Tail Spin: Metal Work – ‘Playing The Percentages’
When admiring the perfectly flat bodywork and highly polished, killer paintjob on a show car, people generally don’t realise the effort that’s gone into achieving it. It begins with getting the metal work as close to perfect as possible. After all, it’s called metal work for a reason – it’s done with metal, not filler!
The easy option is to just overlap metal joins but then you end up using 2mm or 3mm filler. Over time, just a very slight shrinkage in the filler will leave a ring around the join which is visible because the mirror finished paintwork (as opposed to the ‘orange peel’ finish on a road car) shows up absolutely any imperfections. It needs to be done properly by butting the joints together, as we’ve done on Tail Spin. Then you’re talking about only needing less than 1mm of filler and I don’t believe you would see any shrinkage in that.
The second factor is getting exactly the right percentage of hardener in the filler – if you don’t get an even amount, each batch of filler dries at different rates. Therefore, if the filler work is done over three or four weeks, especially in cooler winter temperatures, some filler jobs will be 100% set while others might only be 80%. What I do is read the product instructions and choose the exact recommended percentage of hardener to use in every mix. Then I put the mixing board on the scales, zero them, add the filler and weigh the hardener as a percentage of the filler amount I’m using. It’s difficult to do in a collision repair workshop because it takes time but, for a show car, it’s about not cutting corners. I do it for all my two-pack products from filler, primer and polyester filler right through to the final clearcoat. If you don’t mix all these two-pack products as per the specifications, you leave a greater chance of issues down the track. My ‘66 Mustang, ‘Sweet Sixty-Six’, is a perfect example. It was painted seven years ago and it still looks as good as the day it was done – the way the clearcoat holds it shine still blows me away!
- PPG colours set the trend at Summernats 28
- Tail Spin project – Heavenly body design, with Howard Astill
- Protecting Bare Metal – Howard Astill