Launch Tampa TTRA February 16, 2013

Crowds were smaller this week, some stayed home after checking the wind and weather predictions.
When I arrived at the Plant City launch site at 10:30 a.m.the winds were starting to pick up. Gusts were up to 15 m.p.h. with stronger winds a few hundred feet up. 

To check the conditions I first flew the Custon NOMAD with an Estes C6-5.
Even with the winds, my flights were straight up.
Under a 12" trash bag parachute this one landed 200' downrange right behind the outhouse.



This one needs explaining.
Somewhere along the way, that nose cone was severely warped from sun exposure.
I bought the Custom kit anyway and built it around the curved nose cone. The body tube was cut and angled in a slight zig-zag design.
The WARPED had a good stable straight boost with it's first test on an A8-3.
The parachute brought it down to the same spot where the Nomad landed.



Lonnie Buchanhon showed me how he's tying up shock cords and parachutes, around a plastic ring he found in JoAnne's Fabrics.
He's still testing it to see if the ring holds up to ejection stresses. The attachment held up great today.



Say goodbye to the BIG GIRTHA!

This was supposed to be a good engine combination for my new keychain camera. Two C6-5 engines gave a good boost to about 1,000 feet.
There was only a single 16" parachute and looked like it was going to land in the field. At about 500 feet up, high winds and a thermal kept it from descending. It landed somewhere in the trees to the east.
I walked through the scrubs and Lonnie B drove me to the east side of the ranch. No luck!
Fly a lot - lose a few! I should have stayed with the two B6-4s I had planned on using. Rocket, camera and video gone!

The wind gusts played havoc with a few flights. When many of the LPR birds cleared the launch rods you could see the wind gusts hit them putting a jog in their trajectory.
Bill Gibson had a Semroc Hornet go unstable with a D12-5! All we could figure was a wind gust caught it before it got up to speed.

MPC Taurus Finished

This is a pretty slick looking BT-5 sized model.
A black fin would have looked better but I didn't want to risk masking over the aluminum., or any other metallic paint.
I wish the decals would have transferred off the backing sheet, but the final results were good.

Greg Poelein's Engine Block Tip

Greg Poelein brought up a great tip recently on The Rocketry Forum:


"Here's a tip for future builds. After you fire a motor of each size (13mm, 18mm and 24mm), save the motor casing. When you get home, cut a few strips of paper 1/4" wide and as long as the sheet (11" or 14" from letter or legal paper). Put a thin layer of glue on one side of the strip of paper and wrap it around the rear of the motor, building it up to several thicknesses. Let dry.

Once these are dry, you have the perfect motor thrust ring insertion tool. Put a bit of glue on a stick and put a ring of glue inside the body tube where the thrust ring will end up. Put the thrust ring in the back of the rocket and push it into place with your insertion tool. This will insure that the motor always extends out the back of the rocket by 1/4". You can add a motor clip if you want to using the same spacing - the slit for the motor clip will be just behind the thrust ring."

This is similar to a product that FlisKits offered called "The Block and Tackle".
A great, simple idea.

MPC Taurus - 1 Build Part 10 Decals

I didn't want to do another mask for the white under color of the roll pattern.
A piece of white (sprayed) decal paper was cut into a rectangle, long enough to do a full wrap around the tube.
TIP: Notice I set the white wrap "decal" about 1/8" down from the top of the body tube. This exposes a band of the aluminum paint and gives another color separation without masking.
Below the white wrap is a piece of paper divided into fourths for a marking and positioning guide. Pencil tic marks were lightly drawn on the dried white decal.

My favorite self adhesive trim material is Contact paper for blackboards.
Strips the correct width and length were cut with a straightedge and razor blade.






The pieces were lifted with the tip of my hobby knife and positioned over the pencil lines.
Don't burnish down the pieces yet, wait until everything is in place.








Two final horizontal bands were set over the vertical strips.
As mentioned in an earlier post, be sure to overlap the band ends. They could shrink up over time.

Check all pieces for straightness and burnish down. Be careful not to scratch the white decal surface.

MPC Taurus - 1 Build Part 9 Paint and Decals

I would have liked to paint the rocket like the face card, silver with black fins.
Masking any metallic paint can discolor the metal finish, so the fins won't get a shot of black. The booster tubes will be black.
The nose cone is gloss red.
This is my favorite part of the build, when all the prep work comes together.

The roll pattern decals got a coat of liquid decal film. These decals are old and I wanted to insure they would transfer easily.

These roll patterns all have a white undercoat.
Four colors -  red, aluminum black and white should be more than enough on a model this size.

Even after coating the old decals with the decal film, they wouldn't release from the backing paper after soaking in water!
I even tried rubbing off the paper backing thinking I could just glue the decal on like a wrap, but no luck.
I'll have to improvise, this model really needs a roll pattern below the nose cone.

Wet Sanding Thoughts

I've read a few forum posts where new builders talked about wet sanding.

That piece of 400 grit (wet/dry) sandpaper in the glass of water is only about 2" X 4" in size. That one piece should be more than enough to fully wet sand a Big Bertha sized model.
You can leave that wet/dry piece of sandpaper in that water glass overnight if you wanted to - it's waterproof! It's a good idea to let the sandpaper sit in the water a while before sanding. You'll want it saturated so it won't load up with sanding paint dust.
Shake off the excess water, sand a bit then rub some of the "mud" off the sandpaper.
Keep the sand paper wet, and paper towels handy to catch drips.

Don't wet sand Carpenter's Wood Filler! Dry sand CWF.
CWF does not seal the wood. Even after it's dry, it's still water soluble.
Only wet sand parts after they have a good coating of primer or color coats.
If there is any brown body tube or balsa peeking out on a painted part, water will be absorbed, The open, unsealed area will swell up!

If you've seen my primer sands, I tend to dry sand the primer back down to the surface, especially on body tubes.
When I wet sand between final color coats, I'm only knocking off the top of the coat, just taking off the roughness and dulling up the surface a bit.

Here's my typical finishing order:
1. Fill balsa grain and body tube seams with diluted CWF. Mix Ratios are HERE
2. Let dry, then dry sand with 400 grit. (Sanding dried CWF does not load up sandpaper)
3. Spray gray primer/filler coat. I tend to lay down only one coat (heavier than others might) and dry sand to surface. (The gray primer will load up sandpaper) Clean off loaded sandpaper HERE
4. Check and prime again if needed. (Not normally needed)
5. Gloss white coats follow. Two light coats, then wet sanding. The two light coats will have sealed the surfaces so you can wet sand.
6. One final heavier, "wet" coat. This can give you a great gloss without the need for Future acrylic later.
The last coat goes on heavier, but not thick enough to run. Hold the can closer to the model and move a little slower.
Best results of a applying the heavy last coat comes with practice!

Always take your model outside and check out the finish under direct sunlight. You'll see any imperfections better outside than you ever could under indoors.

MPC Taurus - 1 Build Part 8 Undercoat Paint Mask

The "booster tubes" will be painted separately and glued on afterwards.
A thin line of masking tape was set down just short of the top of the booster tube length.

The model was set down a 1/2" dowel for a painting wand.
The entire model got a coat of white.

The face card shows the body in silver.
Black and white fins would look good against the silver body tube. But masking tape over any silver (or aluminum) paint could discolor the silver. On to Plan 2.