FUEL TANK: TEMPLATE CREATION

This post is so long, it may as well be a 10 part Greek tragedy with some pre-cinema version of end-credit scenes sprinkled on top it. I'm not trying to put you off from reading it, I'm just saying, maybe make yourself a cuppa before you start because you're going to be here for a hella long time.


P A R T   O N E:  T E C H N I C A L   D I F F I C U L T I E S

MEETING DATE: 02/05/2018

Right, so last week, I had hoped that the guys would have the Rhino files opened and exported to an .stl file so I would be able to explore 3D printing a mini version (to help us divide up the sections) and to explore options to CNC the fuel tank (which would act as a dolly to metal form against).

However, it turns out there were issues in regards to the actual file of the fuel tank. It was not my area of expertise so I stepped back a lot in this meeting to let the guys who actually knew what they were doing take charge. I actually feel kind of bad because they were taking so long and in my head all I kept thinking was: how hard is it to open a file and save it as an .stl file

Just look at their exhausted, confused and defeated faces

So yeah, this is going to be a boring post because I'm just jotting down what happened from what I was told and what I had observed.

A breakdown of what happened by yours truly:

• The boys who knew how to use Rhino, couldn't figure out the fuel tank file because there was a grasshopper extension that needed to be used in conjunction. 
• Turns out the fuel tank was a preview version and couldn't be imported into Slicer. 
• Russell single-handedly fixed it for all the groups by putting it in 3DSMAX so that it could be imported into slicer

Russell helping everyone

The template done! 3mm thick plywood ready to get laser cut

So now that's done and dusted it was onto the next section which was the laser cutting and creation of the fuel tank model. Which brings us to part two of template creation:

P A R T   T W O:  L A S E R C U T T I N G

MEETING DATE: 07/05/18

So, I had class that morning, but someone in the group had booked in a spot at the fab lab to get some testers printed out. One of the issues they had discussed in class was that the cut material was 3mm and the gap thickness of the template at the same size of the material thickness (3mm) could be too loose and so the model might end up moving around a bit and not holding together.

As such, they had decided to cut out some testers to see what gap sizes to use. So this is just a few pictures of the experimentation: 

Laser cut rectangles with different gap sizes so that the model would slot together nice and snugly

Look at my dainty little hands modelling this thing... I'm joking, I'm holding it like that because at 3mm gap the tester was falling apart. It was too loose to slot in nicely.

So because of the experimentation we did we the gap sizes, we discovered that having a 3mm gap was quite loose. As such, we decided to make the slot sizes on our fuel tank model 2.6mm as that one seemed to fit the nicest.

A sample of the illustrator file of the template to be used for laser cutting. 

And awaaaayyyyy we gooooo

We very soon found out that there was no need to shrink down and in fact we were very likely making it worse which brings us to part 3 of the template creation.


P A R T   T H R E E:  F I R S T   A S S E M B L Y

MEETING DATE: 09/05/18

There's a video which kind of sums it all up and is probably a great intermission for all the text you've been reading so far.

Well shit.. 

RIP

Alright, so it turns out, whilst we thought that 2.6mm would be a snug fit for the joins, the more pieces you get slotting within one another, the more expansion you will get from the material as well which means that the first two or three pieces will slot in perfectly but the further you go along trying to fit them in, the more difficult it will get and eventually it just won't fit in at all and stuff will break. 

And seeing as we didn't have enough time to get the perfect measurement to fit nicely, it made more sense just to overcompensate the other way by making the gaps 3.5mm and just hot glue gunning it into place. 

P A R T   F O U R:  S E C O N D   A S S E M B L Y

Here's another video to speed things up a little. 

Once it was assembled, we now needed to tape over it so we could do the pattern making and section division. 

And just like that, our model was finally done and dusted, ready to be divided up for metal forming. This was such and easy task and totally did not take absolutely forever.

What did I learn from this though? Biggest take-away would probably be just that, if you can get something done as soon as possible, do it; because with a group of 9, it's hard to organise things and sometimes shit just fucks up because you purely just didn't know (I'm talking about the slot sizes) and when it does mess up, the whole team gets thrown back a week.