I had to clean the oil strainer on the Super-Dream, and fit a new clutch today. This meant i had to take the primary drive cover off. Only problem was that I couldn't find any one that sold individual gaskets, and when Tef took me to the local car spares shop for some propper gasket paper, they hadn't got any. So Tes said to use a Cornflake packet!
I had heard of this, and thought it was a real 'Bodge', but tef assured me that done 'properly' its actually a well renouned 'improvised repair', and used to be one of the first things aprentice mechanics were tought... so here goes! My firat attempt at making my own gasket from paper... or Cerial packets!
You will need:
A cerial packet! Apaently cornflake Pakets are best, but we aren't that posh, but we this girl was undaunted. I had my Wheetabix this morning! LOTS of them! I needed the empty box! Has to be bigger than the cover or whatever you are making a gasket for BTW.
A hammer to make a 'rubbing' of the cover to get an impression to cut to on the paper.
The screws or bolts that hold the cover on, so that you can hold it in place while marking & cutting
A craft knife or two
Pair of scissors
Tef says START WITH THE HOLES!
Placing the cardboard over the cover, find one hole, and mark it with a screw, pushing through the cover against the paper. Tef says DONT get carried away. You start with ONE hole, and get it 'right'.
So you cut a SMALL cross in the paper, then push a screw through and cut the feathery bits it pushes up, off, cutting against the screw. Its a lot easier and more accurate then trying to cut a circle free hand!
You start with the holes, because, they are the awkward bits. He reckons lots of people... like I tried to.... start by cutting the outline first, then the big gap in the middle, then try punching the holes through and find they tear the gasket and have to start all over, or they get the outline all out of shape!
You start with the holes, cut one, get it good, then line the paper back on the case and do another RIGHT on the other side of the case to get the paper lined up... THEN you can go round and mark the other holes, and cut them.
With all the holes done, you can then use the screws to hold the cardboard in place, to stop it shifting around and giving you a distorted outline, while you rub the hammer over the shiny side of the cardboard, to get an impression of the outline on the soft side.
With the rubbing 'done' you can then start cutting the outline. In the case of the Super-Dream / Benley engine, there is a niggly oil gallery in the casing.
Tef said start by cutting the smaller apertures first, as the more paper there is around them, the better supported they are, and the easier it is to make them accurately, and not tear the paper.
Cutting with a craft knife, often wont go all the way through the paper, and pressing harder, can risk cutting into the bits you want to keep. But once you have got the like you want scored, you can normally work it through from the other side, to pop out the unwanted bit. But don't cut too thin! Don't worry about making it exactly accurate, working off the case, just rough out the middle you want to take out, but leave a little trim space to take off to neaten it up 'on' the case.
The aperture can be trimmed accurately to follow the case, 'on' the case, pinned down again with the bolts to hold it steady
Then the same process can be repeated to take out the larger sections or apertures.
Care is needed on thinner sections, where there is a lot of space between the bolts holding the paper to the case, or there is a complicated shape.
In these places, best to hold the paper to the case, either side of the blade, being careful of your fingers!
With all the internal areas cut out and trimmed, with the paper pegged down on the case again, FINALLY the outside can be cut to shape.
And here it is. One Cornflake packet gasket, all ready to seal the primary drive cover on the engine!
This is a first class, bit of budget mechanics! One bit of waste packaging and ten minutes work with a scalpel!