revhed wrote: ↑
Thu Nov 07, 2019 9:59 am
Foil wrote: ↑
Thu Nov 07, 2019 9:09 am
water sheen tested
using wet paper to remove sand scratches
Nice info, would you mind explaining in much more detail your "water sheen test"
what grits of wet sand paper are you using please.
Same for wings and STRUT?
There are two ways of achieving this,
The full on, no corners cut method which delivers a ride which simply can't be bettered, shockingly smooth, allowing you to push to maximum speed.
Or the more simple but not quite as good way, still delivers a great smooth ride but I can tell the difference
The full on way-
Strip off all the original paint and transfers using 120 grit wet paper wrapped round a sponge sanding block, this takes maybe a full hour or more and I use up around 2 full sheets cut into 8 quarters,
Then using 180 grit spend 20 mins fine detail sanding
Wash well, dry well and keep the wing warm, I use a small hair dryer
Using strong light and magnifying glass inspect the carbon surface, sit down as you may be shocked at the amount of tiny pin holes you might find, 50 or 100 pin holes that need filling with glass finishing compound, this stuff drys in 10 minutes on a warm wing, is cheap and easy to apply with a old plastic store card, just ensure the pin holes are dried out first and you smear the glass finishing compound over the surface as thin as possible.
When dry smooth out with 600 grit wet paper, look closely for missed pin holes and stand back to admire your spotty looking but super fine finish wing.
Next step is to add the Matt black top coat.
This is the easy part, but using the right paint is the trick here to ending up with a very tough and easy to maintain great looking finish.
Find this stuff from you local automotive paint shop, it's better than anything we have found before, and cheap which is great as well, get your grit paper from here as well,
This sprays on like a dream, covers any imperfections (but not pin holes)
Drys quickly in a warm garage, 6 -10 hours later and it's ready to fine sand, leaving it overnight is maybe better but I find sanding is much easier in the less cured stage,
Start with 800 grit(or 600grit if left overnight) wet well and use even smooth strokes front edge to back edge and back, clean and dry often to inspect the finish.
When satisfied with a your very even and fine finished surface then change to 1200grit paper, lots of water needed to stop the paper snagging the surface(using the hard sponge sanding block for all the sanding down jobs is important) regularly wash and dry the surface to check for the final almost silky Matt finish all over.
Finally finish the trailing edge angle with 800 or 600 grit paper wrapped around a small wood block, as a guide 3-4 long 30deg full length strokes on each side finally followed by 2 full length 90deg strokes to blunt of the edge, run you finger down the edge gently to check for perfection and for safety as you don't want a razor blade edge.
To test for water sheen-
Wash your hands well
Pick up your perfectly clean and dry wing
Take your wing to a water tap set on medium to slow flow
Hold your wing with fingers not on the surfaces but on the edges
Starting from the front edge uppermost run the water flow over the wing from one end to the other, with the aim of getting the water to stick completely to every part and for a few seconds to resemble a full wet gloss finished mirror surface,
This will reveal any small areas not up to standard
Take the wing over to your sanding bench and just fine finish a little more in that area, then water sheen test again, repeat until perfect.
Not sanding off all the paint and transfers is doable if the wings are in new condition and don't need minor repair work, going in with 600 then 800 grit wet paper gives a great finish
Do not expect paint primer or any spray paint to cover the pin holes you will find in carbon, you would need to drown the surface in paint to do this and that will be detrimental to the wings profile and performance
Using standard spray paints other than the one shown above is possible but you may get undesirable paint surface reactions, crazing is annoying and once found then you have a big problem than may then mean you need to strip all the wing bare down to the base carbon and start over with the right paint as shown above.