Here's the rear of the main body tube after primer filler was shot.
I didn't bother with Titebond M&TG fillets on the launch lug sides.
This area will be covered by the jet tubes.
The bottom of the jet tubes didn't get primer.
The bottom was left "naked" for gluing later.
When the primer was sanded down I noticed a shallow crimp in the body tube.
The crimp wasn't bad but might get deeper after a hard landing. I decided to reinforce the tube with an internal coupler.
I can't insert it from the rear, there's already a coupler joining the two tubes.
It will be slid in place from the top using and engine casing over a dowel.
Glue was applied in the tube using a dowel.
After the coupler was in place the excess glue was picked up with a Q-tip taped to a dowel.
Hopefully when the next coat of primer is sanded down, you won't see any crimp.
Chris,
ReplyDeleteHave you ever seen this? I'm guessing back in the day this was not the process for catalog rockets.
http://www.oldrocketforum.com/attachment.php?attachmentid=6886
Hi David,
DeleteI've seen the article before, I think it was in Sport Rocketry.
I knew that years back, catalog and trade models were built using basswood. Easier to fill and a lot stronger. Early on the catalog models were made from balsa. Check the late 1960s Estes and Centuri catalogs, the model surfaces were heavily airbrushed.