rapman-education's posterous

rapman-education's posterous

Dave White  //  A place for educators, teachers, lecturers and students to find "stuff" about RapMan,BfB3000 and BfB 3DTouch printers... The unofficial Blog by Dave White, Advanced Skills Teacher and Head of D&T in Clevedon School UK.

Feb 20 / 12:25am

CAD to STL for 3D printing

The usual steps in producing a 3D printed object is to produce the design in a 3D CAD program and export it as a .stl file ... This is because many of the post processing programs that generate the instructions to drive the printer (g-code) can not read the native CAD files. But how do you create a .stl file? It's actually quite easy, here are a few clues to how this can be done in a some of the more frequently used programs. (note that this can vary with different versions of the software... It might be slightly different in the version you use)

Autodesk Inventor

Go to the File menu, then select the ‘Save Copy As’ option

Select STL from the Types drop-down

Click the Options button, and choose the High detail level

Click the Save Button

Catia

Select the STL command

Set Maximum Seg to 0.015mm

Select the model and > select Yes

Select Export > type File name > OK

Creo Elements (pro engineer)

File > Save copy as

Select STL as the file type and enter a new name for the file

In the pop up box Set chord height to 0. (The field will be replaced by minimum acceptable value with smaller triangles for a smoother object).

Set Angle Control to 1

OK

Google Sketchup

Install the stl export plugin http://www.guitar-list.com/download-software/convert-sketchup-skp-files-dxf-or-stl

Open model to export select "Export to DXF or STL" from the Tools menu.

Select "millimeters" as the units for export.

On the "Export to DXF," pop up select "stl."

Enter a filename for your new STL file.

Rhino

File > Save As

Select File Type to STL

Select File Name > Save

Select Binary

Select Detail Controls from Mesh Options

Max Angle = 20, Max aspect ration = 6, Min edge Length = 0.0001

OK

Solid Edge

Open Model & select File > Save As

Select File type as STL

Options > conversion tolerance to 0.015 mm

Surface Plane Angle > 45°

Select Binary type and OK

Name & Save STL file

Solid Works

File > Save As

Set Save As Type to STL

Options > Fine > OK

Save

STL settings: How to change STL settings

File > Save As

STL > Options

For a smoother STL file, change the Resolution to Custom

Change the deviation to 0.01 mm

Change the angle to 5 (Smaller angles will produce a smoother Object but bigger file)

Filed under  //  printing   software  
Feb 16 / 6:46pm

Buggy building with BfB 3DTouch

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 So, I'm the D&T teacher in my school who ends up teaching all the geeky stuff. CAD, CAM, electronics and programming PIC micro controllers. 

The students learn to program simple inputs and outputs using flow chart software and Picaxe chips on some simple circuit boards that I made (I would love to get the students to build their own but time is very limited). They then progress onto a project programming some buggies that I have built. These buggies were built at various times over the last couple of years... And here lies the main problem, they were all different (different wheels, PICs, micro switches and battery containers). It all got very frustrating so it was time to rationalise my set of buggies.

During my half term break I set about 3D printing some new wheels with rubber tyres to help prevent them slipping and a set of battery mounts with Velcro strips to support the battery boxes ( these are colour coded blue and yellow for the different types of chips in the buggies).

I now have a set of buggies that match and after their service / MOT they should be fit for a few more groups of students to use.

Of course the brilliant thing about 3D printing the wheels and battery mounts I have new parts that do the job I wanted. No need to make do with off the shelf parts.

Note: the buggies are available from http://www.rapidonline.com/ as a starter pack for the Toyota technology challenge.

Filed under  //  dt   education   printing  
Feb 4 / 3:28pm

More product improvements with 3D printing by students

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 Following my previous blog post I couldn't miss posting about this product model by one of my students.

As you can see from the photos this student has tackled a project to design an improved pencil sharpener.

This is intended to be a non functional model exploring the ergonomics of the design and some aspects of the functionality such as the hinged waste bin and aesthetics.

A very promising project... I will hopefully post some more as it develops, so keep checking back here!

Filed under  //  casestudy   dt   printing   student  
Feb 2 / 9:03pm

Improving products with 3D printing

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 Our AS Level students at Clevedon School are doing some fantastic coursework projects. Their main project is to design and model an improved version of an existing product... Including some innovative ideas.

As you can see in the photo some of the students have chosen to design improved kitchen products including bottle openers and a pizza cutter. These products need to be ergonomic (designed to fit the human body) and made to a standard where they can be tested.

The products shown in the photo are not their final finished designs but have been made to do some initial testing to check the ergonomics, that the sizes are suitable and most importantly that they will work. To help the students with this they decided to make their prototypes by designing their products using Creo Elements/pro 3D design software and then 3D printing them on our RapMan and BfB3000 printers.

I can't wait to see what their final designs look like!

Filed under  //  casestudy   education   printing   student  
Jan 22 / 1:44pm

Bespoke USB sticks

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 The students in my year 9 CAD/CAM integrated project groups have all come together with different amounts of experience, some having done work with the 3D program Creo/elements pro and others having done none at all. And very few have experience of actually designing for 3D printing. So we did a fairly quick introductory project to help get everyone to the same skills level.

This introductory project was to design and 3D print a custom case for a USB stick. As you can see from the photos there are some very interesting designs. Hopefully some more photos will be posted when the students have printed their design.... And then on to the main project!

 I have posted some Free to download teaching and learning resources for this project on the Bits from Bytes wiki http://wiki.bitsfrombytes.com/index.php/Bespoke_USB_Stick

Filed under  //  education   printing   resources   student   teachingandlearning  
Jan 16 / 10:34pm

Iterative designing for 3D printing

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 One of my GCSE students (15 years old) decided that for his final project he would design a fitting to hold an iPhone on his bike handlebars. I think he must have seen one produced by another student last year and featured in an earlier post on my blog!

So he went away and started to produce some ideas using Google Sketchup I would have much preferred him to have used a proper CAD program for the reasons you will probably see later. Anyway, he finished his design, exported it to .stl format, created the gcode with BfB Axon and printed the first parts. As you can see they were far too big and chunky... This was a real surprise to him as in Sketchup the design looked ok. So, back to the drawing board! ... I wonder if he would have realised his mistakes if he had used Creo Elements/pro or Autodesk Inventor?

His next designs look far more promising, the size is better and somehow it all fits together... So what will the next version look like? ... Well, this is where the power of 3D printing lies. The simplicity, cost effectiveness and relative speed allowed this student to start down the road of an iterative design process. For this him it would have been almost impossible for him to test and visualise what his product would turn out like without printing his first draft design. The jump he made in improving his design would probably not have been possible if he had to have invested heavily in skill acquisition, time and materials for CNC milling. 

Filed under  //  Student   dt   education   printing   teachingandlearning  
Jan 7 / 7:09pm

Kideville. A 3D printing project in UK primary schools

Kideville is a fantastic 3D printing project for primary school children using 3D Systems Bits from Bytes printers.

This YouTube clip is an interview with Dejan Mitrovic talking at the Victoria and Albert museum in London, UK about his Kide project. Dejan talksabout using a 3D Systems, Bits From Bytes BFB3000 3D printer to build houses for his Kideville project. Each building is designed by a student in primary education before being draw in to a 3D CAD package and then 3D printed with the Bits From Bytes machine.
 
 
More details of the project can be found here http://www.kideville.com/
 
Filed under  //  casestudy   dt   education   printing   video  
Jan 3 / 9:26pm

I lost it!

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Ok, I've left myself open to comments like "what do you mean, you lost it ages ago" ... Well what I really lost was a tiny bolt from my 3D Touch printer ( yes, that will teach me for messing around with it). Anyway, the bolt dropped down a gap between my desk and a filing cabinet that my printer stands on and I really didn't want to start moving that lot around.... So...
All I needed was one of those clever "magnet on a stick" thingies, but I haven't got one. But I do have an aerial (antenna) from an old FM radio and a 10mm rare earth magnet, only problem... How do I fix them together (blue tack only resulted in the magnet sticking to the metal filing cabinet).
So I printed a little adapter .... Result, one retrieved bolt and a new "magnet on a stick thingy" for my toolbox.
Neat! 
Attached are some shockingly poor photos of the thingy, a CAD render and the adapter in Axon
Filed under  //  printing  
Jan 1 / 8:35pm

More 3D printing in colour

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Now having easy access to a 3 head BfB 3D Touch printer I really couldn't resist doing some colour printing for myself. But where to start? Well perhaps nowhere better than the lovely globe by "m6mafia" http://www.thingiverse.com/thing:11660 and previously printed by the guys at BfB. The only problem was that Axon requires 3 stl files - one for each colour and a combined file... But I only found the files for each colour! So after a bit of a tussle with Meshlab and Netfabb I was on the point of giving up when I remembered that I could import the 2 stl files into Creo Elements/Pro as an assembly and then export the combined file... Success!!! 
Unfortunately I don't have any blue PLA, so green for the land and transparent for the water would have to do. I suppose the final result doesn't look too bad.
I can't wait to get back to school next week to show the Geography teachers... Hope they're impressed!
Filed under  //  hardware   printing  
Dec 30 / 5:40pm

Mobile 3D Printing

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Just found this from a couple of months ago....Mobile 3D printing...

Ok, not a "hot off the press" story but I love the concept.


This is a project by UNFOLD Design Studio....

"KIOSK,a project that explores a near future scenario in which digital fabricators are so ubiquitous, that we see them appear on street corners, just like fast food today is sold in NY style mobile food stalls. A place where you can quickly get a custom made fix for your broken shoe, materialise an illegal download of Starck’s Juicy Salif orange squeezer that you modified for better performance or quickly print out a present for your sisters birthday.

Unfold gathered information from various designers and labels about how they position themselves towards this scenario. During the Salone del Mobile Unfold three-dimensionally scan new objects presented by these various designers and based on the acquired data, appropriate, sample, remix, improve, up/downscale or copy new objects 3d-printed on the spot".


More information here http://unfold.be/pages/projects/items/kiosk-design-sampler  

attached pictures and text also from UNFOLD.

 

Some of you may remember that UNFOLD was also involved in early experiments in 3D printing ceramics and food items. http://unfold.be/pages/projects/items/3d-printer/lab/date
Filed under  //  article   printing