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 25 / 10:33pm

3D Printing porcelain.... and potato.... and chocolate!

Earlier today I dropped into Bits from Bytes HQ in Clevedon and met up with someone I’ve been “talking” with on the BfB forum for well over a year. And what a fantastic meeting it turned out to be. Dries Verbruggen (known to many as “Unfold”) has come over from Belgium to spend a couple of days with the guys from BfB working on a design for a new RapMan extruder. Only this time it is for ceramics, potato and chocolate… or any other “paste” material. And it looks to me like they have hit upon a really interesting design…. The chocolate looked yummy too!

Dries is a really talented guy… not certain whether to call him an artist, designer or ??? and you can check out some of his work on his website http://www.unfold.be/pages/projects .

(download)

I can’t wait to get my hands on the new extruder when it goes into production… already I’m thinking of projects that we could do in schools.

 

You can see the RapMan printing clay and potato on YouTube

 

 

Filed under  //  printing  
Feb 15 / 9:32pm

Convert an iPhone into a Satnav (for a bike)

One of my GCSE students (age 16) has decided that for his GCSE D&T Product Design exam he would make a device that would hold an iPhone on the handlebars of a mountain bike… and using a suitable app he could convert it into a satnav.

The images here are of the “just printed” parts for the mount and frame that attaches to the handlebars… the clips for fixing the iPhone and Velcro straps are to be added later.

The really impressive part in all this is that these are the first prints by this student and the completed project (including a design folio and photographic production log) will be about 20 hours of work.

When it is completed and mounted on his bike I will try to get him to take some more photos, so keep an eye open for part 2 a little later on.

(download)

Filed under  //  Education   printing  
Feb 10 / 7:17pm

William Morris would have used a RapMan...

Sam_0298

Crossing Boundaries - Art (and Textiles)

One of my D&T A level students also does Art. … and being Aaron Thorogood, one of the students who came to Euromold with us, he wanted to see if he could use 3D printing in his coursework project. So, I have to give him some credit for coming up with the idea of block printing.

I sent him away to design a block using Pro/Engineer (Creo Elements/Pro) reminding him to make sure that he “flipped” the image. A few minutes later Aaron had produced the first design and converted it to g-code with Axon. Of course this was far too easy… we found that the letters didn’t print well (too skinny) so this is where the ability to design iteratively with RapMan and BfB3000 is so valuable… Aaron produced design version 2.

Armed with some block printing ink and one of those rubber rollers that artists use for this sort of thing we inked the surface, placed the block  between some MDF scraps and a bit of leather… and squished it in a metalwork vice.

It works!!!!

Ok, we need to do some more development work on this and maybe do some research but it looks like Aaron has come up with a winning idea.

 

I then started thinking about next steps and what this block printing know-how can be used for…. And my mind has started to wonder about printing textiles. After all William Morris (English Arts and Crafts movement 1880 -1910) used wood block printing for his beautiful designs.

 

Maybe a topic for a new Teaching and Learning resource in the BfB wiki soon??

 

Filed under  //  Education   Resources   Teaching and Learning   printing  
Jan 14 / 6:22pm

Safe support material removal.... that really works!!!

As some of you will possibly remember I upgraded my RapMan to a double extruder some time ago and did some prints with ABS for the object and PLA for support material. I did my first prints like this during last summer and I used Caustic Soda or Lye (NaOH) to remove the support really quite successfully. A couple of months later I tried again and with a dangerously strong mix of NaOH even after 2 days the support was still intact…. I suspected that it was because of the colder weather. I was also very concerned that this was far too risky to do in school, we needed to find an alternative approach!

So I talked with the guys at BfB and thinking around the problem it started to become obvious why the PLA is biodegradable…. It’s to do with 2 things- HEAT and MOISTURE. i.e. the things that make it degrade when buried in a rubbish tip or compost heap.

The guys at BfB then started experimenting and passed on their ideas for me to try out too. And here is the good news…

 PLA SUPPORT MATERIAL CAN BE REMOVED JUST WITH HOT WATER !!!

The process is somewhat slower than with NaOH but considerably safer.

As a result of this testing it looks like all you need to do is immerse the part and support into a container of hot water at 80 degrees Celsius for about 36 to 48 hours… after this time the PLA starts to go brittle and crumbly – you can easily and safely crush it (almost to a powder) in your fingers.

The problem is how to maintain a container of water at 80 degrees Celsius for this amount of time… The guys at BfB allowed me to borrow an ultrasonic cleaner tank for a few days and this seemed to work very well… I only used the heater not the ultrasonic part which may or may not help (not tested yet)… I have a feeling BfB might consider supplying these tanks sometime.

So for support materials removal…

Method 1… SAFER…. But slower… Hot water at 80 degrees Celsius for 36 – 48 hours

Method 2… RISKY… But faster… Hot, NaOH (time depends on strength and temperature)

(method 2 is made a bit safer by using a proper tank but don’t forget NaOH is very corrosive and you should carefully assess the risks to yourself and others before you consider trying it)

For those of you who have not come across ultrasonic tanks there is a photo attached (other styles and makes are available) In school why not see if your science department has one of these that you can use.

Tank
Essential to have…

Thermostatic control, A lid to prevent evaporation, Safety cut-out (as liquids and electricity don’t tend to work well together), Correct voltage machine, A timer is probably useful, Ultrasonic may or may not help… not tested by me.

Filed under  //  Health and Safety   printing  
Jan 9 / 3:22pm

Students to hold a volcano in their hands

In a few weeks’ time I’m about to run a pilot “workshop session” with a group of teachers and students from the D&T and Geography departments of my own and a neighbouring school.  All very exciting and a different approach to the “Mt St Helens” volcano project that I posted on the BfB Wiki http://wiki.bitsfrombytes.com/index.php/Geography_-_Mount_Saint_Helens_Volcano . More about this later J

 

Anyway, I started to get together all the resources I need for the project and realised that even after  several months since I published the project I had never printed out a BIG “before” and after “model”. So, that was this weekend’s project!

 

For the technically minded, the details of how to convert satellite data to a .stl file is in the resource listed above. The print was made using white opaque PLA. The g-code was produced in BfB Axon using a modified version of Andrew’s new profiles (z=0.5mm, fill =0%, solid layers=3, shells = 4, Temp 195, all other settings as standard in “BfB2 z0.50 PLA Fast”)…. Build time about 2.5 - 3 hours each.

 

Anyway, I’m sure you will agree that they look pretty good… even if they do look a bit like icebergs.

(download)

Filed under  //  Software   Teaching and Learning   printing  
Nov 12 / 9:12pm

A nice 3D print by a student

Bracket

I just thought you guys would like to see this print... and this time I can take very little credit for it 

One of my D&T Product Design students is designing and making a flat pack moveable kitchen unit/trolley (a bit like an Ikea style butchers block on wheels)... as it is intended to be flat-packed he is designing the fixtures and fittings for it too... to get started he decided that for the first fitting he would produce would be the bottom corner bracket that holds the sides together and attaches the casters (wheels)- and being a little uncertain about the strength and size required he based his experimental part on an existing design that he "borrowed" from a conventional kitchen unit at home. (I do wonder if his parents know)

As you can see the ABS print (the red one in case you were wondering  ) came out really well and as a test piece was very successful.... now he has started on his own designs that are more specific to his unit/trolley.

It is worth noting that this is a photo of the part straight off the machine with no post processing, cleaning up or even photo re-touching!!!

Dave

Filed under  //  Education   printing  
Sep 9 / 9:35pm

BfB, PTC and Scalextric

Two Blog posts in one day! Must be more good news!!!

 

Over the summer holidays I was contacted by PTC (the company who produce Pro/ENGINEER) about testing out some ideas for an international project that they support in schools and colleges. I couldn’t resist the challenge and the opportunities that it might offer for students.

The project is called Scalextric4schools (see http://www.scalextric4schools.org/  ). Basically students can design (using Pro/ENGINEER) and make scalextric slot cars to enter into an international competition.  Tim Brootherhood from PTC was at the DATA Digital D&T conference and wondered if BfB printers could make a scalextric car body shell.. so he sent me the files to see if it was possible (btw the Makerbot guys had already given it a go but the size of their machines means that they can only produce the body shell split into parts). As you can see from the pictures in this post with a little help from the guys at BfB we printed a body shell with support materials (those of you who visit the BfB forum may have seen some of these before when I started a discussion about twin extruders and support materials).

(download)

So, If you are looking for a new project for your school or college you might like to consider taking part in this competition, full details are on the website mentioned above.

When I get all the parts to complete these cars I’ll post some more pictures. If you have a go please think about posting some photos on the BfB forum.

Dave

PS. If you are wondering about the strange looking red car in the photos it’s a printed mould for vacuum forming car body shells... another experiment that we are trying out.

 

Filed under  //  Education   Resources   Teaching and Learning   printing  
Aug 17 / 1:02pm

Printing with support

This resource is for the slightly more advanced. It introduces the idea of printing using support material for more difficult or complex objects

Support_
The full PDF file can be downloaded from...
http://www.bitsfrombytes.com/wiki/index.php?title=Printing_with_Support

Filed under  //  Resources   Teaching and Learning   printing  
Aug 11 / 8:46pm

Thin Walls... testing the limits

Over the last few weeks I’ve been playing with all sorts of settings and software to try to really get to grips with what they really mean. I got frustrated by doing large prints so I designed a couple of objects along the way that allowed me to see results quickly. The square and diamond are simple 25x25 parts that allowed me to check on solid surfaces (shells and surface layers at 0, 45, and 90 degrees.

But what was really starting to frustrate me was printing objects with thin walls (containers). Walls that were really thin were not printed, quite thin walls ok, and thick walls were no problem… it was the ones in between that were proving difficult.

So I designed a “Walltester” with walls from 0.1 to 2.0mm in 0.1 increments and also 2.5 and 3.0mm for good measure. This allowed me to see…

The smallest wall size that is processed

Walls that print as a single line

Walls that print as 2 lines side by side

Walls that print as 2 lines with a gap

Walls that print as multiple lines

Walls that print as multiple lines with zig zag infill

 

Walltester_
Tester

The full details of my testing can be seen on the Bits from Bytes forum http://www.bitsfrombytes.com/forum/post/thin-walls-testing-limits You can also download the “walltester” which is on the BfB wiki http://wiki.bitsfrombytes.com/index.php/Test_Parts

I don’t think my testing was totally scientific or the results were conclusive but I certainly enjoyed finding out what was possible and gained a better insight into the capabilities of the various software packages… and also what I can and can’t do with my shiny new RapMan.

 

 

Filed under  //  Hardware   Software   printing  
Aug 6 / 1:35pm

Blast off!!

How about designing and printing your own rocket.... a real one that flies! Ok so this project is about using sodium bicarbonate (baking soda) and vinegar to produce CO2 to power a model.

Rocket

http://www.bitsfrombytes.com/wiki/index.php?title=Blast_Off

Thanks to "tastybento" for the use of his idea and designs on Thingiverse for this project

Dave

Filed under  //  Education   Resources   Teaching and Learning   printing