Lesson 3: Seam Line Removal

 

Part of the nature of model-building is the presence of seam-lines, where there is a visible gap where two parts fit together. In Master Grade or better models Bandai does their best to hide seams, but with the low parts count of High Grade they're inevitable. The Zaku II I'm building has a particularly noticeable one on the torso (and the leg but I don't have pictures of that) which I'll be using to demonstrate how to Seam Weld, the removal of seam lines using plastic cement and modelling putty.

 

Note: seam welding should only be done if you're painting the model. It looks very bad otherwise.

 

The first step is to take the two pieces and put them together with a small gap in between. Then fill the gap with Plastic Cement. Use more than you'd think. You're trying to make a solid bond and it doesn't really matter if there's some spillover, since you can remove it. Then smoosh the two pieces together. There should be excess if you've done it correctly.

You should then give the cement time to dry and cure. If you don't the next step will start tearing out small chunks of the plastic and fixing it will take a lot of extra time. This is what it looks like when it's done (it usually looks a bit less shiny, this camera is crazy).

The next step is to sand down the excess cement. By doing this you create a single, smooth surface over the seam.

 In theory. In reality there's almost certainly some places where you didn't put in enough cement or something else, and the surface still has pits in it where the seam was.

To fix this you apply modelling putty to the areas that are still not smooth. I for some reason did not take any pictures of this, so I'll be using pictures I found online.

 

Once the putty is dried and cured, sand it down until the area is smooth (pro tip: use a fingernail to check for smoothness). If it isn't, apply more putty and do it again. After priming it will look like this:

 

It looks like there were never two pieces to begin with. It seems like a long process, but it looks very nice and most of the process is waiting.