

    i have also used lightwave and autocad in my 3d exploits and in limited amounts Catia, Unagraphics and Deep exploration and all of the programs have one thing in common- they are expensive...

    i did look at 123d and that seems to have a huge upside and could potentially be exactly what you are asking for.

    i have never seen groboto but it looks very cool indeed.

    chris
     
  7. lensman
    lensman Well-Known Member
    I knew that response would elicit something from the Blender fans out there!

    You're absolutely right in that it is a one-stop programme - and it is free as well, I forgot about that. When I took a look at the short animation movies that were made with Blender they just made my jaw drop! Incredible stuff.

    Probably at the root of my frustration with the programme is that fact that I use so many programmes and then to have to try and learn another - It was sort of like learning to fly a Jumbo when all I wanted to do was travel 10 miles!

    I do marvel at the dedication and work that goes into that programme from all at the Blender Foundation.

    Glenn
     
  8. steveb2000
    steveb2000 Member
    Ok, looks like I'll have to try a few different ones.

    So some of you use multiple programs routinely for different parts of the same drawing? Interesting....

    Much of what I'm trying to do is pretty simple as far as the shapes go, and I'm not especially picky right now about the smoothness of curves etc.

    complicating things is learning the new stuff during the toddlers naptime.

    Ease of use is a tough one, so far the stuff I've done is.

    sketchup - Easy to learn, hard to understand why it does some of the odd stuff it does. And odd in what it can and can't do.

    snap draft - really easy to use, but not 3-D. I did a lot of my stuff in isometric view which is similar. very simple menu choices and easy direct entry of sizes, and with creative use of some features certain things were very quick. Frame for a smallish house took < 30 minutes and it generated the materials and cut list.

    Cadds4 - Not really easy to use, more like writing a program to draw a picture. The simulator was MATC cad, it had a function for drawing elipses, which oddly sketchup doesn't have. Using the digitizer pad wasn't really accurate, but the coordinates could be entered directly - like " ins line x3.125y0z0 to x3.75y2z3" (Not sure I got the syntax exactly right, but it has been 25+ years)

    Thanks for all the input. with the time constraints I have it's good to get input from someone at the other end of the learning curve. The first time I had more time to learn, but it was pretty much new to everyone.

    Steve
     
  9. Hi Steve,

    There's no reason to use anything but Sketchup for this model, especially since you've got this far. I use Sketchup for all my 3D printed models, and always recommend it for beginners. It works great for any mechanical part like your bracket. (Organic and colored models are more easily created with other packages.)

    One reason that you see so much garbage made with Sketchup is because its free and relatively easy to use, so many people start modeling something, and give up when it gets a little difficult. Blender's different because (if you're like me) you download Blender, open it up, and give up before even making a cube! :blush: :laughing:

    Anyhow, I took a look at your model, and found a few problems commonly made by beginners - Inverted normals(aka reversed faces) and extra interior edges/faces. These are easily fixed if you know what you're looking for.

    So hang tight, and I'll walk you thru this step-by-step - no need to learn another program!

     
    Last edited: Nov 29, 2011
  10. The first thing I noticed is the two different colors on your model. This indicates reversed faces, which confuse the 3d printers. Here's a picture of what I mean.
    [​IMG]
    A correct model will show white faces only. To fix this, Right click > Reverse Faces.

    Then, I triple-clicked the model to select it all, and made it a group. I do this because Sketchup will tell me when the model is "Solid" in the "Entity Info" dialog. "Solid" means that the model is a closed shell, with no extra interior lines or faces. Think of your model as a mold for the 3D print material with nothing inside to interfere with the printing process.

    When I group your model, its not solid, so I search for the problem. To make quick work of this, I use the Solid Inspector plugin. Solid Inspector highlights a number of problems, shown by the colored circles below.
    [​IMG]

    To fix these problems, I open the group and Cut (Edit > Cut) a large face near one of the highlighted problems to let me see inside. Here I can see a couple extra faces (Marked in red by me for this illustration) that are causing the model to be non-manifold.
    [​IMG]
    I assume you understand why these need to be deleted, if you don't, just ask.

    Here's an 'after deleting internal faces and reversing faces' pic:
    [​IMG]

    Simply paste the cut face back in place when finished: Edit > Paste in Place.

    ...to be continued...
     
    Last edited: Nov 29, 2011
  11. steveb2000
    steveb2000 Member
    Thanks! That's all really interesting. I'd assumed the leftover construction lines that were internal didn't actually matter as long as the exterior had no gaps.
    I'll get that plugin for sure if it works with the free version.

    I'll have a few general questions, but I'll save them for the end.

    I'll probably learn the others anyway. I've already installed blender and 123D and it looks like they do things very differently than I'm used to.

    What a learning curve! going from a pencil to the early systems was pretty easy this isn't so easy.
    Either that or I've gotten dumber over the last few years.

    Steve
     
  12. Yes, that plugin works with free Sketchup. I gotta run for a while, but plan to post back here in a few hours.

    Cheers,

     
  13. no worries...

    i originally learned on a board, but i have been doing this for so long that i don't know if i could ever go back. added bonus- my penmanship is impeccable.
     
  14. lensman
    lensman Well-Known Member
    Ahahahaha, definitely been there! :laughing:

    Great SketchUp instructions, by the way. Learnt a couple of things myself.

    Glenn

     
  15. Glad this helps some of you guys :)

    Another thing you can do to help pinpoint problems is to soften the curved edges. Just Right click the group > Soften/Smooth Edges and set the slider to around 25 degrees. Wherever you see a crease that doesn't look like it belongs, there is likely an internal face that needs to be deleted.
    [​IMG]

    If you cut away some of the outside faces like I showed previously, you can see all the internal faces that need to be deleted.

    Steve, I'm unsure what the center open part of your object is supposed to look like now. If you don't mind the extended lesson, could you clean the model as best you can now and post that model back here?

    I'll take it from there and show you how to make the intersections/boolean cuts in the next step.

     
  16. steveb2000
    steveb2000 Member
    yep, I'll do a bunch of cleaning up on it and repost.

    That section shown will have loads of internal faces. I do the inner half dome then the conical inner roof then repeat for the outside part. The fins I did after, and then removed the planes inside the interior, but not the ones inside the roof.

    I haven't had much luck using the follow me function to draw partial domes, so I'm doing them the harder way by drawing arches and connecting them. Lots of extra layout lines.
    Deleting them often deletes a face I want, and sometimes it's hard to get that face to come back.
    The reversed faces thing is interesting. I've wondered why sometimes the face is white and sometimes gray/blue.

    The bracket section was it's own drawing, and seemed to upload just fine. I think I'll clean that up too before I have it printed.

    Steve
     
  17. i knew there was one i was forgetting... take a look at tinkercad

    let me know what you think.
     
  18. steveb2000
    steveb2000 Member
    Looks interesting.

    Operator error setback today. Did lots of fixing and decided to redo one of the really messy areas. Except I did it on the resized version.

    Sketchup REALLY does not like small things.

    so I'll have to redo the fixes on the large version.

    Ah well, lots of good practice

    Steve
     
  19. Keep working Steve, you'll get there. :)

    I'm following along, and will jump in with more help later.

     
  20. steveb2000
    steveb2000 Member
    The mistake yesterday was thinking I'd just have to remove some excess internal faces. So I did it on the resized version, which I knew wouldn't accept much redoing. After fixing a bunch of stuff I tried redrawing one section. Which made things much worse.

    I had really a lot of excess lines and planes inside leftover from the drawing. I cleaned off some of the surface lines that weren't needed too.

    Lots closer now. Un resized attached, only a handful of problem areas left. It's hard to see what's wrong with most of the remaining ones.

    I'm very thankful for all the help and support from everyone.

    Steve
     

    Attached Files: