Thursday, May 31, 2012

Project HGUC Sinanju Start to Finish: Assembly & Seamlines

Starting at the beginning

Thanks for the Gyan drawing Joseph, I really like it!

I like the box art for this kit, it's more exciting than the minimalist MG Ver. Ka. Sinanju Box

Getting Started:

Hopefully by now you have this or another kit like it in front of you so you can follow along.

First thing you should always do is check to see if you have all the plates, you wouldn't want to get halfway through a kit and realize you're missing something.
At this point some modelers will take the whole plates and give them a good cleaning in some warm soapy water. Washing the plates is important, it removes any remaining mold releasing agent (think non stick cooking spray, but for models). The mold release can sometimes prevent paint adhesion. I prefer to wait until after the kit is assembled and all the sanding is done.

Let's get ready to assemble.

Removing parts from sprus and sanding:

When you need to buy or replace your modeler's tools do not buy them from your local or chain hobby shop. These stores usually charge a huge markup.
If you don't already have a set of basic modelers tools, you can find a range of tools that I normally use here:

Modelers tools by GGD

Side Cutters: I call them nippers, you use them to free parts from the runners

X-acto Knife: A modeler's bread and butter, you use them to clean up nubs & cut decals

Sand paper: Various grades used to smooth and polish nubs
Okay everything is laid out here on my cutting mat.

When you go to cut out a piece make sure you leave some of the tree material on each part like this.

Depending on the layout of the mold you won't always be able to leave this much, but try to avoid cutting right against the part.

Once you have freed the part from the tree it will look something like this.

Use you nippers to cut closer to the part, you should be left with a nub.

Use your X-acto knife to gradually shave down the nub, until you are almost flush with the plastic. When using your X-acto knife remember two rules, never cut towards yourself, or 'in' to the plastic. If you slip in either case you'll do damage to yourself, or to the part. Believe me on this part, I don't have any 'complete' finger prints left...

Take a piece of sanding paper, (I'm using a set of sanding pads from Alpha Abrasives they're a bit pricey, and not available everywhere, but they give you more control and overall they do an acceptable job). Using a coarse grit take a few light swipes until the nub is flush. If your sanding material is leaving deep scratches you should consider using a finer grade.

When sanding a flat plane like this piece, make sure you're sanding as flat as possible, otherwise you will round off the corners.

The nub is sanded off, but the finish is rough.

Once the nub has been sanded down, use a finer grit to polish away any scratches. Don't be too obsessive about getting a completely smooth surface, but you need to remove any deep scratches, primer will help to level out lighter scratches.

After using a finer sanding stick the part is smooth and scratch free.

 If you have two round parts like these two hip pieces, the best way to sand them is to put them together and sand them as one larger piece. If you were to sand them individually you might end up with miss matched edges.

Dealing with Defects

Flashing can happen during the molding process. It's pretty common to have a few pieces with flashing per kit. But It's also very easy to correct.

Follow the same sanding steps for removing nubs, and you should wind up with...

If you're building the Sinanju you should check the following pats for flashing: shoulder joints where the chest connects to the arms (pictured above), the upper wing binders, both sets of waist piping and the inner red portion of both wing binders.

Removing seam lines

Bandai is really good at hiding ugly seam lines 90% of the time, occassionaly a kit will have a couple of spots where they can't hide them.
Overall the Sinanju does a great job of hiding them, but we can still see the seams on the propellant tanks, rifle, knees & knee joints.

To fix this problem we're going to use Tamiya's extra thin cement to make the parts fit together seamlessly.
Grab two parts that are going to fit together, like these two knee joints. Fit the parts together so there is only a fine gap left in-between the two parts.

Then take your cement and touch the tip of your built in applicator to the gap. The cement should be drawn in by capillary action. You may need to apply cement in several areas to get total coverage. Once the cement is applied all around the part, squeeze the two pieces together. If you did it right some of the cement will squish out from the gap. Leave this part to dry for a few hours

Once the glue has dried completely, we can sand it off. You should be left with a seamless looking piece like this.

You don't need to, glue the entire piece together, in fact it's much easier if you only glue the seams that will be showing on the finished kit. For the knee joints, I only glued the forward facing seam, because the back is hidden behind some piping detail.  

Finished Assembly:

The first part of this multi-stage project is over and done. If you're following along with me you should now have this proudly standing on your work surface.

I have to admit that the HG Sinanju looks every bit as mean and menacing as it's much larger brother. It's tough to get a bad standing pose out of this guy.

The Sinanju is a bit back heavy, but that's to be expected with the large wing binders. We'll see if we can't stiffen up some of the joints to solve that problem.

Next Episode

We're going to start modifying the Sinanju to make it meaner and sleeker. There are already a few modifications I can think of to improve the kit. We'll cover changing part geometry, joint stiffness, and puttying.
Stay tuned, and if you have any questions about any of the work included in the segment please post a comment below!


  1. Great write up so far and I can't wait to see more! Thanks for sharing.

  2. Hey Dan, great job so far. I have two questions about sanding though:

    1) I've heard about people building nice looking kits without using paint like this one ( I was wondering if you had any experience with this sort of technique and what your thoughts on it were.

    2) From time to time I end up with some small part like the yellow pieces of the chest vents on the RGM79 or the RX-78-2. Whenever I try to sand these, I end up sanding my fingers more than I do the part! Do you have any tips for avoiding this?

  3. Hey,

    Those are great questions.

    1) I haven't seen that technique yet, I'm kind of surprised that he's sanding down each individual piece to eliminate the shine and then top coating which also eliminates the shine. It seems like he could save himself a lot of time by skipping the first step. Also you might notice the repeated sanding is rounding off the corners. If you're going to use this technique its really important to preserve the angles by sanding flatly.

    2) I have this problem too because I have large fingers. I think a tool like this: would be really helpful. It's a pair of pliers with a nylon coated head. They shouldn't damage the plastic while holding the part, and they should give you a greater degree of control when holding the part.

    Hope this helps!