Ok this is common knowledge nowadays, but back in the day early builders used rivets and screws of all sorts to attach the ribbed shoulder bridges to the chest! And even worse to the back plate too? And its still a question that comes up today for the inexperienced builder. So as a reminder for all ~ they should be glued to the front of the chest and free to float at the back.
Another thing to note is that the armour should be strapped on the inside, these ribbed parts are for decoration only; and a common costume malfunction from attaching the front and back with rivets or screws is that the armour will quickly crack. So dont do it ~ be screen accurate and follow this advice..
Simply glue the ribbed shoulder bridge to the front of the armour and let it float at the back. As this piece is just there for looks you wont need to use much glue, its a small part and you are gluing plastic together - not holding up a house
And the correct possition of the shoulder bridge is to have 5 smaller ribs visible counting from the end of the chest plate.
To hold the strap neatly in place at the back, a simple piece of thin white elastic is the way to go.
Replica suit
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