Open Up and Say "Ahhhh..."

 The Thrifty Rocketeer blog continues...

A recent entry on Facebook made an excellent suggestion that we all agree is very good.  A number of people have endorsed it and said that they have done this regularly.  Perhaps we all have at various times.

The suggestion is to save the chopsticks that one receives at a Chinese restaurant and to place them in your tool box.

The idea is that many of these chopsticks are two round dowels on one end, but have a flattened opposite end that in some cases are initially attached.  To use them, you pry the two pieces apart.

The idea is that the flat end can be used as a paddle to apply glue (epoxy or otherwise) deep inside the body tube on in hard to reach places, like along the motor mount in a through-the-wall fin arrangement.

 

The original poster even suggested marking one inch increments along the chopstick, so that you can grip the stick at the right mark and know exactly how many inches you will be able to reach down into the tube.   For instance, the instructions may suggest applying glue in a circle five inches down the inside of the tube.  By gripping the stick at about five and a half inches, you can probably spread your glue at the five inch mark.

 

I have done something very similar when applying glue deep into a body tube.  

Except, instead of chopsticks, I reused an older thin wooden paint stirrer from a hardware store that had gone out of business.  The idea was to split the wood along the grain, and have a paddle or stick more than a foot long. By careful dividing, you can come up with about four of these paddles to apply epoxy deep down the throat of the body tube.

I used a similar technique just last week when I had glued the centering rings and motor mount into a Cowabunga rocket.  One of the last steps was to screw two rail buttons into the outside of the body tube, but anchor them into the wooden centering rings.  The first, lower most screw went pretty well.  But I was a bit stumped on how to determine how deep the top centering ring was, considering that I had already glued both entering rings in place.

The solution is easy enough, as long as the top of the body tube was still open.  By reaching down inside the throat of the rocket with a ruler (or in my case, a sturdy tape measure) you can measure how far down you can reach before impacting the centering ring.  Remove the tape measure and add about an eighth of an inch as you measure down the outside of the body tube.   Placing an X on that point, in line with the original rail button, you have a target for your second rail button.

It worked like a charm for me.... and I buried the wood screw into the centering ring with confidence.

Just a tip of the hat to the original poster for his simple and brilliant reminder to use chopsticks as a paddle when applying glue in a remote location.

This has been the Thrifty Rocketeer saying, "Remember to save your balsa wood scraps for repairs and fins."