Troy, I can't see much fault in your methods, except the 42" spline is
necessary only for guaranteed Best in Show at Oshkosh. That can take
forever. But to speed up --
If your splines are not padded with foam (padded spline sands quicker,
but it sands into low spots - no net gain timewise), then black paint
isn't necessary. Just watch where the dust doesn't move as the spline
passes over. I circled that area with a yellow hi-liter.
A 12" drywall knife a) may not have a flat edge (drywall tape - easier
vs. a flat knife), and b) can only be used chordwise. I found
12" and 24" pro type "masking" tools used in interior painting.
They're very flexible strips of SS sheet, mounted in somewhat flexible
plastic handle. It will bend enough when swiping SuperFil spanwise,
so you can then swipe in both directions, meaning fewer cycles of
fill/sand. Alternatively, a c. 3" wide strip of 4130 will work too,
with a cleaned up edge. It's important to add no more filler than
necessary to avoid creating high spots, and thus low spots that
weren't.
SmoothPrime will show up the imperfections, and you can apply thin
SuperFil to sanded primer. But the primer is not the best way to fix
errors, as the difference in sanding ease leaves you with waviness.
Thus it's best to get the SuperFil as perfect as reasonable. Your
hand can feel any waviness to a few thousandths. I used a magnifying
glass or hood to note any zits, scratches, and thin layers not faired.
I swiped on SuperFil as I inspected, using a small knife. Very bright
shop light helps too.
Especially for the final passes, remove all dust with alcohol. Any
residue dries out the SiperFil removed from knife and reapplied. More
imperfections result, and on and on we go...
In final gloss finish, mild waviness will be hard to spot. Other
imperfections, yes. Frustrating work at times, but comes to an end
eventually.
Regards,
Fred F., A063
Troy Maynor wrote:
>
> Hi All You Classic Builders
>
> I am in the middle of filling the classic wing. I know, I'm probably the last
> one in the field that still hasn't done this. But never the less I have some
> questions for those of you that have done this. It seems the more low areas I
> fill in the more others show up. I am using a drywall knife of about 12
> inches wide to spread the Superfil. (The widest one I could find.) I used the
> fishing line method. The sanding splines are 42 ", 24", and a short 12" one.
> All are 4" wide. On one surface I tried using some black paint to reveal low
> areas but these still are visible after more filler has been applied over
> them, confusing the next sanding/filling phase. How did some of you guys get
> those perfect finishes? How much of a mistake can be hidden with the Smooth
> Prime filler? It's too late when you have the paint on it. (I'm still "gun
> shy" after trying to prep a car for paint a few years ago.)
> HELP
> Frustrated in NC
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