This project was to try a simple project to evaluate vacuum forming with PETG.
The part I chose is the canopy for an Esky Honey Bee King II helicopter.
First, side elevation and end elevation drawings were done.
The cutting lines are marked on the mould. This mould will be used for two sizes of canopy. The larger cut out line is for the Honey Bee and the smaller cut out line is for a smaller helicopter.
After the outlines of the mould were cut, the edges were rounded with files and sandpaper to acquire the desired shape. Care was taken to ensure the edges to be joined together were in line and not at an angle.to each other.
A layer of wood filler was put over the surface of the moulds and smoothed off with sand paper.
I found that I obtained better results with HIPS for these reasons.
1. HIPS does not require preheating to removed absorbed moisture before it is formed.
2. HIPS is better at forming tighter curves than HIPS. At the tip of the nose, PETG tended to form ‘fillets’ that had to be filed flat. HIPS forms very tight curves without ‘filleting’.
3. Gluing HIPS is easier when Revell glue for plastics is used.
A few more designs were considered.
I like this red one. The alarmed expression seemed appropriate to the way I was flying then.