Autodesk 123d is one of many freely-available apps that new MakerBot users might consider learning.  And unlike some other programs we love, it looks like Autodesk wants it to be easy to print your models on a MakerBot.  In fact, they want it so much that they’ve just posted the above video on their youtube channel.

It’s a bit long (over 9 minutes) but put it on your list for when you’re woodshedding your 3d-modeling chops.  While it’s specifically aimed at the Thing-O-Matic, most of what they’re saying should transfer to the Replicator.  Just model for a larger build area!

123d is a bit different from other modeling programs, and might be a bit counter-intuitive if you’re used to one of the others.  However, their youtube channel has a number of tutorials and there are some neat things about the project (like an iPad app and a photo-to-model program.)

If you’re looking to pick up some 3d modeling skills while you’re waiting for your Replicator, this is one of many great programs to learn!

Parametric Boltless Hook for keyhole shelving units by Timmytool

As I’m gearing up for Thing-A-Day this year, I thought others might be interested in more OpenSCAD tutorials. ¹  Is there something you would like me to cover in another tutorial?  What would you like to learn?

While I’ve more or less written these tutorials right up to my level of competency, there are a few additional things that we could cover – some of the additional variables for previously covered functions, hull, Minkowski, and for loops.

OpenSCAD Tutorial Series

1. OpenSCAD Basics: The Setup
2. OpenSCAD Basics: 2D Forms
3. OpenSCAD Basics: 3D Forms
4. OpenSCAD Basics: Manipulating Forms
5. OpenSCAD Intermediates: Combining Forms
6. OpenSCAD Intermediates: Mashups
7. OpenSCAD Intermediates: Modularity
8. OpenSCAD Intermediates: Extruding 2D Objects
9. OpenSCAD Intermediates: Fixing Design Problems

Parametric Boltless Hook for keyhole shelving units by timmytool

Turn the unused keyholes in boltless shelves into practical hanging space. Using 2 keyholes in the uprights this thing sits and provides a hook for things like scissors, headphones (I use 2 half shelves and a laminated MDF as a PC desk, huge desktop), pots and pans and a whole thingiverse of items. Make your own custom 3d prints that are held up with this print. Yes it’s completely parametric so it will work with any brand of keyhole style boltless shelves The bridge in the model might sag, as long as it minimal it should add to prints snug fitting. (Yes it works better without a perfect bridge) Some of the pics are of the non parametric version; it has a smaller wedge in the hook but otherwise is near identical to the openSCAD’s uploaded stl

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1. As always, if you go through these tutorials and publish something on Thingiverse, I’d love to feature your designs in my OpenSCAD tutorial posts!

Three reptilian skulls

I was inspired by the dinosaur skull posted on Thingiverse and set out to look for more. The Digimorph project at the University of Texas has some dinosaurs, but the STL files are not posted.  However, Artect, a company that makes 3D scanners, has posted a very nice high-resolution STL file of a Tarbosaurus skull, on their 3D model download page. It’s the first model listed on the page.  I sliced it in Netfabb, and have posted the sliced files on Thingiverse.

Keep reading for some tips on how to print this object, and other complex organic shapes!

To print the Tarbosaurus, I first sliced the skull into 4 sections using Netfabb, using the same procedure I have posted about earlier on this blog, to print a crocodile skull. The key is to choose your slices in such a way that you don’t end up with too many hanging pieces, and also to reduce extreme overhangs.

Tarbosaur skull, assembled

There was really no way of printing this without extensive support, so I enabled support material in Skeinforge. However, I did not want a raft, since I wanted a very flat mating surface when I glued the finished skull together. To use support material without a raft, go into the raft settings in Skeinforge, and set the base layers and interface layers to 0.  You can then enable raft and support when generating G-Code, but no raft will actually be made. (Raft has to be enabled for support material to work).

For the raptor skull that is also posted on Thingiverse, I did the opposite. It looked feasible to print without support, but the very long and narrow pieces of the jaw print straight up a long way, and I was concerned that they would not adhere to the build platform. For this print, I enabled raft (setting base and interface layers to 1) but not support.

The default support options are very sturdy - unnecessarily so. The parameter that controls the density of the support material is hidden away in the raft module in Skeinforge, it is the Interface Layer Density (ratio) parameter. Reduce it to 0.4 or even less. Making this number smaller will make the support material flimsier, and easier to pull away from your model.

I have found it helpful to raise the extrusion temperature to 235C. This makes the ABS less viscous, and helps it to stay flat once extruded. Otherwise, some of the overhangs will curl up, and snag the nozzle as it travels back forth.

Once printed, you’ll notice that pulling off the support materials leaves white “bruising” on the ABS. In fact, any kind of trimming or shaping of the ABS will do this. A great remedy is to go over the piece with a hot air gun – a second or two of exposure is enough to “cure” the plastic, and magically erase the bruises.

If, like me, your print is not exact, you’ll have to bend it a little to make it fit properly when you glue it together. This places the whole piece under tension, which is not a good thing. Once again, a quick pass with a hot air gun is enough to slightly soften the piece, and relax any tensile stresses. Don’t overdo it – the piece can melt quicker than you think.

I hope this is useful. Please post if you find any other interesting models to print. The Digimorph project has some more STLs available for download, I look forward to hearing about any successful prints!

Dinosaur skull -- sliced and scaled for Makerbot TOM by tonyv

By request, I'm posting the files I used to print the dinosaur skull originally uploaded by cyborg527:thingiverse.com/thing:10447 In plenty of time for Christmas, it's "Rudolph the Red-Nosed Raptor". (I ran out of white...but the red works too, somehow %^)

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Tarbosaurus skull, sliced for printing by gpvillamil

This is the skull of a Tarbosaurus, an Asian relative of the Tyrannosaurus Rex. The scan was originally posted online by Artec, a maker of 3D scanners, on their 3D model download page, artec3d.com/gallery/3d-models/. (Some cool stuff there, by the way.) All I've done is sliced it into 4 pieces using Netfabb, to make it easier to print. The STL from Artec is super clean, so if you have better ideas for how to prep the piece for printing, download their original file and give it a try!

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iPhone dock created in Shapesmith and printed on Thing-O-Matic

How can I model the thing I want to print?

As the population of 3D printer operators continues to grow, answering that question will become more important than ever. Combining parametric modeling and a clean UI, browser-based Shapesmith hopes to provide an open source answer.

The developer, MakerBot operator, and Thingizen Benjamin Nortier tells us all about it.

Q: Who are you and what is Shapesmith?

I’m a software developer with an Engineering background and I’m also a 3D printing enthusiast. Shapesmith is a browser-based 3D modeling tool that I’ve been working on, and am very excited about. It is aimed at users who want to create high-quality parametric models for 3D printing, but who don’t want to spend thousands of dollars on expensive 3D CAD software.

I wanted to design an Unmanned Aerial Vehicle (UAV) after being inspired by DIY Drones. I realised that it would be very attractive to 3D print aeroplane parts and I was using tools like Blender and Sketchup to design some airfoils or wings.

Because I had worked on a 3D CAD tool for electromagnetic simulation earlier in my career, I was very dissatisfied by the free design tools that were available. This dissatisfaction was reinforced when I bought a MakerBot Thing-O-Matic and started to design some models. So I decided to try and make something better.

Q: Why did you decide to open source it under the Apache license?

Two of my favourite open-source projects, Riak and CouchDB, are licensed under Apache. They have vibrant communities and also have profitable businesses around them. I hope that I can build something similar around Shapesmith in the future. Restrictive open-source licenses like the GPL put off commercial users, and the success of Shapesmith will depend on having a good balance between non-commercial and commercial use.

Q: Your technology choices are interesting. Why are you using Erlang and Riak?

And Javascript! I’m a polyglot and I’ve worked professionally in 11 languages, and there is no platform that can hold a candle to Erlang for writing robust, distributed, back-end applications. For example, because of the B-Rep modeling used behind the scenes, the geometry operations will have to be farmed out in future versions to machines with lots of processing power. This is to ensure a reasonable quality of service for many users in the future. This is very easily encapsulated by wrapping the C++ processes inside Erlang processes, and it’s very robust. The choice of Riak is an extension of that desire for robustness and the ability to scale out to many users. Riak is also written in Erlang.

Q: There seems to be a trend in WebGL-based 3D modeling tools: 3DTin, TinkerCad, CloudSCAD. How do you see Shapesmith within this landscape?

Yes, and it’s great for everyone involved. Each has different trade-offs, and I would say Shapesmith is positioned somewhere between CloudSCAD and TinkerCAD – I’m trying to balance the power of parametric modeling (CloudSCAD) and a usable, intuitive interface (TinkerCAD).

Q: The open source desktop modeler, Wings3D, is also written in Erlang. Do you have plans to either collaborate with its developers or to incorporate some of its code into Shapesmith?

Not right now, but there is certainly scope for that in the future. The focus at the moment is the B-Rep modeling and the user interface. Wings3D is a mesh modeler, and mesh modeling can become complementary to parametric B-Rep modeling. This could provide more artistic abilities such as sculpting to Shapesmith.

Q: What can we expect in future versions?

At the moment, the focus is on the storage mechanism for models, and doing it in a way that facilitates sharing between users. The design is based on the way git works, so it will enable users to incorporate and modify models from other users in their designs. This will also enable exporting to Thingiverse and other sites that have upload APIs.

Thereafter, I would like to add 1D and 2D operations, plus extrusions and chamfers. These kind of operations are very powerful, so I will finally be able to design a wing for my UAV!

Apart from that, the user interface will keep evolving to try and keep the balance between intuitive ease of use and powerful, parametric modeling.

Q: How can others contribute to its development?

Shapesmith is on Github where I welcome patches and issues. There are also two mailing lists, one for users and one for developers. I would really like to hear from people about bugs, and about what features they would like to see in Shapesmith.

If you have a WebGL capable browser, you can try Shapesmith now!

Thanks for your time Benjamin! We look forward to seeing Shapesmith’s continued progress!

This guest post is part of Project Shellter

Annelise made an awesome  video that showcases fun things she’s done with sugru in the last few days- we can’t wait to see what our users come up with!

Parametric Involute Bevel and Spur Gears by GregFrost

Today I was trying to design something with one large and one small gear making use of Cbiffle’s awesome Spur Gear Fitter Script and Greg Frost’s Parametric Involute Bevel and Spur Gears script.  Unfortunately, whenever I tried to create a large and a small gear, I always ended up with the small gear having no teeth! ¹²

Cbiffle’s script is really useful if you don’t want to get too deep into the math of making gears, but do want gears with a certain gear ratio that will mesh well.  It basically takes care of all of the math you would normally need to get good fitting gears from Greg Frost’s script.

I asked Syvwlch for advice about my toothless gear problem.  He suggested there was a bug in the Spur Gears Script that would cause gear teeth to disappear in certain circumstances.  His way of getting around this problem was to use a non-integer for the number of teeth!  I tried 9.99 teeth (which failed) and then 10.001 which worked!

Parametric Involute Bevel and Spur Gears by GregFrost

This OpenSCAD script provides modules for both Spur and Bevel Gears. It has some major enhancements over my original gear script thingiverse.com/thing:3534. It uses some of the spur gear nomenclature code from TheOtherRob github.com/TheOtherRob/MCAD with my own code for generating the involute teeth. The bevel gear is also my own work. Thanks also to elmom for some enhancements to my original gear script thingiverse.com/thing:3547. Enhancements include the Bevel gear module, backlash settings, parameterised number of facets for the involute curve and whole of tooth generation to avoid some of the issues the original script had when mirroring a half tooth. The STLs provided are not intended for direct use, but instead show examples of what can be done with the parametric script. Parametric Involute Spur Gears take the following parameters:number_of_teethcircular_pitch or diametral_pitch: controls the size of the teeth (and hence the size of the gear).pressure_angle: controls the shape of the teeth.clearance: The gap between the root between teeth and the teeth point on a meshing gear.gear_thickness: the thickness of the gear plate.rim_thickness: the thickness of the gear at the rim (including the teeth).rim_width: radial distance from the root of the teeth to the inside of the rim.hub_thickness: the thickness of the section around the bore.hub_diameterbore_diameter: size of the hole in the middlecircles: the number of circular holes to cut in the gear plate.backlash: the space between this the back of this gears teeth and the front of its meshing gear\'s teeth when the gear is correctly spaced from it.twist: for making helical gears.involute_facets: the number of facets in one side of the involute tooth shape. If this is omitted it will be 1/4 of $fn. If $fn is not set, it will be 5. Parametric Involute Profile Bevel (Conical) Gears take the following parameters:number_of_teethcone_distance: The distance from the pitch apex to the outside pitch diameter.face_width: The length of the teeth.outside_circular_pitch: The circular pitch at the outside pitch diameter.pressure_angle: Defines the shape of the teeth.clearance: Gap between the tip of the teeth on one gear and the root of the teeth on another meshing gear.bore_diameter: The size of the hole in the middle.gear_thickness: The thickness of the gear for bevel_gear_back_cone finish (see below). backlash: Makes the tooth width smaller to make a gap between teeth of correctly spaced gears to allow for manufacturing tolerances.involute_facets: As for spur gears.finish: Specify either bevel_gear_flat(0) or bevel_gear_back_cone(1). If you don't specify this parameter you will get a flat gear for pitch angles less than 45 degrees and a back cone gear for pitch angles greater than 45 degrees. The example shows both with the small gear being the flat one. Update: v5.0 Implements backlash for bevel gears (This was not working in v4.0).

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Spur Gear Fitter Script by cbiffle

I've been working with Greg Frost's gear generator. Getting the gears to mesh requires some math, or trial and error. As a programmer, I don't like doing either one more than once. :-) This script lets you specify the axle spacing and gear ratio and get the circular_pitch parameter. It simplifies fitting gears together.

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http://store.makerbot.com/stepstruder-mk7-complete.html

1. And, thus, the importance of flossing!
2. I included the flossing reference because it was amusing.  But, really flossing isn’t relevant if you’ve got a MK6 or MK7 extruder.

Part Catch Basket for Thing-O-Matic by dustinandrews

Designing 3D objects in OpenSCAD can be very quick and simple. ¹  You can create some really amazing designs by just combining cubes and cylinders in a variety of ways.  However, making a design “parametric” isn’t always intuitive.  As an FYI, a parametric design in OpenSCAD is a design that accepts parameters.

There are a lot of OpenSCAD designs on Thingiverse where the author admits their design isn’t very “parametric.”  With a little effort and a few tips, it is possible to incorporate the power of OpenSCAD parameters into your own designs.  Since I learned some of these lessons when designing an OpenSCAD pirate ship, I’ll refer back to it for examples.

1. Parameters first.  It is so much easier to make your designs parametric from the start.  Going back and making a design parametric can be as easy as find-and-replacing, but typically it is much more work than that.  If there’s any chance you might want to have a parametric version of your designs later – just design that way from the beginning.
   
2. Prioritize.  Decide on the most important parameters first.  Most designs only have a few parameters that are really important.  For example, the two most critical features of the pirate ship were the ship’s scale, as in size, and the thickness of parts.  Once these two were known, most of the other features of the design needed to be modified to fit them.
3. Dependents.  Try to make as many of the features of your designs dependent upon the initial parameters as possible.  The easiest way to do this is to design as much as possible in terms of the original parameters.  I like to do this by setting dependent objects as fractions of the original parameters.  In the example of the pirate ship, I made the largest sail on each of the masts equal to 1/2 the size of the masts themselves.  The other sails were even smaller fractions.  By making these features defined in relation to one another by fractions, they will always end up in the same appropriate locations with respect to one another.  Thus, the three sails on each mast should always line up together.  Throughout the design, I tended to design things in terms of 1/2, 1/4, 1/8, 1/16, 1/32, and 1/64.  These fractions are easier for me to manage than decimals.
4. Mix it up.  While you’re designing, change some of the major parameters.  If your model suddenly goes haywire, you know you made a mistake somewhere – either by including a feature that doesn’t rely on your parameters or by a feature that is changed by your parameters in unexpected ways.
5. Modularize.  Start by designing just one aspect of your idea at a time as a module.  Doing so will let you define whole regions of your designs in relation to one another.  For example, one of the modules I wrote for the pirate ship was for a single sail.  I wrote another module that would put together three sales of decreasing sizes and another module that added the large triangular sail and mast itself.  Yet another module collected all three sails.  Once the three sails could be created by a single module, I could move all of the sails around as a single piece.
6. Cheat.  One of the parameters for the cylinder function is “$fn”.  This basically dictates how many facets the circumference of your cylinder will have.  A cylinder with 8 facets will look like an octagon and a cylinder with 128 facets would probably look almost perfectly circular.  I cheated by making triangles by creating cylinders with “$fn=3″ or just three facets.  There are a lot of shape libraries for OpenSCAD, but this was a quick and simple way to get an equilateral triangle.  Each of the sails is actually a cylinder, turned on its side, with just three facets along the circumference.

What other suggestions do you have for someone who wants to make their designs parametric?

1. Thanks to dustinandrews for tagging their Part Catch Basket for Thing-O-Matic as with “openscadtutorial” on Thingiverse!

Printing plates for Mr. Maker by ErikJDurwoodII

Yesterday I spent some time organizing the parts in the MakerBot mascot entry “Mr. Maker” by ErikJDurwoodII into printing plates.  Afterward, Erik asked how I did this.  While I had posted some tips on creating printing plates earlier, I didn’t really give a decent step-by-step guide.  I like using OpenSCAD to orient the parts, but I’m sure there are other ways.  Here’s my process:

1. Orient.  Make sure all STL parts are centered and flat on the build surface.
1. The easiest way to ensure this is to open the STL in ReplicatorG, click “Move” in the bottom right corner, then “Center” in the right panel.  Matt demonstrates how to do this in MakerBot TV episode one @ 2:56.
2. Sort.  Sort all STL’s by the number of times each part needs to be printed.  I like to put them into folders labeled “1″, “2″, “3″, etc.
3. Make a Plate.  I use a simple OpenSCAD command to create a transparent representation of the build area.  I like to use an 80×80 mm square so that I can be sure everything is going to fit.  Here’s the command I used:
1. % cube([80,80,0.01],true);
4. Practice Moving/Spinning.  Using just the OpenSCAD translate and rotate commands, you’ll be able to move, spin, and place any part.
5. Plan for Multiples.  Looking at all of the parts that need to printed multiple times, see if you can place them together so that printing a single plate more than once will give you the proper number of parts.
6. Biggest Parts.  The largest parts that can’t be included with other large parts will essentially determine the number of printing plates you need.  Place each large part onto it’s own plate.
7. Medium Parts.  Once you have a general idea of the number of plates you need, as determined by the biggest pieces that can’t be combined with other parts, try to fit the medium pieces in and around other parts.  If you can’t fit them around the large pieces, you’ll need to create a plate of medium parts.
8. Small Parts.  The smallest parts can be sprinkled in and around all the large and medium parts.
9. Pro Tips:
1. If you have a part that needs to be printed an odd number of times, consider putting a single occurrence of this same part into a plate that needs to be printed only once.
2. Sometimes it helps to have extra parts, so printing an even number of a piece that you need an odd number of isn’t actually very wasteful.
3. Consider mirror-flipping a part if it won’t fit.  Some parts won’t fit onto a plate unless they’re flipped, but are just as functional either way.
4. Consider printing small parts multiple times if you can fit an extra instance onto a plate.  Small parts can rip off the build platform, get deformed, break, or get lost.  Printing an extra small part along with larger parts doesn’t add that much time or plastic and will probably save you a lot more time down the road.
5. Save yourself some heartache and make sure you use a Stepper based extruder that will allow you print without a mess of strings between all the parts.
6. Always include the individual STL’s for parts even if you’re uploading printing plates.  Sometimes people just need to print or reprint one little piece and it can be a real pain to carve one out of a printing plate.
10. Rock Star Tips:
1. Some parts such as complex gears or external pieces can better benefit from high resolution, slower printing, or different infill ratios than other simple or internal pieces.  Consider organizing the parts so that certain pieces that need similar resolution/speed/infill ratios are printed together.  Thanks to Bobbens for including this tip in his Mini servo gripper plate.
2. How about creating the entire GCode setup for printing everything using an Automated Build Platform?
3. If you’ve got a MK7 Dual Extruder setup with soluble support material, you could stack parts on top of one another.  This means you could turn a multipart print into one single long print task, print everything as one big chunk of plastic, drop the result in water, let the PVA dissolve, and pull out all of your parts.

Do you use production or printing plates?  What program do you use to make them?  What additional tips do you have?

We’ve liked 3dTin for awhile now; it was a clever, useful app since it debuted.  But, unlike many clever, useful projects, this one has actually had its development continue, and it’s seen some major improvements.  In fact, there are a couple of big ones you should know about: first, they added cylinders!  And now, they’ve added the entire library of primitive templates that you see above.

3dTin is probably the most accessible way to get into 3d modeling, so it’s really great to see it becoming a more powerful and full-featured tool.  Most of the designs are still a bit, well, low-rez, but it’s clear that it’s much more than a one-hit-wonder.  If you like what you’re seeing with 3dTin (and Cadmium, a 3d modeling library for Python) you can support them by purchasing the premium app on the Chrome store, or just logging on and making cool models!

South America map puzzle by chapulina

This tutorial on how to create a 3D printable map puzzle by Chapulina is far too awesome to be relegated to a simple footnote.  Chapulina uses a combination of open source resources and programs to achieve this final result, including maps from Wikipedia, the vector drawing and image manipulation tools from Inkscape, and the DXF support of OpenSCAD to create these cool 3D printable puzzles.

Chapulina’s title of their blog post and tutorial was far more generic than simply “creating 3D printable map-puzzles,” as well it should have been.  This same exact methodology could be used to create a 3D printable¹ puzzle out of any image.

What will you do with this new found knowledge?

online maps, inkscape,openscad dxf

1. Or lasercuttable!