Thursday, July 12, 2018

BAR Fleet #113 - Lunar Patrol 3

Yup, Folks, Here it is....
21 blog posts and nearly a year and a half in the making....



Model Info and Specs

Lunar Patrol 3
Based on the Model Products Corp. Lunar Patrol, Kit # R-215
Original Kit Produced:  1969- 1978
Designed by:  Fred Nardei

Completion Date:  12 July, 2018

Booster Rocket

Length:  42cm
Diameter:  19mm
Weight:  20.1g
Single Stage
Motor Type:  18mm
Parachute Recovery
Color Scheme:  White, Silver, Red, with multi-color markings.

Gliders

Type:  Delta Wing
Lengths:  18.5cm
Diameters:  19mm
Weight:  (Avg.):  10.75g
Color Scheme:  White, Red, Black

Overall Vehicle

Length:  58.3cm
Weight Empty:  41.6g

About The Lunar Patrol 3...

Back in the ‘old fleet’ days, my all-time favorite model rocket to fly was an original MPC Lunar Patrol, followed by a custom designed re-build version of the booster rocket.  The sight of the model streaking straight upward, then separating into three sections at ejection, was fun to watch.  The booster would descend under its parachute while the gliders wheeled about on their own separate flight paths.  The bird was always a crowd-pleaser at club demonstration launches.

As a Born Again Rocketeer, a clone build of the Lunar Patrol was an absolute necessity!  Scanned plans of the original MPC kit instructions and templates were download from the Ye Olde Rocket Plans website.
This build cannot be considered as a true clone of the original kit because I went with Estes BT-20 tubing for the main airframe and glider fuselages.  The original kit had slightly larger diameter body tubes.
Also a currently available Estes PNC-20-something nose was used.                                              

Another deviation from the original Lunar Patrol revolves around the motor clip.   The MPC kit utilized a standard clip that was attached to the outside of the main body tube and held in place with a larger diameter tube that slid over it.  My re-build uses an internal motor hook made from .020 music wire.
 
In addition, since the published plans did not have really clear illustrations or dimensions for the glider noses, I estimated the sizes and turned them on the wood lathe.

I am quite happy to have another Lunar Patrol in my current fleet, and look forward to many flights  with this interesting bird.


Wednesday, July 11, 2018

MPC Lunar Patrol, Part 20 - Glide Trimming

The final process of the Lunar Patrol build is to trim the gliders for flight.
The noses have been left unglued to the body tubes to facilitate this.
For trim weight, I am going with a #6 x 1/2" sheet metal screw and the required number of stacked #6 washers to be attached to the base of the balsa noses.


A quick trip to a local grass-field park, and I'm ready to try it out.
The noses have been inserted so that the attachment pin is oriented to the top of the glider.  I expect several hard landings during trim testing, and I don't want to break them off.


Small delta-wing gliders are notorious for being somewhat difficult to trim out.  I found that giving the birds a good heave in a near vertical trajectory gave them enough altitude to do whatever looping and turning was necessary before they would settle out into a glide pattern.
With five washers installed per bird, I was pleased to observe that they would properly flatten out into a good glide with a very minimal stall pattern.



I did note that they were highly susceptible to even the slightest wind disturbance, but would recover quickly.
Satisfied that the trim of both gliders was well within the desired window, it's off to the work bench to permanently glue the nose cones in place (remembering, of course, to put the attachment pins in the correct orientation!).
Hear are the completed gliders, all ready for their maiden powered flight. 


Any further tweaking of the glide trim will have to be done while observing a real flight, with  judicious placement of additional trim clay.
Also, the hand launch trim testing did not reveal much information about the extent to which the gliders turn, since they did not level out into glide until they were a few feet above the ground.
From my initial observations, they seemed to fly fairly straight.  Again, a powered test flight will reveal if I need to trim for a slight turn.  I don't want to be chasing two gliders into another county (or two different counties 180 degrees apart!).
Anyway, I do believe the Lunar Patrol is officially finished!


Tuesday, July 10, 2018

Hobby Lobby Finally Comes To Castle Rock, Colorado

For the past several months, my morning and afternoon commutes to and from work have taken me past a building under construction only a mile and a half from my home. 
A sign next to the building touted: "Coming Soon - Hobby Lobby".
Everyday, as I drove past, I glanced over to see how construction was progressing, greatly anticipating finally having a small source of model rocketry supplies in my neck of the woods.
The store finally opened a couple of weeks ago, and I paid my first visit this past Saturday.
Hanging on the rocketry wall was the usual fare of Estes product carried by all Hobby Lobby stores.
I am elated that I have this so close to home now.  Previously, I had to travel to Lone Tree (South Denver), a 20 mile drive from Castle Rock, to get to the nearest Hobby Lobby.
Time to start printing out them 40% off coupons......


Monday, July 9, 2018

MPC Lunar Patrol, Part 19 - A Near Disaster!

In the two years since I became a BAR, every single rocket that has been added to the BlastFromThePast fleet has had some kind of small imperfection or problem.  I try to be as careful as I can during building and finishing, yet I always find that one small paint blemish, or one spot of balsa grain that didn't get quite filled, or a slightly mis-aligned decal, or some other issue. Although it doesn't distract significantly from the overall model, it's still there.
And it irks me!
This weekend, I made a huge error that almost caused me to have to trash one of the Lunar Patrol gliders.
And it occurred on the very last build/finish operation.
Last Friday evening, I mounted each of the gliders on a building spike consisting of motor casings glued to a piece of cardboard.  This was so I could apply a light coat of Future to the glider top-sides to seal the decals.
Saturday afternoon I went to remove the gliders from the spikes.  One slid off easily...the other one was stuck fast to the motor casing.  Apparently, some of the Future had seeped in between the body tube and casing, virtually gluing the two pieces together.
No problem, I thought...I can just twist it off.   No deal.  It wouldn't budge. 
And in the process of trying, the upper motor casing broke off from the rest of the spike.
To my chagrin, only 1/16th inch of the casing remained protruding from the glider. Not enough to grab on to with any type of pliers.
Now what?  I found a length of dowel and tried pushing the casing out from the other end.   Fail!  That thing was stuck fast.
Next I tried drilling out the ceramic nozzle large enough to fit a sturdy hook inside the casing and attempt to pull it out.
That didn't fly, either.
I realized that any further attempts to remove the casing using any of these methods would likely result in breaking wings and fins off the glider, severely damaging the body tube, or both.
I put the model down on the bench and walked away, resolving to brainstorm another way to solve this sticky problem.
That night, while in bed around 2 a.m., I popped wide awake and thought about that glider. I envisioned a solution that just might work!
The next morning, I hustled down to the basement shop, found a short piece of scrap BT-20 tube, one of my painting wands consisting of a motor casing glued to the end of a dowel, and one of my woodworking mallets.
Before attempting the operation I had planned, I ran an X-acto knife blade around the joint between the glider tube and stuck motor casing to break the surface seal.
I placed the body tube section over the tiny bit of exposed motor casing and butted it up against the glider tube. 
Standing the assembly vertically on the work bench, I slid the painting wand down the front of the glider tube until it contacted the stuck motor casing inside.
One sharp rap with the mallet on the end of the painting wand dowel was enough to break the motor casing free!
Phew!  Now I didn't have to trash anything and set back the Lunar Patrol completion date based on the time it would take to build and finish a new glider.
As for damage control, there were only some very tiny dings at the very end of the glider tube.  A little sanding and paint touch up was all that was required to make things good again.

Here is a pic of the glider, the kit of 'extraction' tools, and the offending motor casing.


A little bit of Yankee Ingenuity to correct a stupid Yankee Mistake!

Friday, July 6, 2018

Phew! Back In Business In Castle Rock!

I just received an e-mail from the Fire Prevention Officer at Castle Rock Fire & Rescue.
After researching the Municipal Ordinances and Regulations, he found that model rockets are permissible if there are no Stage 1 or 2 Fire Restrictions in effect.
Yippee!!

Thursday, July 5, 2018

Drat!...Lost My Castle Rock Launch Site

I just learned that the Town of Castle Rock, Colorado had recently re-drafted their Municipal Ordinance.  One of the changes specifically prohibits the launch of model rockets within city limits.
This means I lost the use of that really nice B-engine field adjacent to the high school, that is a mere half-mile from my house.
Bummer!
Oh, well, I can at least still use the field to hand launch all of my gliders for glide trimming....

An amendment to this post... Maybe all is not lost. I contacted the Castle Rock fire department, and received an email which spells out model rockets not being permissible during stage 1 or higher fire danger, which the area is under right now. I sent an email response asking if rockets are permissible at times there are no restrictions in place.  Still awaiting a reply.

MPC Lunar Patrol, Part 18 - The Final Decals

This morning, I was up at 4 a.m. merrily affixing the final decal to one of the gliders.  This is a remake of the same decal I hopelessly muffed up on a week ago, and had to discard.  This time things went very smoothly.


I also managed to apply some CA to the end of the booster tube, and get the shock cord and mount glued in place.
All that remains on this build is to apply some sealant over the decals, shoot a finish coat of black paint on the glider noses, take the gliders out to a nearby field for hand-toss glide trimming, and glue the noses in place. 
It's been  a long drawn out build, but I greatly anticipate seeing this model finally take to the air under rocket power!