At the 2019 Stoneleigh Kit Car Show, I was looking at the various powder coat colours on the ElectroStaticMagic stand. I had been contemplating coating a few pieces in either a candy blue or red which would be similar colours to the anodised aeroquip style hose fittings that we plan to use for plumbing Project Snake.
My original thought was to go for a blue candy colour but they didn't have any in stock at the Stoneleigh show so I went for candy red instead (always one for sticking to a plan). The candy powder is applied over the High Gloss Chrome powder and I picked up 1/4kg of that at the same time.
The first pieces I decided to apply to funk treatment to were the front axle dust caps. These got the usual wire brushing, sandblasting and Afterblast treatment prior to coating.
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| Dust Caps - after initial clean... |
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| ...after sand blasting |
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| ...and after application of Afterblast |
The instructions for appying the candy powder coat require an initial coating with the High Chrome powder, which is then cured for 30mins at 180 degrees and then allowed to cool to ambient temperature. The red candy powder is then applied over the High Chrome and cured for 10mins at 180 degrees.
The dust caps were given a once over with the Eastwood Prepaint Prep and a wipe over with a tack rag and then the High Chrome powder was applied. This goes on as a flat medium grey colour.
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| High Chrome powder applied |
These were then brought up to temperature in the oven and cured for the recommended 30mins. The finish of the High Chrome is very good. The powder cures to an almost chrome-like finish (as the name suggests....). If leaving the parts as the Chrome finish it is recommended to gloss clear coat the parts to prevent the powder dulling with time. I reckon this would give the parts a really good shine and, on a well-prepped surface (unlike my battered and bruised dust caps), I think at first glance it would be hard to differentiate the finish from a real chromed part.
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| Shiny Dust Caps - shame about the dimples... |
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| I can see my face in this one! |
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| Its like looking in a battered mirror.... |
Next step was to apply the red candy powder. I did this the day after applying the High Chrome so obviously the parts had cooled completely. I gave them another wipe over with Prepaint Prep and a tack rag and then tried to apply the red candy powder.
Note the word 'tried'. This proved quite tricky. The second coat of powder didn't want to adhere to the parts at all. I'm not sure whether I wasn't getting a good ground contact (because of the first coat), although I had scraped a bit of the coating off on the inside where I had placed the hanging/ground wire, but the powder went on in a very patchy manner and when I tried to fill in the gaps, the powder that had coated the part just seemed to blow off.
I ended up blowing all the powder off with an airgun, re-cleaning the parts and trying again. The second time I turned the air pressure on the powder coating gun down a bit (to around 4psi) and trying to 'fog' the parts in powder. This did achieve a better coverage (although not a very economic use of powder and everything in the garage now has a slight red tinge to it....) although care was still needed not to blow the powder off in places.
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| Eventually managed to get parts completely covered... |
These were then popped in the oven at 180degrees / Gas mark 4 for 10mins after the parts had reached curing temperature. I was quite pleased with the results. The final colour is quite a deep red and so is more like the colour of 'Ruby' (the AK demonstrator that is current inspiration for this project) which is fine assuming we don't change our mind on the final colour!!
Close inspection of the final pieces did show some areas where the coating was a bit patchy, but only if you look closely (and the dust caps will eventually be hidden anyway - which begs the question why did I bother...).
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| Freshly cured Candy Red dust caps... |
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| Final result - some minor blemishes!! |
Still, it was a good experiment for some parts which might be more visible and so buoyed by the initial success I attempted to powder coat the rear wishbone spacer tubes.
These needed a good session with the angle grinder and some flap wheels to clean off the surface pitting caused by my leaving them too long in a citric acid de-rusting bath previously. After an intensive session with 40, 80 and then 120 grit flap wheels, the tubes cleaned up quite nicely.
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| After some flappy wheel treatment... |
These then got a final sandblast, spray with Afterblast and a clean up before powder coating with the High Chrome. As before these were cured at 180 degrees for 30mins.
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| Chrome coated spacer tubes |
Having scoured the internet for some tips on applying the candy powders, I found a couple of tips on various forums, which suggested that, rather than trying to apply the candy powder to a cooled part, it should be preheated to around 65-75 degrees to aid adhesion of the second coat.
This technique made a big difference and the candy powder seemed to adhere much more readily to the chrome coat, although there were some areas that needed a bit more persuasion than others.
However, after curing and cooling, I was a bit disappointed with the results. The candy coat was still quite thin and patchy in places and where I had obviously not managed to remove all the surface blemishes from the tubes with the grinder/flap wheel combo, the powder had concentrated around these giving some very obvious dark spots on the coating.
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| Patchy coating... |
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| ...and dark spots |
I know these tubes (and the dust caps) will be hidden from sight once the car is finished, but I still want these bits to be the best finish that they can be. So at some point soon, I will probably attempt to redo them all.
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