Monday, February 28, 2011

ASP Micro Jayhawk Decals

I emailed Aerospace Specialty Products and told them about the problem I had with the Micro Jayhawk kit decals.

When I built the kit the decals dissolved when they were placed in water to soak. I assumed they weren't sprayed with a clear coat after printing.

The complete micro Jayhawk build thread is HERE.

After an email, I quickly received two new sets of decals in the mail.

These decals are tiny! As directed in the instructions, let them soak one at a time.

TIP: I've learned over the years to use less water in the soaking bowl. It's easier to get them out of the bowl if the water level isn't too high.

The new decals went on without too much trouble. Because of their small size, it was easier to place them with tweezers.

While the decals weren't hard to place, I realize now why the instructions told you to offset the launch lug away from the root edge of the fin. The rear "bars" body wrap hits the lug the way I glued it. I trimmed the decal wraps to fit.

The decal edges were cut close but they didn't stay down where they touched the fin joint.

Pledge (with Future finish) acrylic floor finish was set on the lifted edges with a toothpick. It flowed under the lifted edge of the decal and held it down.

The decals certainly made a difference on the model!

I've already flown the Micro Jayhawk twice without the decals.

It's fast off the pad and very stable.
Keep your eyes on this one, it could be easily lost in tall grass.
Thanks to ASP for their quick response!

Semroc I.Q.S.Y. Tomahawk Build Part 10 Fin Prep

I decided to prime the fins off the model.

Because the primer seals the fins, the fillets wouldn't be as strong. So, a little masking was done done the root edge.

This mask would leave just less than 1/16" of raw wood above the root edge for the fillets to grab onto.

Here's the primer sprayed fins after the masking tape was removed. You can see the raw wood along the root edge.

When sanding the fins, stay away from the edge taper line. Concentrate on the flat areas of the fins, not the edges. If you sand the primer correctly, there should be some left at the start of the taper.

The primer that's left on the line will actually accentuate and sharpen the start of the taper.

Sunday, February 27, 2011

More Sales and Scout Stuff Clearance Update!

I received my bulk pack engine order yesterday!

After I had originally posted here about the clearance sale at I followed by posting the sale information on The Rocketry Forum.

While I only ordered two bulk packs of engines, many bought much more! Some were disappointed when B6-4 and C6-5 bulk packs quickly disappeared. But it's clearance sale! That's to be expected. First come, first served.

ScoutStuff doesn't email you with "up to the second" order updates like Semroc. I had ordered B6-4s from them last year and knew my order was on it's way.

AS OF TODAY, February 27, 2011
Still available from HERE are:
1/2A3-4t and A8-3, 24 Engine Bulk Packs for $19.88
B6-4 and C6-3, three packs of engines for $2.88
12 packs of Alpha IIIs, Wizards, Gnomes and Viking kits for $19.88
Shipping is $7.50 for orders up to $50.00

There's more sales out there:
Commonwealth Displays, Inc.: HERE
Commonwealth has many Out-Of-Production kits available.

And Ridge Road Station: HERE
Ridge Road Station is going out of business. Many kits and some engines are 1/2 off! Look for the Estes listing on the right.

Semroc I.Q.S.Y. Tomahawk Build Part 9 Tube Joining

I found I still had to build up more to fill the seam joint.

A bead of super glue was made on the seam. After drying I sanded it down with 400 grit on a sanding block.

Sometimes I'll use the super glue to lock the filler down on the tube or in a tube seam. While Carpenter's Wood Filler is great stuff, it can flake off or be knocked out of a body tube seam when sanding.

I realized something interesting was going on.
The upper tube diameter was just a little smaller than the lower.

Notice in the picture how the sanded filler is really only on the upper tube. I would assume these two pieces of tube came from two different "batches."

I hope it won't be noticeable on the finished model.

Saturday, February 26, 2011

LAUNCH! Schoolyard February 26, 2011

Rocket spectators, Michelle and son Jimmy had contacted me that they were going to be in town and asked if I was going to be launches during their stay. I told them to meet me at 8 a.m. before the soccer players take over the field.

Today's launch was supposed to be a demonstration for a family visiting from Norway. They were in Florida for yesterday's Shuttle launch and were interested in seeing some model rockets fly. We should have had 8 - 10 people at this mornings launch.

As it turned out, the Norway group were unable to come. So Jimmy got all the duties of countdown, launch and recovery.

Here Jimmy launches the new CORKSCREW with an A3-4t.
It had a great spiral boost, hence the Corkscrew name.

The UP! CUP had a good, stable flight with a Estes C6-3. The wind was starting to pick up and I was getting wary of drift.

A C6-3 in an odd-ball rocket is about as much power as I can fly in this small field.

A re-build of the Semroc THUNDERBEE flew with an 35 year old MPC 1/2A3-5t engine.

I can't figure out the problem, but this new build had a broken fin on landing. The last Thunderbee broke fins on two previous launches.

The Quest ASTRA III was launched twice. I prepped it on site to show Jimmy how to pack wadding, fold a parachute and install an igniter.

The first Astra III launch was with a Chinese made Quest A6-4. At about 25 feet up it went horizontal and ejected on the ground. This was the second time I've had a Quest A6-4 do this. The other was in a Semroc Astron, an otherwise stable model.

I wanted to see it fly stable so I loaded it up with a Estes A8-3. This time the Astra III had vertical boost and deploy of the reefed chute. Not a great altitude, but a successful flight.

Also flown:
A new downscale carded SKY WRITER with a MMX engine. Straight and true boost with a detached fin on recovery.

Before Michelle and Jimmy left, I gave Jimmy the (still warm from flight) Quest Astra III and a Starlight Apogee kit to build. Michelle told me he still had a launcher from a previous lost rocket.

Semroc I.Q.S.Y. Tomahawk Build Part 8 Tube Joining

In Step 12 the two lengths of tube are joined with a coupler.
1/2 of the coupler is glued into the lower tube.

Before the glue in the lower tube dried, the upper tube was slid in place, no glue on the upper half yet.

The tube was rolled on a smooth counter top then double checked for the best fit fit all the way around the joint.

I ended up turning the upper tube until I found the best match.
A pencil mark on both tubes would insure the best alignment and seam fit.

Even with the rolling, alignment and pencil marks, a prominent seam was still there.

My first CWF fill was brushed on and the excess wiped off close to the seam.

After sanding, more CWF was applied in a wider band.

Friday, February 25, 2011

LAUNCH! Schoolyard Soccer Field February 24, 2011

That's Austin, the neighborhood maintenance man.

I asked him to press the launch button so I could take some "two-handed" launch pictures.
Austin did great and seemed to enjoy his momentary second childhood.

The downscale carded PATRIOT flew on a 1/2A3-2t engine. A fin broke off on landing, an easy repair.

Here's the MicroMaxx MISSILE TOE downscale.

It's always reliable with simple nose-blow recovery. There's no room for a streamer.

The UP! CUP is back and flying stable again!
It's tailor made for a small field and flew on an Estes B6-2.

Here's a new one!
The CORKSCREW was designed by Bruce Levison. It won him the first place in the Fliskits DOM contest in October of 2003.

With a 1/2A3-2t, it did corkscrew on the way up from the offset ring fin at the bottom.

A quick build will follow the Semroc Tomahawk on this blog.

Also flown:
A new build of the downscale MMX SKYWRITER. I saved the nose cone from the original, now retired.
The ASP MicroMaxx JAYHAWK had it's second flight. This has got to be the smallest rocket in my fleet. I'm glad the grass was cut low, it'd be easy to lose.

Semroc I.Q.S.Y. Tomahawk Build Part 7 Engine Hook

I went back to the engine mount and removed the extended engine hook.

This rocket will end up with a friction fit engine.

If I'm taking the extra time to get it closer to scale, it wouldn't look right with a metal hook extending out the back.

A fine toothed razor saw was used to score the hook. I'm just cutting through 1/2 of the metal. I don't want to cut completely through and into the engine mount tube.

The hook was simply bent up and down until it broke off at the sawed score line.

The front end of the hook will remain in place. It'll never be seen once the mount is glued into the body.

Thursday, February 24, 2011

Semroc I.Q.S.Y. Tomahawk Build Part 6 Fin Shaping

When sanding up to the pencil line, I made sure the edge of the sanding block didn't go beyond the line. This way I'm just sanding up to the line and hopefully maintaining a definite start of the taper to the leading edge.

Here's all four fins after sanding the tapers.

Before going any farther, I'll paint some CWF on only the newly tapered raw wood. When sanded smooth, this new coat of CWF will help refine the taper line even more.

Semroc I.Q.S.Y. Tomahawk Build Part 5 Fin Shaping

TIP: Before sanding the taper, I brushed on a coat of CWF and sanded it smooth. I would be sanding through the CWF coat when tapering the leading edge taper. The bare wood underneath is a little darker than the light beige CWF. This gives me a contrast color while sanding and be easier to see if the taper is straight.

Using my engineer's ruler I marked the fin edge taper to a width of .21".

Two tick marks were made down the fin leading edge.

The tick marks were joined with the ruler. I double checked to be sure the width was consistant from side to side.

Because the fin thickness is thin (.050") I concentrated on the leading edge wedge taper first.

You can now see the difference in the CWF and bare basswood. It's subtle, but makes it easier to see the sanded wedge line.

Wednesday, February 23, 2011

TIPS for Tying Shroud Lines

Parachute tape disks can be tough.

You've got to weave the line through the disk and then tie a square knot.

Here's a few tips:
1. Don't touch the sticky side of the disk. The oils on your skin will diminish the adhesion.
2. Use your knife blade to hold the disk. In the picture at the left, you are looking at the sticky side of the disk facing up.
3. To give yourself just enough line to tie, the loose end should be about 3/4" below the bottom edge of the disk.
4. Use long tweezers to hold and tie the line. The work area is so small, you'll have trouble tying the knot with your fingers. TIE A SQUARE KNOT.
5. If you are making a Quest parachute, you'll have to tie three overhand knots. The Quest shroud lines have a habit of untying themselves unless you do three overhand knots.

6. Make the knot below the disk. Keep the disk on your knife and use it to position the disk into position on the parachute material.
7. Transfer a small bit of white glue to the knot with a toothpick tip.

I know, I've heard it before:
"If you tie the knot correctly, glue is not needed."
I still feel better setting the knot with a bit of glue.

Semroc I.Q.S.Y. Tomahawk Build Part 4 Fin Shaping

I've started sanding the fins to the scale thickness of .05".

When working it down to the right thickness, I only sand one side of the fin.

To be sure I was only sanding one side, I'd restart with the fin root edge to the outside.
When sanding, I'd rotate the fin, but not turn it over. I'll sand and thin it from one side and keep the other side flat and square.

Here the fin thickness is checked in the caliper. Go all the way around the fin checking the sides and middle for consistent thickness.

Here's an original 1/16" thick fin on top and the .05" scale thickness fin underneath.

Tuesday, February 22, 2011

Semroc I.Q.S.Y. Tomahawk Build Part 3 Fin Shaping

The 1/16" basswood fins are to be thinned down to .05" thick.

I'd recommend sanding the fin thickness to .05" before tapering the leading edge.

This is a piece of scrap basswood taken from laser cut sheet in the kit.
I wanted to practice thinning and sanding the taper on scrap first to decide if it was do-able before committing to the kit fins.

I locked my caliper to the .05" width and used it to check the thickness of the practice piece as I sanded.

The scrap piece was sanded down to the .05" thickness with 220 grit on a sanding block. You won't be able to get a consistent thickness without using a sanding block.
As you sand, you'll have to continually check the thickness. Stop sanding when the basswood just slides into the caliper.

Semroc I.Q.S.Y. Tomahawk Build Part 2 Engine Mount

The instructions would have you install the 24" elastic shock cord under the coupler holding the two body tube pieces together.
I was concerned about the elastic making a bulge under the body tube where it turned under the coupler.
I decided to tie Kevlar under the engine hook and join that to the elastic just under the upper body tube lip.
Looking at the picture at the right, I should have made the loop longer so the knot was above the top of the engine mount tube.

The ST-8 main airframe tube is not much wider than the ST-7 engine tube.

The way I tied it, the knot would press against the inside and make a bulge in the ST-8 body tube. I'm sure this is why Semroc decided to mount the shock cord under the coupler.

I ended up cutting a notch in the engine tube the knot could sit in. This recessed the knot and brought it in flush and inside the diameter of the ST-8 tube.

These CR-78 centering rings are pretty thin. The engine hook did raise them a bit. I sanded down the raised rings for a better fit inside the ST-8 mainframe tube.

Monday, February 21, 2011

Semroc I.Q.S.Y. Tomahawk Build Part 1 Parts

Here's the parts layout for the Semroc IQSY Tomahawk.

Of particular interest are the laser cut basswood fins.
I can appreciate Semroc using the basswood. It'll be easier to sand the wedge taper on the leading edge and keep the line sharp.

The IQSY Tomahawk didn't have any lettering but there is a small decal included with the rocket name.
I won't be using the decal, I'm going to try for "close to scale" using some G. Harry Stine drawings from the older Centuri instructions.

One thing I don't get is the two piece main body tube. The two tubes are joined by a coupler, but it still means another seam to be filled. I'm sure Semroc did it this way so it would fit into a smaller bag and be easier to hang on a hobby shop wall.
The coupler also holds in the 24" long elastic shock cord. I'll add some Kevlar tied to the engine mount and attach the elastic to that..

The full size Tomahawk was 9.0" in diameter.
This model is built around the ST-8 body tube which is .908" in diameter.
This makes this model a very close 1/10th scale.

I.Q.S.Y. Tomahawk Information

The next build will be the Semroc IQSY Tomahawk, Kit. # KD-2
This is a 10th scale model, the second in Semroc's DeciScale series.

Before we get started, check out the Harry Stine drawings at:

Or, the old Centuri instructions with the same scale information in a different format:
Scroll down to the bottom. I believe G. Harry Stine drew these also, he did the scale workup for Centuri.

I'll be drawing up the black band at the top and the bolts and panels over the fin root edges.
When I get to finishing the rocket, they'll be available as a PDF if anyone would like a copy.

Sunday, February 20, 2011

Tampa Area T.T.R.A. Launch February 19, 2011

Here's just a few of the spectators that came out to watch the rockets fly yesterday at the T.T.R.A. Tampa launch.

I've never liked the term "rocketeer".
Terry Johnson hit the nail on the head by calling today's gathering a "Gaggle of geeks".

Manuel Mejia flew his CINEROC 21.
There's a video camera peeking out the other side of this scratch built booster.

Manuel was here to cover the launch for the Rocketry Planet website. His scratch builds were just that - true scratch builds. Great builds and great fliers.

Here's a few of Brian Urban's fleet.

His workmanship is beautiful, check out the new PERSHING. The nose cone is epoxy strengthened card stock. It flew with a F35.

Astron Mike knows gliders. He builds light and consistently gets competition worthy durations with his rear-eject pod gliders.

That's my Dyna Star LEXXJET next to one of Mike's gliders before it flew with a D12-3 engine.

Today we saw blue skies and calm winds. I don't think anybody lost a model. Most everything landed close, within walking distance.
Everything was great until about 2:30 p.m.

A fast wind gust raised a few tents and sent flight cards everywhere. A few fliers tried to hold down the central RSO but to no avail.

It was a scary thirty seconds. Nobody could believe how fast the wind came up. It quickly died down and flights resumed.

Lonnie Buchanon flew some of his 35 year old rockets. That original ALPHA is from the early 1970s. Even the parachutes were from that era. He also flew a vintage Estes Citation QUASAR.

To the left of Lonnie's Alpha is my JOLLY ROGER with the "planked" fin. It flew with two parallel clustered C6-5s.

Joe Lapore's WARHEAD rocket loomed over the site throughout the day.
Although I didn't see it fly, it was an impressive scratch build.

This last picture is another glider from Astron Mike, based on the old Estes Intruder.
The difference is, Mike's INTRUDER boosts straight and actually glides - smooth, flat and LONG!
He's simplified the Estes design and lengthened the boom for a vertical boost.

Also launched:
The Dr. Zooch SATURN V with a Estes C6-5. Good high boost, lost a fin on recovery.
The Sun CONDOR Boost Glider pulled a 25 second glide with a Quest A6-4.
The Odd'l Rockets CYCLONE helicoptered for a good 20 seconds with an Estes 1/2A3-2t engine.
My GOBLIN Clone kicked with a C6-5 and long streamer recovery.
And finally, a new UP! CUP went unstable with a Estes C6-3. I don't know what happened, it''s been a reliable flier in both 13mm and 18mm versions. This is a new, slightly revised build, I'll double check it against the original before flying it again.