Some twenty years ago 'ANA' was re-finished in the original 'Yellow Gold' colour by a friend in the motor-trade. I had struck a deal with him to do this in return for my taking the photographs at his son's wedding. He did a reasonable job of the the body (he did not do the engine bay) but I noticed a couple of years ago that a rash of 'blisters' on the wing tops was starting to appear in the cellulose finish. These were not not caused by rust as the wings were replaced with new at the time and the car has been stored in a dry garage since then.
After some research I have found that these can appear years after the paint was applied. Apparently water trapped in the paint layers can expand under cold or hot conditions causing these blisters to crack open the paint surface. Moisture in the paint at the time of spraying can lie dormant for years until it is exposed to temperature/humidity conditions where it expands ruining the otherwise good finish. A word of warning 'ANA' was stored outside during the winter whilst we rebuilt the engine and front suspension a couple of years ago and covered with a waterproof 'car cover' .....the cold moisture conditions under this 'cover' would seem responsible for the 'blisters'
I had never been too happy with the finish of the roof which looked as if a 'rushed' job had been done with a poor gloss finish. This together with scratches on the doors and boot-lid acquired over the last twenty years I came to the conclusion to re-paint, despite looking cosmetically reasonable to a superficial glance...(the car I mean not me) :)
After some experience doing the inside of the boot and engine bay previously I decided to have a go at a re-paint with cellulose.
A word of warning if you are thinking of using 2 pack paint. Deadly isocyanates in the paint are not really for the DIY enthusiast - it can kill you. Even the use of a full carbon-filter mask will be as much use as a chocolate fire-guard, as the professionals use an air-fed 'helmet' complete with gloves and overalls as isocyanate can enter the bloodstream via the eyes and skin.
So cellulose was my paint of choice.....using a professional twin filter mask. I had previously used a cheap gun with reasonable results so I decided to invest in something around £60 and learn how to use it properly.
As most people will tell you preparation is everything and I spent most of last winter flatting the paint work with wet and dry paper through various grades from 240 through to 1200 grit.
Both windscreens were taken out and all the removal panels such as doors, bonnet and boot-lid removed until I had a car shell on wheels. A thin (3mm) white coach-line was removed to be replaced eventually with an identical one as applied originally in the factory.
Armed with my new spray-gun I decided to make a start - I had fitted a pressure gauge between the airline and the gun to fine tune the pressure from the compressor. Compressor also has a pressure gauge but knowing the final pressure to the gun is useful to say the least.
I found that adjusting the pressure before spraying the best way to go........initial 'set-up' of the new gun showed that the 'material' (paint) adjustment screw was too far out (rich) giving a thick coat that started to 'run' immediately. With much a trial and error I experimented until the spray pattern and paint delivered seem to be just right and I proceeded to hone my non-existent spray-painting skills on the underneath of the bonnet. After the gun was set-up I left the adjustments as they were. If it is working - don't try to fix it - is always a good maxim I find.
One bit of advice I learnt the hard way, was to try the gun on a sheet of masking paper every time before starting on a new panel. I did not do this when starting on the all important top of the bonnet ( hood to any American readers) and the paint came out initially in 'globs' perhaps caused by not cleaning the gun properly between uses. A few trial runs over the paper had things back to normal much to my great relief. There are many articles and videos on Google and YouTube by experienced professionals that are worth watching to learn the basics of cellulose spraying, but like most things in life I find that actually 'doing it' teaches you more than any video. One thing I did learn from YouTube is that amongst the guys who know what they are doing there are a few who make a pig's ear of the job..........so be careful who you copy.
After some research I have found that these can appear years after the paint was applied. Apparently water trapped in the paint layers can expand under cold or hot conditions causing these blisters to crack open the paint surface. Moisture in the paint at the time of spraying can lie dormant for years until it is exposed to temperature/humidity conditions where it expands ruining the otherwise good finish. A word of warning 'ANA' was stored outside during the winter whilst we rebuilt the engine and front suspension a couple of years ago and covered with a waterproof 'car cover' .....the cold moisture conditions under this 'cover' would seem responsible for the 'blisters'
I had never been too happy with the finish of the roof which looked as if a 'rushed' job had been done with a poor gloss finish. This together with scratches on the doors and boot-lid acquired over the last twenty years I came to the conclusion to re-paint, despite looking cosmetically reasonable to a superficial glance...(the car I mean not me) :)
After some experience doing the inside of the boot and engine bay previously I decided to have a go at a re-paint with cellulose.
A word of warning if you are thinking of using 2 pack paint. Deadly isocyanates in the paint are not really for the DIY enthusiast - it can kill you. Even the use of a full carbon-filter mask will be as much use as a chocolate fire-guard, as the professionals use an air-fed 'helmet' complete with gloves and overalls as isocyanate can enter the bloodstream via the eyes and skin.
So cellulose was my paint of choice.....using a professional twin filter mask. I had previously used a cheap gun with reasonable results so I decided to invest in something around £60 and learn how to use it properly.
As most people will tell you preparation is everything and I spent most of last winter flatting the paint work with wet and dry paper through various grades from 240 through to 1200 grit.
Both windscreens were taken out and all the removal panels such as doors, bonnet and boot-lid removed until I had a car shell on wheels. A thin (3mm) white coach-line was removed to be replaced eventually with an identical one as applied originally in the factory.
 |
| Finished bonnet moved to the conservatory for safety whilst the rest of the car is finished in the limited space of our single-car garage. |
Armed with my new spray-gun I decided to make a start - I had fitted a pressure gauge between the airline and the gun to fine tune the pressure from the compressor. Compressor also has a pressure gauge but knowing the final pressure to the gun is useful to say the least.
I found that adjusting the pressure before spraying the best way to go........initial 'set-up' of the new gun showed that the 'material' (paint) adjustment screw was too far out (rich) giving a thick coat that started to 'run' immediately. With much a trial and error I experimented until the spray pattern and paint delivered seem to be just right and I proceeded to hone my non-existent spray-painting skills on the underneath of the bonnet. After the gun was set-up I left the adjustments as they were. If it is working - don't try to fix it - is always a good maxim I find.
 |
| Re-paint for my HC Viva in the original 'Yellow Gold' |
One bit of advice I learnt the hard way, was to try the gun on a sheet of masking paper every time before starting on a new panel. I did not do this when starting on the all important top of the bonnet ( hood to any American readers) and the paint came out initially in 'globs' perhaps caused by not cleaning the gun properly between uses. A few trial runs over the paper had things back to normal much to my great relief. There are many articles and videos on Google and YouTube by experienced professionals that are worth watching to learn the basics of cellulose spraying, but like most things in life I find that actually 'doing it' teaches you more than any video. One thing I did learn from YouTube is that amongst the guys who know what they are doing there are a few who make a pig's ear of the job..........so be careful who you copy.
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