Glue not sticking to sooty body tube
 

I have a rocket that I had to replace the shock cord mount - on a previous flight the ejection charge was way too powerful and ripped the mount right out of the tube. I made a replacement, and installed it, flying the rocket today. Unfortunately at ejection the replacement mount gave way and the rocket tumbled to the ground, suffering substantial damage. When I recovered the nosecone + parachute assembly, I was surprised to see that while I had indeed been generous with the glue, that the soot on the inside of the tube kept the glue from bonding with the body tube cardboard.

Is there a good way to clean the inside of the tube well enough to get the glue to stick? How have you guys handled this kind of situation? Thanks. :)

I have had this happen a few times.

I take some course or medium grit sandpaper, wrap it around a 1/4" or larger diameter dowel and sand the sooty area until I see nothing but brown paper.

I glue the shockcord anchor in that locatiion.

That would make sense. :) I don't know why I didn't think of that. Doh'

Ditto. Yeah, that ejection grime, if not cleaned out, makes it very difficult for anything to stick.

Earl

I actually have a couple of sanding rods where I have taped sandpaper grit side out to dowels. Originally for sanding piston tubes during competition and also handy on body tubes and engine mounts. Handy for cleaning clips too. Just roll it up tight and when inserted let it unroll to fit the diameter.

Chas