Thursday, January 29, 2009

MSN-06S Sinanju - Work Log 10 - Backpack complete but not without... BREAKAGE



Yeah... I'd love to say that was my work. I mean... dayum! Pretty impressive don't you think? Customized main thrusters and decals for this Sinanju. Really cool. I still like the original ones though. If anyone knows who the original modeller of this is, please enlighten me.

Now onto my Sinanju. It was fine after the initial assembly. The problem came after I painted it.

Now... the wings of the Sinanju look beautiful but how are they connected to the back pack? By a thin elbow joint. Really, if this were real life there's no way that such a flimsy part could hold the entire weight of that wing/thruster never mind holding up to the stresses put on it when that thruster is ignited. 64300kg of thrust per wing. Really it's actually quite ludicrous. Totally defies the laws of physics... for metal! Not for plastic though.

Anyways... what happens when that thin little elbow joint breaks? The answer is; No more wings! And that's what's happened to me. To both of them. Same break. Where? Take a look.


Right on the top. The rounded surface... it's about 2mm thick. One word for this design. RIDICULOUS. Sinanju goes down a few more points for this idiotic design, couple that with the shield debacle and well... this legendary kits starts to look a bit less attractive.

That's not to say that this part is going to break for everyone. I think it broke for me because I painted it without priming. I have a couple of theories about this.

Largely, I think that the alcohol in the paint made the plastic a bit softer/more brittle on that outside surface. No primer for protection. I had this problem with MG Impulse's knee-to-thigh lever and HG GM Powered's knee joint. They both snapped. For the same reason I think. Both were very thin parts under a lot of stress. The direct application of paint to the surface probably didn't help matters at all.

After I inserted it into the backpack is when the cracks started appearing. It didn't break outright. Neither of them did. They both broke the same way. First by becoming loose from tiny cracks and those tiny cracks became larger ones due to the stresses being put on them. Eventually I just broke the piece along those natural crack lines, glued the part back together, put some extra glue on top to strengthen it and then more paint on top to make that 2mm width about 4mm. Part of me is thinking to wrap a thin piece of 1mm pla plate around the part and glue it in place (I have the clear type of pla-plate that folds and rolls.).

Right now the elbow joints are functional but I have to be really gentle with them for obvious reasons. I really would like to do a bit more work on their structural integrity. I think I might still, just for piece of mind.

Outside of that it was pretty standard. Re-painted a lot of the pieces. Had to sand down some areas to ensure that the movement was maintained. Lots of decals on here.

I gave the fuel rods some special attention. Glued shut, puttied, sanded, primed and sprayed. I did a really good job on them. They are totally smooth (no seams) and I did my best paint job to date on them.
The key was distance. I held them really far away from the nozzle of the spray can and let a 'cloud' of paint hit the surface instead of a 'stream'. Worked like a charm. I'm going to paint all my pieces like this from now on. I might waste a bit more paint but it gives me a perfect surface with no drips and that saves more time for me in the end. Less touch ups.

After working on the backpack I used my Gundam markers A LOT for paint touch ups. Really easy to use and nothing to clean up. I went out today and bought from more for the other colours that I doing.

Now, onto the legs!

5 comments:

  1. well that sucks breaking the wing connector and all.. and also same here about the Shield i mean WTF!! no handle!?!? hehehe well looking forward to your finished sinanju!

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  2. You can fix the broken piece using plastic piece or epoxy, that would even strengthen it.

    How come your work log don't have any pics of your progress?

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  3. what kind of paint are you using? With the shift from polycaps to ABS, this kind of weakening will be a larger problem. I had a HGUC Z-Gok E ruined because the glue I was using (Humbrol) completely weakened the ABS plastic to the point it became brittle and broke.

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  4. gr3. - yeah that no handle thing really pissed me off! how could they not include something so simple!?

    anon. - i used just liquid cement and it was fine but in the end i took your suggestion and used epoxy putty to make that part more sturdy. and my work log has no pics because i dont want to reveal my colour scheme just yet. it'll be very apparent if i show pics of any kind.

    darth - im primarily using tamiya mini laquer spray cans. thats the paint i used on this damaged part at least. sucks about your z-gok. i guess in order to fix that part you had to switch glue types eh?

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  5. nah, I gave up on it. It is buried on my shelf of forgotten Gunpla. I am a bit concerned because the new Macross Frontier kits are all ABS. I've actually reverted back to Testor's gel cement applied with toothpicks. It gives a nice, strong bond and plays nicely with the ABS. I hope my Tamiya paints don't kill the ABS.

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