Passenger door part 2 - glue
Well the original motivation for looking at the door was some stress cracking visible near the hinge, caused by the door skin actually hitting the hinge. Apart from attending to the hinge and door stop, the cracks needed fixing, or at least arresting.
I decided to reinforce the rear of the plastic with a compatible glue, and got some acrylic 2 part glue from a model shop. My original stock for model building had gone off after years of storage, but I knew this kind of material stuck well even to "difficult" plastics and was very strong in itself, so could reinforce weakened areas. It is also thick enough to make a filler if one uses a former to stop it creeping away whilst it firms up.. Here is the one I used - it wasn't cheap, over 5 pounds for this amount:
I cleaned and roughened up the back of the plastic to help it stick even better, and also cut some bits of carbon fibre tow "because I had some" ! A long time ago I made up a matchstick sized stick of carbon fibre with acrylic glue. When fully hardened I could barely flex it with my fingers, and it was immensely strong. So - although it made more work to massage the glue fully into the carbon, I feel better about the belt-and-braces strength added.
Those of you who haven't seen carbon fibre tow, it looks like black baler twine - that hairy string used on traditional hay bales. Here is what the patch looks like applied inside the door, which I laid flat on a soft surface to work on:
You can see the black streaks of the carbon well worked into the resin with a stick. Any fibrous reinforcing like this MUST be well wetted by the resin or it will be weak and no point in putting it in. If in doubt of any technique like this, DO A PRACTICE PIECE FIRST. You will get the hang of it, and see how good / strong the result is, without making a complete pigs ear of the real job.
Now seeing as how the hinge strained the plastic so easily, and as well as tweaking the door stop, I thought I would increase the clearance between the two parts if possible. Using an abrasive block (Permagrit tool) I smoothed off a little of the door edge, making a gradual slope so as not to introduce a stress point. Take off too much and the edge will start to flex excessively - that edge is needed to stiffen the door. Anyway, here is where I trimmed a little off:
Anyway, that's it, door re-hung as per the previous page. The driver's side door was attended to some weeks later when some decent weather turned up.
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