Custom Solar Explorer Build Part 8 Filling Tube and Lug Seams

I've noticed that the narrower the body tube seams is, the CWF stays in better when sanding.
I have the best luck using a slightly thicker mixture of CWF on the body tube seams. When it's thicker, the glues aren't watered down as much and the filler seems to stay in the seams.

I've been dabbing the filler onto the seam with a cheap brush.
Apply the CWF on the seam for a few inches, then remove the bulk with a razor blade. Wipe the excess CWF off the blade between removing the filler.

I'm not trying to remove it all with the razor blade! Notice how much is left on the tube. Don't pull out the filler you just applied in the seam.

The top tube shows the filler after drying.

The bottom tube has had the filler sanded to surface with 400 grit.
For me, I never have to use any rougher grit than the 400 to remove the filler.

A 220 grit would take it down faster but would also leave deeper scratches in the tube. Deeper scratches means more primer and more sanding.

When the bottom tube is sanded to surface as shown, I only do one (slightly thick) coat of gray primer.
That gray primer gets sanded with 400 grit and is then ready for the first white undercoat.

I've read where some builders do two fill coats of  CWF then four coats of gray primer. That, and all the sanding between every coat! That seems like a lot of extra work. This is what works for me. Everybody has their own way to get it done.


I also fill the lugs before gluing them onto the body tube.

TIP: A simple holder for brushing on the filler is three toothpicks held like a rounded triangle.

The tapered ends of the toothpicks give a good friction fit of the lug ends.