Striker AGM Launch Repairs

When you consider what a rocket goes through during boost, ejection and recovery you can expect some dings and cracks.
Sometimes I get away lucky - not this last launch.

If the rocket is valuable or a favorite, I spend more time fixing them. These two were quick fixes.

On the Striker AGM the rear of the fins didn't adhere well to the plastic boat tail reducer. Every flight one fin breaks away from the plastic.
The fin root edge was set back with medium CA. There was still chipped paint, the balsa showing through.
Without getting out the paint, Sharpie pens make for a quick touch up.



I usually weigh out if a major repair is warrented.
This is the second time a root edge has broken away when this model touched down.
Chances are, it'll happen again. It may not be worth the time for a major fix of gluing, filling, sanding, priming and paint.




At ejection you could hear the nose cone snap back and hit the body tube with a loud, hollow "thunk".
The nose cone was set back into the body tube to give a solid backing for the repair.



First, a white eraser was used to remove the dirt and paint smudge.

White glue was rubbed into the bends and creases on the damaged end of the tube.
A clean dowel was rolled over the bent areas working the glue into the tube.
TIP: Don't use yellow glue for an exposed repair like this. White glue dries clear, yellow glue dries yellow.

It's not perfect, but certainly stronger than it was after the flight.
In the last picture there was no paint used in the repair.

Enertek 2000 and Quest Striker AGM Comparison

Bob (Initiator 001 on TRF) posted this about an Enertek kit that was never produced.











Nice work on the Enertek Astra 2000 model. (See Picture)

Some history...
The Astra 2000 model was designed by Grant Boyd when he was working at Enertek. It was the 'first' Enertek model.

The prototype was made from parts of an FSI Black Brant kit.
By the time the Enertek catalog picture was taken, the model had sustained some damage. Thanks to lighting and selective photography, the damage is not seen.
Another Enertek kit makes it into production.

You can see the entire 1989 Enertek catalog HERE

Quest Striker AGM Fix

I wasn't happy with the stark white nozzle reducer on the Striker.
The model was painted an overall white and the white reducer stood out like a sore thumb.

I started outlining the areas between the fins with Testor's silver from a small bottle. A small pointed brush was used.

It went smoothly, the ribs on the plastic reducer would help hide any brush marks.
It wasn't difficult to paint the edges, the paint went on easily up to the masked paint line ridge and beneath that step between the body tube and reducer.

The small brush was cleaned off and I switched over to a 1/4" wide brush to fill in the middle.

I made sure to brush in the direction of the ribs. The ribs would hide any brush marks. The motor mount tube extending out the back was left white.
This is a much better finished look.

Quest Striker AGM Finished!

The Quest Striker AGM is finished. I ended up using a dull clear coat to give it a more military look.

It should be a great schoolyard or demo model with a B6-4.
It might make a good candidate for a D engine if the plastic tail cone/reducer could be reamed out and adapted.

Lessons learned:
The molded plates and raised detail on the Nike Smoke nose cone could be sanded down for a more generic conical nose cone. This nose cone is readily identified from the old Nike Smoke kit.
I should have spent more time on the plastic reducer. It could have been made out of cardstock to eliminate the step at the base of the main body tube. This would have reduced the masking problems.
Next time, go with the gray base color. While this scheme works okay, that white reducer sticks out like a sore thumb!
Still a sharp design with great looking split fins. The main body tube is STRONG! The decals were easy to apply and the clear edges almost invisible after a clear coat.

Quest Striker AGM Build Part 14 Decals Over Bad Mask

These are the "extra" leftover fin stripes.
There wasn't any need to apply black stripes over black fins.

Around the tailcone/reducer there was some mask lines that weren't very good. Here's a tip to clean them up.

TIP: Use sharp edged decals to clean up some bad masks.
Cut off the clear edges on one side of the long line decals.










On the left is the decal stripe over a mask that needed a rough edge cleaned up.
It hasn't been slid down yet.
On the right, the decal stripe is in position matching the black paint on both sides of the decal.
I simply covered up a glitch in the mask where the separation line wasn't clean.
I used more decal strips to clean up the lines around the tailcone/reducer.

After clear coating, you wouldn't be able to see the touch up decal unless you were really looking for it.

Quest Striker AGM Build Part 13 Ends and Edges

Lately I've been attaching the parachute down the shock cord, away from the nose cone to prevent tangles.

The Striker has the older Nike Smoke nose cone, it's a long one. Before tying on the parachute I made sure the nose cone tip wouldn't be hitting the upper body during recovery.





The kit decals were great! No problems at all putting them on.

The fin tip stripes are black. You can see the clear coat overhang beyond the leading and trailing edges of the fins.
Normally I would trim this with a single edge razor blade, but these decals stuck so well, I was able to roll the overhang over the fin edges.

Three of the lower fins are painted black. You are given black fin tip stripes to go over the black paint. If black decals were applied over black paint they would be invisible

I used these black stripes to a better advantage. See the next post -

Quest Striker AGM Build Part 12 Mask and Paint

This isn't going to be an easy mask.
There's uneven surfaces around the plastic reducer, a small step from the main body tube down to the ribbed tail cone.
I'm using clear Scotch tape again. Because the overall surface is white, the edges were hit with a wide point marker so I could see the actual line placement.



This shows the mask for the two red fins.
Cut up plastic grocery bags were used to cover the larger masked areas.






I can see now why Quest suggested the gray base color. The white reducer doesn't look quite right, it's a little stark next to he black and red fins.

Quest Striker AGM Part 11 Nose Cone Mask

There is a thin red band below the red nose cone tip.
This would be tough to mask so I took the easy way out using red electrical tape.

The tape was stuck on my window glass and cut with a straightedge. The red color match was very close.

On the rear, another thin black band goes above the black shoulder.
Again, I used black electrical tape.

In the Quest instructions, the suggested overall color is light gray.
I didn't have a can of gray paint. I never used gray paint on a rocket and couldn't justify buying another can of paint I'd never use again. So I went with the white, red and black decor.

Quest Striker AGM Build Part 10 Nose Cone Mask

Here's the arc cut Scotch tape mask applied around the nose cone around 2 1/2" from the tip.

Before removing it from the glass, I marked it with a permanent marker so it could be seen against the white nose cone.

The hardest part of this wrap is getting it on straight and the overlap when the ends meet.



The lower raised nose cone shoulder gets a black band.

The picture shows the nose cone tip after the top was sprayed red.
The red tip and middle have been masked. The black shoulder was then sprayed.

This lower black band was also masked with Scotch tape, but because the surface wasn't tapered, I didn't have to cut a curve. I used a 1/4" wide strip.




After removing the Scotch Tape, here's the red top of the nose cone.

Quest Striker AGM Build Part 9 Nose Cone Mask

The tip of the nose cone is painted red, the mask line is about 2 1/2" down.
I'll use the same masking technique from the Mini Orion nose cone.
At 2 1/2" down, the nose cone diameter is about 0.60".






This measurement was plugged into the transition tool at
http://www.payloadbay.com
The second wider measurement was .75". This measurement isn't that important but is needed to print out a arc for mask cutting.


This was template was taped to the outside of my glass patio door. You might call it a poor man's light table.

The door was shut leaving the template on the other side of the glass.
Clear Scotch tape was applyed over the smaller arc (to the right side) and cut down the black line.

This picture shows the tape already cut and stuck to the glass beside the template.

Cut the tape a little longer than the ends of the arc so you'll have an overlap when applying it to the nose cone.

Quest Striker AGM Build Part 8 Gluing Fins

Even after fitting the fins to the body tube and plastic adapter, there was still a small gap.

I've been using Titebond Molding and Trim Glue for fillets lately. It'll be interesting to see if this thicker glue fills the gap at the fin joint below the main body tube.

In the picture to the right, the fin at the bottom has a single fillet applied.
The Striker has four small forward fins, directly in line with the lower, larger fins.

TIP: I've clamped some longer tongue depressors (or Popsicle sticks) to the lower fins with clothespins.
Forward fins will slide right between the sticks giving perfect alignment with the lower main fins.

Above the forward fins is a wrap of paper. The root tip of the forward fin just touches the straight edge of the paper wrap. By using this wrap, all forward fin edges will be glued at the same height around the tube.

Quest Striker AGM Build Part 7 Filling Tips

On most models, I've been filling the balsa grain before gluing fins onto the body tube. This is for a few good reasons:
Trying to fill balsa (using sanding sealer or CWF) near a glue fillet at the root edge never gets good results.
It's easier to fill a flat fin surface when it's off the body tube.

TIP: You'll get a stronger root edge glue bond using the Carpenter's Wood Filler opposed to sanding sealer) if you choose to fill balsa fins before gluing to the body tube.
CWF is water based. Any white or yellow glue adheres better to a water based filler. Sanding Sealer or Balsa Fillercoat will seal the wood and not allow glue into the wood surface when adding fillets. Some builders still prefer sealer and fillercoat to fill balsa.

Look at the lower half of the Striker fin root edge.
The flat balsa surface (facing away) has one dried coat of CWF.

Look close and you'll see the curved warp down the root edge.
The side of the fin you can see has yet to be painted with CWF.
When the second side dries, the new filler will straighten out the curve.

Contrary to what I've read on the rocket forums, most thin balsa will warp using a sanding sealer or CWF. I've used sanding sealer off and on since 1969 and it pulls and warps as it dries. I was told by an experienced model plane builder that dope finishes will keep curing and tightening for years. (I don't know it that is true or not.)
When you fill the other side the bend should go away without laying waxed paper and weights on it while drying.

Again off the model, the launch lug gets the seams filled with CWF.

When filling body tube seams, CWF can crack and pop out when sanding. I tend to use one application of CWF on tube seams, then rely on sanded primer to fill any remaining lines.
I wish body tubes would hold CWF as well as launch lugs do. (See the next post!)
One coat of CWF and sanding and lug seams are filled! The CWF locks onto the launch lug seams and won't crack or fall out when sanding.

Quest Striker AGM Build Part 6 Launch Lug and Standoff

Jumping ahead to Step 9:
I don't know why this lug standoff wasn't included on the laser cut sheet. Not a problem, there is plenty of extra balsa left over.

Here I've extended the lines on the standoff template. I can cut out the standoff by setting the balsa over the plan. This way I'm not cutting up the instruction sheet.



The supplied lug is the correct length of the top side of the standoff.

Quest Striker AGM Build Part 5 Fin Fitting

When the motor mount assembly and plastic reducer was slid into the main tube, I found one side of the shoulder lip to be wide.

In the picture, the left side of the shoulder is a good fit, the right side has a noticeable step.





I taped the reducer in place and pencil marked fin positions 1 - 4.

Because the shoulder lip was narrower on one side, each root edge fit was going to be different. The fins have three angles on the root edge. Each fin would be individually fitted!

Fin 1, on the wide side, fit well when removed from the balsa sheet.
Fins 2 and 3 (opposite each other) took a bit of sanding and ended up with the same root edge shape.
The Fin 4 root edge took more shaping and had a "step" at the body tube and reducer joint contact point.

Quest Striker AGM Build Part 4 Fin Fitting

The laser cut balsa fins were of a good quality.
They were removed from the sheet without problems.

I stacked and sanded the edges, removing almost all of the burnt edges.
I didn't sand the root edges - yet.

The first picture shows the dry fit of the root edge against the tail cone reducer.



I wanted a better fit so some careful sanding followed with my sanding block with 220 grit sandpaper.

You can see where the balsa was removed by how much of the laser burn (dark brown) is left on the root edge. It doesn't take much sanding to get a better fit.



Here's the improved fit after trim sanding.

This fit won't be perfect because of the step between the adapter and the body tube joint.
Still, it now has a better gluing area with more contact with the three different surfaces.

Quest Striker AGM Build Part 3 Nose Cone

I jumped ahead to the nose cone.
Before gluing, sand off the molding flash especially on the side without the alignment pins.
I've had some experience with the old Nike Smoke two-piece cone before.


To see one way to fill the seams and molding dimples,
Check last year's Nike Smoke post HERE

After the two sides were glued together, medium thickness CA glue drops were set into any concave seams and dimples.

After it thoroughly dries, the rasied CA is sanded to the surface of the cone.

Quest Striker AGM Build Part 2 Engine Mount Adapter

Step 1 is a typical engine hook install.
Slit the tube 1/4" from one end. Insert the hook and wrap with tape in the middle.
I substituted a 2 3/4" length of BT-20 for the thin Quest yellow tube.

Check the first photo. The interior ribs extend past the top and bottom of the adapter a little bit. Sand the top and bottom flat so you'll have a better flat gluing surface for the centering rings.



After the rings were glued in place, the adapter assembly wouldn't slide into the 35mm tube easily. Sand the ring edges to the diameter of the upper and lower adapter ends.




The smaller, lower ring will be exposed.
The brown ring is a little rough. I hardened and sealed it for smooth sanding by applying a coat of CA brushed on with a Q-Tip. A little sanding with 400 grit will leave a smooth surface for paint later on.

There is an "gotcha" in step 3. With a wrap of tape around the engine tube and over the hook, the tube won't slide into or past the upper centering ring.
I removed some tape and widened the inside ring diameters for a better fit.
I'd recommend cutting a notch for the hook, especially on the lower ring. Otherwise, there wouldn't be enough hook movement to allow an engine to be inserted.

Quest Striker AGM Build Part 1 Parts

Here's all the parts, right out of the bag.
The Striker AGM looks to be a great design, perfect for demos and small fields with a B6-4.
The 35mm tube is long, just a little over 18" long.
The blue engine block isn't shown, it was found inside the yellow engine tube after the picture was taken.

The pieces of interest:
The engine hook will be replaced with a spring steel hook made from the metal strip inside an old windshield wiper blade. This hook included with the kit bends easily. Looking ahead at the engine mount, the hook will need to be flexible.

The yellow engine mount tube is a little thin. It has a rough finish and would require a smooth surface where it's exposed out the back of the tail cone. I'll substitute a BT-20 tube.

The centering rings seem thin, but should be fine the way they are assembled in the mount.

The tail cone has ridges on it. There is four recessed lines used for fin alignment.
The thickness of the ridge around the shoulder is inconsistent, thinner on one side. This might effect the fin root edges contacting the body tube.