Placing engines in 1/12th motorcycles

Featuring the Aoshima Zephyr

by Mario Covalski  © Modeler Site

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My first motorcycle models, during the 70’s, were Tamiya’s 1/6 scale models. The parts were big but the building sequence was almost identical to the 1:1 scale models. Beginning with the 80’s I discovered the new scale for motorcycles (1/12), and found out that almost all of them used the same method to build the frame: first paint both halves and then glue them with the FINISHED engine in between. Something similar to airplane models, first you have to finish the cockpit and then you have to glue it between the fuselage sides and then paint everything; the difference here is that in our case (motorcycles) we paint the frame halves before gluing them.

Have you ever tried to glue two gloss painted parts, not fitting well, with a “seam line” that shouldn’t be noticed?

The final result is not very clean and makes a nightmare out of an otherwise simple operation. All motorcycle frames have crosspieces which, generally speaking, are too small due to the scale and the fit is less tan good. Moreover, the center frame which holds the front fork is in plain sight and difficult to hide in a tourism cycle so, the joint line is quite visible.

If you are building one of the new models, with cowling parts, you probably don’t have this kind of problem because the frame keeps out of sight once all the parts are in place. But, if like in this case, we are talking about a small “nuke” cycle, the frame is what it calls our attention, specially if its not painted in black.

My main focus with this note is to share with you a simple technique that I have been using for a long time, and show its application with this beautiful model by Aoshima. At the same time, I will take advantage of the pictures to show how nice the model looks once it is finished.


Not this way!!!...

This is what I usually think when I read a building instructions sheet which explains in an easy way what it is almost impossible in the “real world”, or at least you know beforehand that the final result will be a disaster. So, it is easier to waste some time modifying a kit, as well as the building sequence, in order to have a more pleasant finale when all the parts are painted.

Step 1: The problem

This picture show both frames separate and glued around the engine, which is also assembled. Everything seems so easy to do because the parts are not painted yet, but the fit is not perfect and there are some parts which will need putty and sanding in order to “vanish” the joint line, or it will be difficult to get a strong bond. Blue circles show the “conflict” zones; note that is very difficult to get to the joining points with the engine in place and both frames halves painted.

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