The body tubes got the standard CWF seam fill and sanding.
On the left is the rough cut body tubes joined by a coupler. The tube cuts aren't great. True it up with a sanding block.
The picture on the right shows the new joint after sanding the ends with a block.
Here's the body tube after the CWF and sanding, then filler/primer and sanding.
You can see some of the gray filler/primer left in the tube seams. The filler/primer fills any recesses left after the first CWF step.
On balsa fins - I prefer a two-step CWF, sanding then filler/primer and sanding over four applications of sanding sealer and sanding.
The body tube will look mottled after sanding down the filler/primer. Most tubes are not perfectly smooth.
Here's a good example of filled balsa.
Again the filler/primer can be seen left in some of the balsa pores.
The old original nose cone also got CWF and filler/primer and sanding.
Would you describe your process for balsa fins in more detail? I'm not sure I understand it from your description.
ReplyDeleteHi Anonymous,
DeleteI start with Elmer's Carpenter's Wood Filler:
http://modelrocketbuilding.blogspot.com/2010/09/carpenters-wood-filler-mix-ratios.html
Sand that to surface using fine sandpaper.
Follow with Duplicolor Filler/Primer (FP101):
http://modelrocketbuilding.blogspot.com/2015/08/what-kind-of-primer-filler-do-you-use.html
And using fine sandpaper, sand to surface.
Most people use whatever, cheapest primer/filler they can find, but those tend to be "rubbery" and very hard to sand. The Duplicolor is the best - I've tried them all.
I use a fairly fine 320 grit to remove most of the filler then follow with 400 grit before undercoats of gloss white.
When you spray the white there might still be some rough spots, those are smoothed with 400 grit.
Thanks! Appreciate the extra detail.
ReplyDelete