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Monthly Archives: February 2012


3D printing @ Clevedon School …a video

I have taken quite a few photos of 3D printing projects done by my students and found them all lurking on my iPad. Rather than just delete them off I decided to put them together into a short video clip… You might recognise the projects from some of my recent blog posts!

Ok, not earth shattering stuff, but I enjoyed doing it.



FYI … I used the Animoto app on my iPad to make the video. Animoto can also be used free on PC and Mac by visiting their website. Educators can sign up for a free account that enables longer videos and give you a code for student use too!


More student products improvement with 3D printing

In an earlier post I showed how a student designed an improved pencil sharpener (the green one in the photo gallery). He wasn’t entirely satisfied. After doing some further consumer research he realised that although his new design was really quite good the market was more limited for a desktop device… So after re writing his specification to match his research he came up with this device… It’s a first generation design and will obviously improve in subsequent iterations but I must admit I really like the elegance of this solution.. Fold out handles for a better grip, uses a standard pencil sharpener for its mechanism and just the sort of quirky design that appeals to youngsters.

I’ll hopefully let you know more as this progresses… Unless his design becomes a marketable product !


Students improve products with 3D printing

If you browse back through this blog to an entry I made on 2nd February “improving products with 3D printing” I showcased some of the work done by my students in designing and 3D printing prototypes of improved products…. Here is just a taster of how a simple design has evolved with the help of the relatively rapid modelling that can be done with 3D printing…. Our 3D Systems Bits from Bytes machines are really being put through their paces!

In the photo galley in this post you can see how this model has changed… The original red model was intended to be used with the opener pointing towards the finger tips… Through testing the student has decided to reverse this. The finger rings have now been angled to be a little more ergonomic and the design is now approaching something that would be viable. … Forgot to say that this design is intended for domestic and commercial use… It is now the sort of design that a barman could “wear” throughout a shift behind the bar and have a bottle opener “to hand” and ready for instant use whenever there is a need to open a bottle…. Just writing about this is making me drool… I could crack open a cool bottle right now!


Creo Parametric for 3D printing in schools


Really not certain what the proper name is for this program… “Creo”, “Creo 1”, “Creo Parametric”, “Creo Parametric 1” or ?? I’ve seen it referred to as all of these (even by PTC themselves)

Anyway whatever it’s called I found out yesterday that DATA the organisation that has been administering this software for schools in the UK are handing back the responsibility to PTC in a couple of months time. I also found out that with PTC’s education program I can upgrade my school install from creo elements pro (wf5) to Creo Parametric. So I sent off my emails, registered, and downloaded the software. I must admit it was a bit of a fuss getting all the licence files, Host ID and other details up together but after that the install went really smoothly. I had a bit of a tussle getting the program to display things properly but that’s down to my ancient laptop not dealing with opengl graphics very well, so had to change it to win32_gdi and now it works fine…. Probably not as pretty on screen but hey ho….

So, I’ll give it a go for a few weeks on my machine before risking a full network install in school, it will give me a chance to get to grips with all the new fancy stuff and also let me find where they have hidden everything on the lovely new ribbon toolbars…. A good idea perhaps to do this before I try teaching it!

Good news is that it opens files fine from previous (education) versions of creo elements, pro engineer or whatever it was called…. And the stl files export ok for 3D printing… So let’s see how it goes. I’m sure I’ll be blogging about all this again soon.

Support material removal revisited

Before reading this post It might be worth reading a blog entry that I made back in January 2011 http://rapman-education.posterous.com/safe-support-material-removal-that-really-wor

In that post I revealed that PLA support material can be removed from an ABS printed object using hot water (or for a quicker but riskier result you can use caustic soda NaOH). The hot water method requires the object is kept in hot water for 36 to 48 hours…. But this is a little difficult to do. Help is at hand though as 3D Systems Bits from Bytes now supplies ultrasonic tanks that will contain the liquid and keep it hot.

These might seem a little pricy but certainly In schools where safety is so important it’s a worthwhile investment if you regularly print with PLA support material.

3D Systems Bits from Bytes have just released a video on YouTube that shows you how it’s done.


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


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


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.


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


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


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)

Blogging and Tweeting


As many of you who regularly read by blog (I’m still amazed how many hits I get for my blog posts) will know I am the Head of D&T at Clevedon School in the UK…. And some of you will have seen that I tweet too!! But you might not know where to find me in the “twittersphere” or “blogosphere” (are those really words?) … here goes with an update of my contacts

This blog: http://rapman-education.posterous.com/ (specifically about 3D printing in education, but with a few bits of news about other interesting developments thrown in)

My twitter name: @davewhite60 (usually about 3D printing in education, but other stuff sneaks in occasionally)

My school D&T department blog: http://www.clevedonschool.org.uk/blogs/products/ (not just 3D printing but also news of students, projects and developments in my school department)

My school D&T department twitter name: @clevedondt (just for tweeting about my department)

So, why not visit the blogs and maybe follow on twitter…. It will be interesting to see what develops.

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