A raised glue bead was applied to the outside of the ring with a toothpick. I didn't really smooth the glue, it was left to dry and shrink covering any rough edges.
Thursday, September 30, 2010
Semroc Little Joe II Build Part 18 Tower
A raised glue bead was applied to the outside of the ring with a toothpick. I didn't really smooth the glue, it was left to dry and shrink covering any rough edges.
Semroc Little Joe II Build Part 17 Tower
I actually had to do the "V" strut assemblies twice to get them right!
Wednesday, September 29, 2010
Semroc Little Joe II Part 16 Tower
One thing I learned after the tower sides were glued - every other "Z" diagonal brace side should be reversed as shown in this drawing. (Click on the drawing for an enlargement)
The "Z"s on my tower all face the same direction. Most people wouldn't even notice.
It's only after I looked at some scale drawings that I noticed the change in the "Z" diagonal bars.
The tower viewed from the back shows some of the gluing.
When first gluing the tower sides together, I don't use much glue. This way it's easier to make some adjustments if things aren't right. If all placement is good, I do heavier gluing like shown in the picture.
Tuesday, September 28, 2010
Wolverine Downscale "How To" Part 2
It's repeated here for the benefit of a younger builder or anyone curious about the process of downscaling.
If you are new to the hobby, you might find yourself spending too much time at JimZ's plan site.
You'll find it HERE
The Wolverine instructions are there - click on the Estes logo and scroll down to the Wolverine, plan #0816.
The fin plans are included, but I couldn't get them to print at the correct size. They were way too large! Some plans have a 1" square for reference, this drawing didn't.
A quick post on TRF got me the fin dimensions for my size reference.
Thanks to John Brohm for measuring the fins right through the kit bag!
I wanted to downscale the model from it's original BT-50 to a BT-5 main frame.
Normally you'd divide .543" (BT-5 downscale diameter) by .976 (BT-50 original diameter) to get a downscale factor of .56.
TIP: Using the Scale Factor Charts found HERE
I reafirmed my factor to be .56.
All the original measurements would be multiplied by .56 to get the smaller model dimensions.
Thanks to Jay Goemmer for putting together these valuable charts!
Semroc Little Joe II Build Part 15 Tower
You should use waxed paper under the glued dowels. I took this picture without it for clarity.
I don't use a heavy glue blob over all the strut joints. I'll apply a small drop and wipe off the excess. This pushes glue into the joint and around the joint closing up any cracks. To do it right, you'll have to apply glue a few times because it will shrink.
Sunday, September 26, 2010
Bad Estes Instruction Drawings
Who can forget the talented "Talking Paint Brushes" from the old Estes Saturn 1B instructions.
The "Evil Eye" lines up the tailcone marking guides
A personal favorite and source of nightmares, some of the suggested paint schemes from the Astron Spaceman kit.
That top row, middle drawing has Eddie Cantor's eyes.
Estes Saturn V Instructions
Friday, September 24, 2010
Semroc Little Joe II Build Part 14 Tower
Take a close look at the Semroc tower pattern.
With a pencil and straightedge I've extended the cut lines past what was printed on the pattern.
This makes cutting the dowel length and angles easier. You can't see the cut lines if the dowel is sitting on top of them.
Keep track of how many pieces you've cut. If you aren't going to do be gluing up the tower right away, keep all the pieces in a Ziploc bag. They are small and too easy to misplace.
I did all the cuts using a single edge razor blade. Line up the thin blade over the extended pencil lines you drew.
Note: The lower "V" struts are a little longer than the upper "V" struts.
If you enlarge the picture, you can see the sides were glued together before cutting off the top of the "V".
The sides were allowed to fully dry and the "V" was held steady over the template. A razor blade was set directly over the exteded pencil lines and the tip was cut off.
Semroc Little Joe II Build Part 13 Tower
Thursday, September 23, 2010
Estes Wolverine Downscale "HOW TO" Pt.1
I had a great time downscaling all the GooneyBirds, Sky Writer and A20 Demon.
Through these series of posts, you'll see the process to do the art for making a downsized "carded" model rocket.
The carded models I've made require very little painting. You print out body wraps and glue them to the appropriate sized tubes. These are stronger than the usual rolled 120 lb. card stock models. The fins are a printed ply "sandwich" folded over cereal box cardboard.
The nose cone on this model is balsa. It's the only part needing filling and painting.
To me it doesn't look like a downscale unless the finished model is about half the size of the original. It wouldn't really be a downscale to go from a ST-10 to a BT-50. It's too subtle of a change in diameter and length.
The Estes Wolverine is an interesting candidate for downscaling, Larry Renger was the designer. It was kit #0816 available from 1973 through 1979. Powered by a "T" engine model it had a BT-50 airframe. A BT-50 is on the large side for a mini engine power. This downscale will be BT-5 based and could fly with anything from a MMX to an A10-3T engine.
Semroc Little Joe II Build Part 12 Command Module
Here you can better see how the rings roll off with a rub of your thumb. Follow up with a angle sand with a sanding block and it matched up with the shroud very well.
Semroc Little Joe Build Part 11 Capsule Parts
Here's all the capsule and tower parts.
The two balsa ends of the escape tower motor unit are one piece and are cut apart. You aren't told to cut them apart in the instructions, but the illustrations in Step 2 show them as two pieces.
The Command Module nose cone is different from any other kit I've made.
The large cardstock sheet has the shroud and templates for cutting and gluing of the tower.
Semroc Little Joe II Part 11 Apollo Capsule Kit
Wednesday, September 22, 2010
MMX Igniter / Toothpick Debate
Apparently, pushing a round toothpick in a round MMX nozzle could lead to overpressure and possible explosion of a Micro Maxx engine. The toothpick shouldn't be crammed in like a plastic igniter plug used in 18mm or larger engines.
In an earlier post (click HERE) I wrote of my success using a square toothpick (instead of a round one) to hold the igniter in the small MMX nozzle. The square toothpick might allow some pressure to escape and prevent an engine CATO. Picture a "Square peg in a round hole".
Some posts agreed that square toothpicks could be the way to go with igniter installation in MMX engines.
If using a toothpick to hold in an igniter in a Micro Maxx engine, don't force the toothpick into the nozzle!
Insert the igniter far enough into the nozzle so it touches the propellant. Set a toothpick into the nozzle - don't force it in!
Once slid down the launch rod, the toothpick rests on the blast deflector. The weight of the rocket on the toothpick should be enough to hold the igniter in the nozzle and guarantee ignition.
Semroc Little Joe II Build Paint and Decals
Remember those extra trim decals I printed up awhile back? Click HERE for an example of how to make them.
The instructions say: Paint a black band 5/16" wide at the bottom of the main tube. A second band 5/32" wide is painted at the joint between the two wraps.
It'd be much easier just to use some of the black decal stripes printed out earlier. I cut some wider strips to the correct widths.
The strips were cut longer than needed. After drying, they were trimmed down by running a razor blade in the root edge and the overhang strip removed.
After trimming up, here's the lower half of the Little Joe. I'm still debating about adding a spraying on clear coat over the decals.
TIP: Clear coats over a metallic finish will turn a silver paint to a dull gray.
Semroc Little Joe II Build Part 10 Pre-Paint
To center the launch lug on the upper wrap:
Tuesday, September 21, 2010
Semroc Little Joe II Build Part 9 Engine Mount Install
TIP: To spread the glue fillet, I used a 1/4" dowel with one end sanded round. Think of it as a long, thin fingertip.
When getting the drop of glue down to the joint, try not to get glue on the inside of the body tube. Your target is the centering ring / body tube joint.
Internal construction can be as just clean as outside surfaces of the model by taking a few extra minutes to do it right.
Semroc Little Joe II Build Part 7 Body Wraps
While the instructions say to use glue to attach the wraps to the body tube, I use spray adhesive so I have a little more time to set them down straight.
In the picture you can see I've already filled the body tube seams, primed and sanded the body tube smooth. A line was drawn down the body tube for the wrap alignment.
The lower wrap was rolled into place without any problems. The match of the ends was very close.
The instructions just say to apply the wider second wrap "close" to the first wrap. I probably put the upper wrap a little too close to the lower one. Not a big deal.
This might lead to some problems with the decal and black band placement later on, we'll see.
Monday, September 20, 2010
Semroc Little Joe II Build Part 6 Fins
The square is at a perfect 90 degree angle. I'll lightly sand the fin sides until the root and trailing edges match the 90 degree angle of the square.
On a four fin model this can help the finished rocket stand on all the fins without wobbling. That is, if the fins are all glued on the body tube equally.
On a three fin model, it doesn't matter. It'll stand on all three trailing edges no matter how badly aligned the fins are.
LAUNCH! Small Stuff - September 20, 2010
Last up was the downscale CHEROKEE T with a 35 year old MPC 1/2A3-3m engine. Great altitude with a 100 yard walk to pick it up.
TIP: I've been re-using Quest MMX Igniters for some time now.
This is an MMX Igniter after today's launch, still held by the clips. That's the third time I've used this igniter. I'll keep using it until it breaks or burns through.
Semroc Little Joe II Build Part 5 Fins
Sunday, September 19, 2010
On EBAY, Martian Patrol For Sale!
You can check out the auction HERE
If this seller gets half that, mine will be on EBAY tomorrow.