Rocket Building Tips

Here are some tips on building rockets that we've learned this year.

Read and follow the directions.

Well, duh. Make it easy on yourself. A lot of instructions (including our Viking kit) have check boxes so you can keep track of where you are by checking off each step when completed.

Read all of the instructions before starting

Almost always the first instruction is to read all the instructions first before beginning. This is very useful, particularly so you understand when you are doing things in earlier steps to make things work in later steps.

Check your parts before starting

Lay out all your parts and compare them against the parts list or "exploded view". First, this let's you spot missing parts, but more importantly it helps you learn what each part is so you know what the instructions are talking about. For more complex kits, for example, you'll often have several tubes of different sizes that you'll need to keep straight.

Keep straight which end is which!

Our Viking kit calls for marking fin lines only at the bottom of the tube. We all found this very useful for keeping track of which end to put the engine block into!

Don't forget the engine block!

Most kits, including the Viking, have some kind of engine block that is glued inside the engine tube. It keeps the engine in place: otherwise, the ignited engine will shoot up the tube and out the nose code, leaving the rocket on the pad! Since you can't tell from the outside whether the engine block is in place, if you don't follow the instructions carefully, you could accidentally skip this step and never notice.

Attaching fins

Attaching the fins can be one of the most frustrating parts of building a model rocket. The key is being slow and deliberate, and following the instructions carefully. (A theme!) A good technique is described in the Viking instructions: put a thin (thin) layer of glue on the fin, then put the fin on the body along one of the fin lines as if installing it, but then take the fin off again. Now you have a thin layer of glue both on the fin and where the fin will be installed. Let this glue dry a little, about 20 seconds or so ("until tacky", they always say), then add a little more glue to the fin and really install it this time. The tackiness holds the fin in place to let everything dry.

A big key, we discovered, was not using too much glue. If you use a lot of glue, it just can't dry fast enough to hold the fin in place while you move on to install the next one.

We also discovered something called "tacky glue". A few of our members were having a lot of trouble, but the tacky glue basically comes out of the tube in that "tacky" state the instructions want, so with it everyone got their fins on fine. It seems to hold find, but we won't know whether the fins will stay on in flight until we launch them, though!

Letting the glue dry

We built our Vikings in two steps. First, we did everything up to and including attaching the wings. We stopped there to let the glue holding on the wings to dry before we continued. Then we completed the rest of the construction including reenforcing the wings with glue "fillets". This allows the rest of the glue to dry before we paint. This is a typical split in a rocket build, and with more advanced models, you may need to wait more often. My advice is not to rush it, though: it's very frustrating to carefully attach some piece only to knock it off in the next step.

In our project, we meet for an hour at a time. With the Vikings, this was perfect for those two steps I mentioned while following the instructions (almost) in order. With other models, you may need to wait for glue to dry after even small steps, so to keep yourself busy, you might need to jump around in the instructions a little to find other, unrelated things to do (like we did with the Vikings, skipping the paint step in order to finish the construction). The important thing is not to rush it, although another important thing is to make sure you understand how the steps related to each other so you don't glue yourself into a corner by skipping around. One more reason to read all the instructions before beginning.

Don't be afraid to waste spray paint

Oh, that's a terrible thing to say! But when painting with spray paint or primer, be sure to keep the spray can 6 to 8 inches away from the rocket. This means a lot of the paint misses the rocket, but it's the only good way to get an even coat. Also, plan to put on multiple coats: if you try to hard to cover everything in one coat, you're bound to get too much paint on the rocket causing drips. Just plan on putting on a coat and coming back a couple hours later for a second coat, focusing on the places you missed the first time.

Don't forget to turn the rocket to cover the tops and bottoms of the fins.