Thursday, February 21, 2013

A hint of blue causes a heap of trouble: Re-manufacturing the instrument plate to perfection

I know lots of our restoration tales talk about how a particular job was much more work than we ever anticipated but re-manufacturing the plate that the instruments mount to was never going to be one of them....or so we thought.

The original plate was old and tired and needed to act as a model for colour so it would be necessary to make another. Early Dino's had a plate with no brush marks (like the later cars) and were a very particular shade of silver/grey with a hint of blue.

Off to the laser cutter we went and the first task went as easy as we planned. It was then that the real work started. The original plate was made of aluminum with an anodized finish. When anodizing the part needs to be PERFECT or the slightest mark is magnified. Despite being brand new the aluminum plate has a mill finish that needs to be removed. In order to do this perfectly we spent hours with ultra fine sandpaper lubricated in oil sanding the part to perfection. Raw aluminum is incredibly soft so we had to take great care not to make the slightest mark on it or the sanding started all over. Once done the part was given a light frosting and then packed like crazy to protect the surface.

Then it was off to anodizing where the real mountain began. Perhaps it is the constant exposure to harsh chemicals or maybe we just had bad luck but the anodizers we dealt with were just a difficult bunch. No one could clearly explain the process and even fewer cared to spend any time to get it right. You see colour matching in anodizing is very much an art. Alloy, temperature, batch concentration and pH all play a role requiring someone who REALLY knows their craft.

After dealing with several anodizers the Gods finally felt sorry for us and landed us with a most holy man who asked to remain nameless (although I'm sure he has a cousin named Jesus). He clearly understood our project and spent the time required to experiment with various techniques until the colour and finish were a dead match to original. We could not thank him enough and only wished we found him sooner.

Now with the plate finished we can mount the instruments in preparation for fitting to the car.

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