Mercury Little Joe I [Archive] - The Rocketry Forum

MaxQ

30th May 2009, 11:16 PM

The capsule/cone will be a replica of an early boiler plate Mercury capsule and will have a lot of vertical ribbing on the exterior.
The tough part will be rolling a good transition shroud for the capsule to mate to the airframe.
Again, I'm using a motor mount tube as the load bearing part internally.
The exterior of this thing needs to have a precisely radial cut shroud that will wrap around.

And it will need to match the capsule base and body tube dimensions precisely.
The dimension change of the transition on this version of the rocket is very subtle.

Given the foam board building materials, this will need some trial and error adjustment, these aren''t exactly high tech materials.

Again, I'm not "engineering" this thing like other fine builds here, this is a "low cost", "quick and dirty" build for amateurs like me.

I ran several calculations on the transition/shroud using online tools.

After several failures when trial fitting the results to the capsule and airframe, I tossed them and made an oversized copy on mylar sheet...
I wrapped the new mylar version around the transition base parts and then made trim marks to cut the thing down.
Sometimes you just got to say "Sxxxx It", and use the best measuring device, a trained eyeball......
This gave me something I could use....FINALLY.

MaxQ

30th May 2009, 11:26 PM

trial fit....so far, looks ok.

MaxQ

30th May 2009, 11:34 PM

Once I got the capsule foam core "floor board" trimmed "in-round" as accurately as I could, and the transtion properly sized...I cut a chrome skin for the transition/shroud too.
Spray mount carefully to avoid overspray of the nasty stuff on that fine chrome finish, and applied to the posterboard shroud.

MaxQ

30th May 2009, 11:41 PM

Assembling airframe components is next.

Need to take some more pictures....

MaxQ

30th May 2009, 11:43 PM

The transition works.

And the exterior finish of this airframe and transition looks real nice....
If I can keep it clean during the build, I won't have to worry about priming and painting a decent silver/aluminum finish.

MaxQ

31st May 2009, 12:10 AM

The next "build items" will include :

- escape tower
- escape rocket motor and nozzles
- internal thru the wall fin structure and fin skins
- cluster motor mount assembly and recovery harness points
- capsule exterior details

See 'ya later

MaxQ

2nd June 2009, 05:10 AM

The capsule will need the forward nose cone section, the little conical cap on the front that attaches to the inside of the escape tower, and the reinforced ribs that are around the capsule exterior.

I turned the little cone with a sheet of mylar. I'll fiberglass that after test fitting and trimming.

Plastic strip was cut and cemented to the capsule exterior wall with liquid cement.

MaxQ

2nd June 2009, 05:18 AM

The tower will be made from wooden dowels of various sizes..they are a little larger in diameter than the actual "true scale" dimensions indicated, - but the dowel selection was limited...and I figured erring on the side of a slightly larger size couldn't hurt for strength...

I made a jig for the tower after dimensioning the three vertical parts from a scale plastic scale model kit.
Taking critical dimensions from a kit and transferring them sure makes this build go much quicker than figuring out the assembly from a few photos and elevations....

I sketched the triangular cross section and the base ring for the tower, and took a dimension midway inside the tower and set up the dowels and started tack gluing it together.
The diagonal braces were then cut and glued in while the tower was on the jig.

MaxQ

2nd June 2009, 05:24 AM

The best part of a "scratchbuild" is when you pause, and take a look at the assembled pieces...around the time it starts to look like something.

Pantherjon

2nd June 2009, 06:44 AM

Looks awesome! :)

JoeG

2nd June 2009, 01:06 PM

Looks great! Lots of good info too.

Any time I try to build a tower it seems to lean a little.

Micromeister

2nd June 2009, 02:11 PM

That's some beautiful work MaxQ. Great job.

MaxQ

3rd June 2009, 02:03 AM

Thanks Guys!

Can't wait to see how this will look with paint on it...some flourescent Orange on chrome will be cool.

MaxQ

3rd June 2009, 02:07 AM

Looks great! Lots of good info too.

Any time I try to build a tower it seems to lean a little.

Towers, yeah.
This one has a slight lean as well, which I will deal with.

Wood dowels have warps...I went thru two dozen at the LHS and pulled four that were fairly straight.
But uneven ends and a slight bevel on a cut will result in a lean...

I have a ring I am making for the base of the tower which I'll need to apply shims under one side and true it up.

I am on "hold" for a collection of 24mm, 29mm and 38mm MMT's...but I'll be trying to keep the build thread going...

I will probably have four 24mm's, four 29mm's and a central 38mm.
I know the central 38mm is not true to scale...there was no central motor on the full size Little Joe I.

But my philosophy on clusters, and particularly airstarts, and mixing BP with composites, is to have a central motor that will fly the rocket by itself (if the outboards don't light) and all the outborads for fun, when they do.

I'll be putting a timer behind a hatch with a pull pin...this to deal with problems I experienced with airstarts on my Apollo Little Joe II.

billspad

3rd June 2009, 12:11 PM

Towers, yeah.
This one has a slight lean as well, which I will deal with.

Mercury towers had a little bit of a lean to them so the tower would move away from the flight path of the capsule when it was jettisoned.

bsexton

3rd June 2009, 12:57 PM

What is it with you and "Joe" rockets? :D

Seriously, looks like another great project and once again you are proving bigger rockets don't have to be heavy rockets.

Meatball 1

3rd June 2009, 01:58 PM

Lookin' good once again, Jim.

MaxQ

4th June 2009, 12:29 AM

What is it with you and "Joe" rockets? :D

Seriously, looks like another great project and once again you are proving bigger rockets don't have to be heavy rockets.

Well, the light weight makes it more affordable to fly.
Smaller motors...slower takeoff speed.

And a slow moving "scale model" rocket just, looks more realistic.
To me anyway.

After this "Joe" I may not know what to do...I've run out of "Joes"....

MaxQ

4th June 2009, 01:25 AM

Mercury towers had a little bit of a lean to them so the tower would move away from the flight path of the capsule when it was jettisoned.

Maybe I should leave the lean - in, then?

Any idea how much deviation from true 90 degree vertical we're talking?

(Or are you jivin me?)

GuyNoir

4th June 2009, 01:56 AM

Or are you jivin me?)

I suspect Bill doesn't know how to jive.. . .:roll:

billspad

4th June 2009, 03:36 AM

Maybe I should leave the lean - in, then?

Any idea how much deviation from true 90 degree vertical we're talking?

(Or are you jivin me?)

I do know how to jive but I'm not.

I've got a bunch of drawings and a file cabinet draw full of Mercury Little Joe stuff. I started collecting it so I could build one and ended up with so much detail that I've never had the time to do it right. Ten years ago I took a drawing I got from NASA and had it scanned and converted to a vector drawing so I could clean it up in AutoCad. While doing that I "fixed" the tower to make it straight. I later learned that was a mistake. I can't remember the number but it's small. On some of the earlier flights they just shimmed where the motor attached to the tower enough so the centerline of the thrust was offset an inch where it passed through the center of gravity.

I think I attached a .pdf of the cleaned up drawing.

Here's a trivia question for you. There are a couple Marman clamps on the capsule and tower. The biggest one holds the capsule to the booster. Who invented the Marman clamp? Googling is not allowed.

rocketguy101

4th June 2009, 03:55 AM

After this "Joe" I may not know what to do...

Little Joe III (http://www.orbital.com/HumanSpaceExplorationSystems/HumanSpaceSystems/OrionATB/) ? :D Not quite as interesting...

g_boxwood

4th June 2009, 07:41 AM

Max, that's a cool project and I do agree with you about the finish: the chrome/bright orange pattern will simply look amazing!

Nice work on the capsule detailing, prior to commit myself to the Apollo LES I wondered wether to model a Mercury or an Apollo capsule, maybe the Merc will be next!

Keep it coming!

MaxQ

4th June 2009, 01:48 PM

Here's a trivia question for you. There are a couple Marman clamps on the capsule and tower. The biggest one holds the capsule to the booster. Who invented the Marman clamp? Googling is not allowed.

Mr. Marman?

Dunno...but whoever did made their marx in the history of industrial design.

MaxQ

4th June 2009, 01:50 PM

billspad

4th June 2009, 04:51 PM

Mr. Marman?

Dunno...but whoever did made their marx in the history of indstrial design.

Did you peek or did you know?

MaxQ

4th June 2009, 05:41 PM

Did you peek or did you know?

I had absolutely NO knowledge of anything.......

MaxQ

6th June 2009, 02:52 PM

Did a little more work on this component.

I found an Estes body tube for the escape rocket that was almost dead on for width.

The escape rocket will need a base for the motor nozzles which I will carve out of sheet plastic.
This will use a standard centering ring on one side to plug in the body tube.
The other side will need some work to make attachment points for the angled nozzles.

Nozzles are to be cone/shrouds turned in myler, which will be fiberglassed over.

MaxQ

6th June 2009, 02:55 PM

Here are the roughed out parts for the bottom of the escape tower.

MaxQ

6th June 2009, 02:57 PM

After some trial fitting and sanding...making sure the plastic part will center on the body tube and the tower will mate to the hard points on the nozzle base.

MaxQ

6th June 2009, 02:59 PM

Next are the nozzles, and the escape rocket base which is a bit simplified.
I'll probably look for plastic nuts and bolts to enhance the design and appearance when I have time...the attachments for each motor nozzle need to be angled...

The tower base ring is on the left in the picture.
Cut from plastic sheet...and trimmed and shaped.

MaxQ

6th June 2009, 03:03 PM

Next, trial fit of the nozzles on the rocket body base, check for clearance of the nozzles thru the tower legs..

MaxQ

6th June 2009, 03:11 PM

...and then a trial fit of the tower assembly for correct mate to the detailed base with the nozzle attach points.
The tower legs will have to hold the escape rocket securely throughout the flight and recovery,....thinking of screws and reinforcement with small washers in several locations maybe...?

MaxQ

6th June 2009, 03:13 PM

...and a check on all the various components together.
Escape rocket itself will need a nose cap and exterior detail bands and various other things, and of course the aerospike doo-dads on the top.

There is a tower base ring in this picture that I made out of laminated rings cut from sheet plastic, which is sized to fit around the mercury capsule nose cone.
This will be an important part...needs to be leveled and securely attached - it is a load bearing part that holds the tower to the capsule.

Tower legs will need epxoy reinforcements on the strut attachment/weld points...and there is a lot of wiring and other little details to do.

The body tube and/or nose cap will be removeable to add lead weight for CG adjustment for different cluster motor configurations...

MaxQ

8th June 2009, 03:24 AM

Did some work on the escape rocket motor details...
The base received a row of aftermarket hex bolts, purely for appearance.

MaxQ

8th June 2009, 03:26 AM

My camera doesn't take very good closeups but I tried here...

The escape rocket also got some detailing with bands which will have clamps...there are other things like wire tunnels and other fittings.
The wire tunnels are angular and I used triangle balsa stock for those.
Bands are cut from the excess body tube...
The big block of balsa on the end is to carve and shape a nose cap.

Again, I copied dimensions and other details off the plastic model kit.

MaxQ

8th June 2009, 03:31 AM

Since there will be a need to add lead ballast for CG adjustment later, I'm making the escape tower nose cap removeable.
The nose cap with cardboard triangular fittings slides over the triangular wire tunnels on the escape rocket motor tube.

MaxQ

8th June 2009, 03:33 AM

Trial fitting again...this was before the nose cap was shaped.

MaxQ

8th June 2009, 04:05 AM

Here are the components to date, unglued for a trial fit.

Capsule will get a trim ring around the base.
There a numerous bolts and bolt recesses around the transition rim to do.

When I get the four 24mm/29mm and central 38mm motor mount tubes I can begin the cluster motor mounts and centering rings.
The eight motor tubes will be angled/vectored like the real deal.
Looking for nozzles for them too.

The fins will need to work with those motor tubes as they are thru the wall fins...to mount to the motor tubes inside.

g_boxwood

8th June 2009, 12:01 PM

Wow, superb detailing!

Keep it coming!

MaxQ

10th June 2009, 11:34 PM

Wow, superb detailing!

Keep it coming!

Grazie!

More to come when I get motor tubes and fin material.
I will be taking a break while I wait for parts....so,

Arrivederci

MaxQ

18th June 2009, 01:24 AM

I was able to get motor tubes over the weekend (thanks Bruce!).

After establishing the dimensions and cant angles for the tubes on paper, I set about drawing up centering rings to cut out of foam core and then marking the holes for cutting to receive the cluster motor mount tubes.
Yes..foam core.
Don't worry, this flimsy stuff - while easy to cut w/o a shop or fancy tools is going to be reinforced as I did with the Apollo Little "Big" Joe II project, which used the same material and survived.
(I think of it as a "model rocket" ......on steriods).

The outer ring of four 24MMs coincides with the four fin root locations, and have pronounced cant angles, just like the full scale Mercury Little Joe.

The other four 29MMs - I fit as best I could.
The central 38MM is non scale, but I like a central motor that is capaable of lifting the whole rocket by itself for first flights, and in the event other outer motors don't light...on later cluster flights.

MaxQ

18th June 2009, 01:30 AM

The upper centering ring gets holes for the tops of the motor tubes that are each closer together, due to the cant angle of all these tubes.
It is a little "out of round" as I couldn't find a blade holder for my beam compass...I'll have to trim it after glassing.

The remaining foam core between the holes on this upper centering ring starts getting pretty weak after all the cutting....so reinforcing the centering rings with wood sheet, fiberglass cloth and spruce wood strip bracing is in order.

MaxQ

18th June 2009, 01:39 AM

Trial fitting of the phenolic motor tubes..to check cant angle and to checlk for fin clearance.

The assembly starts getting much stronger when assembled and epoxied together.
The entire motor mount assembly when inserted into the ariframe will get buttressing inside the airframe wall, holding down the top centering ring.

The weight does start to rise noticeably too.

I don't have a target weight yet, but if it turns out anything like the Apollo Little Joe II, it won't be much...

On the other hand, I won't be clustering J or K motors in this thing either.

MaxQ

18th June 2009, 01:42 AM

The "business end" as they say....

MaxQ

18th June 2009, 01:53 AM

Hoping that it will look something like this.......with the right motor combination.
ok ok....unlikely, but even if only half as good as this - it would be pretty cool.

bsexton

18th June 2009, 01:35 PM

Keep up the great work - can't wait to see this baby fly!

georgegassaway

20th June 2009, 04:25 PM

FWIW - below is a photo of a crude boilerplate for a 1/22 scale (7” diameter) Little Joe-II. This test was with a G25 and six C6’s. So, you can see how the exhausts interacted.

The real model had a capability to use six 24mm engines (plus center 29mm), but it never flew on more than a G25 and six C6’s before it crashed. It crashed because one day the six C6’s lit but the G25 did not, so it went up 100 feet then came down 100 feet, and smashed.

So, be really careful you get the center motor lit if that is the only one that deploys the recovery system. I had thought of adding R/C ejection to it, and if I had, it would likely have saved that model. If I do something like that again, I probably will add R/C ejection to it.

- George Gassaway

MaxQ

20th June 2009, 10:23 PM

George:

thanks for the tip (sorry to hear that nice Apollo LJ-II went in).
Point well taken.

I thought over the motor set up...and despite the fact the central 38 MMT is non scale, my feeling is get a central motor that can do the lifting chore, and recovery ejection chore - even if it is non scale. I feel a little better not having a motor set up that is a completely "scale like" cluster ( - with no central motor) since I won't have to worry as much about off center thrusts if some of the out board cluster motors don't light.

If I master the composite cluster motor ignition techniques, I can always put a scale looking cover plate over the central motor hole and go for it.

On that problem you mentioned...I have this set up to have ejection into the main parachute compartment from all motor tubes...but in order to get adequate altitude for safe deployment it is still imperative that central motor lights. (the first flight of my Apollo LJ-II was a real gut check..the main parachute got line stretch off of a single G motor but only just in time....then the outboards lit off a GWiz as it touched down under canopy ...a whole other story...but it demonstrated the risky potential of a flight on a single G motor).

Food for thought....short delays for first flights...just in case the altitude ends up lower than expected....(the Apollo Little Joe - II project I made did very nicely on a single central H-97 with a short delay. Chutes out - right at apogee).

Delay choices will need to be thought over carefully as well, and by all means, a good cluster ignition system when the time comes.

And when mixing composites and BP motors , I'll need to take extra precautions.

Your experience with the central motor on the LJ-II failing to light gives one pause to think...

While I have a central motor set up to deploy the recovery system, and the outer MMTs can also pass an ejection charge thru ...BUT, therein lies the potential dilema(s):

I'll likely do some flying w/o motors installed in all the outer tubes for at least several early flights...and I'll need to remember to plug the empty outboard tubes - the ones that have no motor installed - lest the empty motor tubes allow the ejection charge out the back through the empty motor locations.....and weaken the main recovery ejection.

Checklists. I'll need checklists.

Also, the combined pressure of an ejection charge from all motors gooing off at the same time....IF the BP motor ejections happen to go off at the same time as the composite motors, - needs some thought......

MaxQ

24th June 2009, 04:31 AM

Here is the fin can motor mount assembly, with the centering ring wood strip reinforcements

MaxQ

24th June 2009, 04:36 AM

For strength...a "through the wall" fin attachment arrangement was what I wanted, unfortunately, as on the full scale Little Joe, the four outboard motor tubes align with the four fins...so through the wall fin attachments will have to be to the four outboard/canted 24mm motor tubes, instead of the central 38mm tube.
Made for a bit of a design problem that I had to deal with.

I elected to go ahead and keep the scale fin and motor locations - the fin roots will attach to the 24mm motor tubes....
Not the best solution....best I could come up with.

So, I plan on bracing the 24mm motor tubes inside between the central 38mm motor tube and along the inside wall of the four 24mm...and reinforcing the 24mm motor tube walls.....

Ply fin braces were cut , with ply fin roots to support the fin framing.

MaxQ

24th June 2009, 04:42 AM

The fins were framed up, and four sets made, built upon the ply fin roots that will go through the airframe wall and each attach to the canted four
outboard motor tubes.

Fins will be skinned with either 1/64 ply or maybe posterboard skins...

Careful dimensioning required and test fitting...the fins roots will have to seat on each motor tube - inside the airframe.

MaxQ

24th June 2009, 04:47 AM

Here is a test fit of one fin to the fin can...w/o the internal bracing between the central 38mm and the 24mm tube installed as yet.

The fin can motor tube assembly will be epoxied into the airfames and then the fins inserted.

So far, it all lines up. Assembly should be trouble free.

MaxQ

24th August 2009, 02:28 AM

I got around to getting the cluster motor mounts inserted and epoxied in.
Fin slots were cut, and fins inserted thru the wall to seat the fin roots on to the four canted, reinforced outboard motor tubes.

That done, the fins were epoxied on, with care. The exterior finish on the airframe had to be protected.

MaxQ

24th August 2009, 02:31 AM

The internal centering ring will get buttressed with angled pieces to handle launch stresses...also need to attach a recovery harness hard point to the central motor tube (similar to the Apollo Little Joe - II project, which has held up well for five flights).

I'll be laying vertical wood strips on the inside wall to help reinfoce the airframe...

MaxQ

24th August 2009, 02:32 AM

Here's how it sits..

MaxQ

24th August 2009, 02:34 AM

Here is a shot with the new fins and some of the components test fitted...
Next...back to the escape tower.

Need to devise some hardware to secure the tower base ring, and continue detailing the capsule.

Pantherjon

24th August 2009, 04:16 AM

That is coming alone very nicely! Love the chrome 'skin'!:D

Pem Tech

25th August 2009, 10:49 PM

Did you peek or did you know?

That was Harpo's father was it not?

billspad

25th August 2009, 11:20 PM

That was Harpo's father was it not?

No it was Zeppo, the youngest brother.

Pem Tech

26th August 2009, 12:07 AM

No it was Zeppo, the yountest brother.

DOH!
Thought I had that one nailed.

MaxQ

4th September 2009, 03:36 AM

Yeah....
Got tired of reading the Doh!...so I thought I'd just post this.
Working on details ...no pictures of them yet.

MaxQ

17th September 2009, 05:10 AM

Worked on the escape tower mounting ring...took my dremel and drilled several holes at an angle thru the bottom of the ring into the dowels.Touchy operation but it worked....kinda.
(notice the split in one tower leg in the picture/lower right from the screw. Small setback...will need to be wrapped and sealed).

Mounting screws should hold the tower legs to the ring, which will attach to the capsule..with more hardware
The tower rocket will hold lead ballast so this will need to be a firm attachment .

MaxQ

17th September 2009, 05:14 AM

The escape tower rocket motor nozzles are small cones that were turned out of folded mylar sheet. Each nozzle got a layer of fiberglass cloth and then some filler.

MaxQ

17th September 2009, 05:17 AM

The escape rocket motor was sanded and got a coat of primer.
Trial fitted the nozzles for clearance past the tower structure...
Will need to drill more holes in the tops of the tower legs to hold the escape rocket motor to the tower leg dowels, and washers on the tabs of the motor base for small screws.
Hope to pick up the pace a bit after the finicky work is done.

bsexton

17th September 2009, 12:30 PM

Are you going to have this thing ready for the Fall Battle Park Launch?

MaxQ

17th September 2009, 01:36 PM

Are you going to have this thing ready for the Fall Battle Park Launch?

Hoping to , yes.
Shouldn't be too difficult if I get a couple of free weekends between now and then.

U812

19th September 2009, 07:06 AM

This is just such good work. I applaud you!

Steve

MaxQ

19th September 2009, 05:44 PM

Thanks U812 - like to see some of your work..visual effects...

While I'm doing the detail work and butressing the inside of the airframe, I was considering how to go about doing outboard motor ignition on future cluster flights.

The central composite motor makes lighting outboard 24mm BP motors a little tricky in the timing dept.

Flash pan techniques have worked on rockets with a central composite motor w/ BP outboads, but I don't want to fry the exterior detail on the bottom of this model so that's out.

The "spider" technique is cool but I have such a radical cant on some of these outborads motors that I think that one is out.

The Apollo Little Joe II on filght #5 finally got the right amount of "umph" on lift off with an H123 to trigger the G switch on my GWiz flight computer to light the outboards...So, if I cut a hatch and build a bay for the GWiz that would work.

I'll need to retro fit a wiring conduit to the motor base plate.

However, ...
On this model I would like to use a smaller central composite motor, which puts me back in the situation of not enough umph to trigger a G switch.

Anybody have experience with a reliable pull pin timer I could use and keep this cluster ignition sequence really simple?

U812

19th September 2009, 06:45 PM

Just go to my web site there's some there.

Can't wait to see this fly.

Steve

MaxQ

20th September 2009, 02:30 AM

Just go to my web site there's some there.

Can't wait to see this fly.

Steve

Interesting stuff there on your website.

<Can't wait to see this fly.>
That makes two of us.

U812

20th September 2009, 02:40 AM

Max thanks. Well I'm focused now. I'm back to the flame throwers!

Steve

MaxQ

20th September 2009, 03:04 AM

Working on the escape rocket motor attachment points to the tower legs..careful drilling and placement of screws and washers...not a lot of room for error here...there isn't much surface area to work with.
One slip of the dremel and ..problem.

MaxQ

20th September 2009, 03:11 AM

I have spent a lot of time considering how to attach the escape rocket tower and base ring on the top of the capsule.
Anything scale would probably be a little weak, I thought about various epoxied joints and pins, small threaded rods etc, but I just felt that anything surface mounted and not deeply set inside the structure would have a problem upon opening shock on recovery, i feared it would yank all that minimal stuff right off, given the weight of lead ballast in the nose cone of the escape rocket motor.

There will be lots of lead ballast in the top of the escape motor for future CG adjustment when the outboard cluster of motors is all loaded up.

I hadn't figured this all out when I built the capsule, but being mostly balsa and foam core and posterboard it shouldn't be too hard to deal with.

I elected to drill out three holes on the tower base ring with a very long drill bit...straight through the capsule bulkheads and capsule centering ring.

OK ..its not to scale - and a little bulky, but this is a sport scale model.

Three 12 inch threaded 6/32 rods were inserted, and these will get nuts and washers.

MaxQ

20th September 2009, 03:17 AM

The three rods go through the capsule and exit out the bottom.
You can see the excess length on the rods....
They were long enough to allow me to get the airframe transition part that holds the capsule and drill the centering rings on that part as well......

MaxQ

20th September 2009, 03:22 AM

The rods go through the transition and nuts and washers make for a pretty good compression fit of the whole assembly when tightened down.

This system will also allow for some variabilty - and use of shims to get a 90 degree perpendicular alignment of the tower to the rocket when the time comes to finish this.

Wouldn't have that flexibility if I had just epoxied the stuff in.

MaxQ

20th September 2009, 03:31 AM

A shot of the capsule assembly with hardware in place, minus the capsule nose piece.
This will be dissassembled for painting and reassembly as each of these pieces have different colors.

Now, on to other stuff...

Trim ring on the capsule, a tube coupler for the capsule to mate to the airframe, fin coverings, recovery system hard points and micellaneous details.

U812

20th September 2009, 04:10 AM

Nice Max.

steve

MaxQ

21st September 2009, 02:00 AM

I put some primer on the capsule...things begin to get a little more exciting after you get some paint on a project.

I'll be using old formula Krylon Flourescent Orange on this since I liked it and I still have some from other projects.
The Krylon white primer already on the escape rocket motor was also old formula Krylon as well, so that works out.

The capsule is a very light gray and white, according to the pictures for this version of the Little Joe I'm doing.
I couldn't find a gray color that I liked in Krylon brand - but there are some very light dove grays in Tamiya model spray paints.
So, I'll be using Tamiya.

The boiler plate Mercury capsule got a shot of Tamiya "Mr. Surfacer" gray primer to seal up the paper parts.

When that's dry, I'll use a Tamiya light gray and flat white to finish the capsule.

bsexton

21st September 2009, 12:41 PM

Excellent - looking good!

MaxQ

21st September 2009, 01:43 PM

Excellent - looking good!

I think I see the light at the end of the tunnel....

Several evenings worth of work might get this done for Culpeper.

foose4string

22nd September 2009, 09:17 PM

I think I see the light at the end of the tunnel....

Several evenings worth of work might get this done for Culpeper.

Might we see a Red Glare appearance as well (barring a major setback)????:pop:

Promise, I'll take flight pics!!!!! :eyepop::D

MaxQ

22nd September 2009, 09:40 PM

I sure want to go...especially since work commitments kept me away from the April Red Glare in 2009.

I know you will take excellent pictures!

new2hpr

22nd September 2009, 10:24 PM

MaxQ

22nd September 2009, 11:22 PM

As for your outboards, try the PerfectFlite Minitimer with a breakwire, not the G-switch. Combine that with a few Quest Q2G2 igniters and you're set. Very easy to set up.

I've used the G-switch version and it worked very well to light 3 outboard 38mm G's.

-Ken

I'll look into it...I have two, I thought the second one I bought WAS the "pull pin"/"breakwire" version............. but it has a G switch on it as well.

I desoldered the G switch and pulled it off...based on suggestions here on TRF.
I've never quite gotten either to work for me on a ground test....

PaulB.

23rd September 2009, 05:21 PM

Nice work Jim. I finally decided to get set up here at TRF.
I like the orange/chrome contrast and those fin structures
are killer. :clap:
98mm right? You gonna try that N1666 with the 4 outboard K's?

MaxQ

23rd September 2009, 05:38 PM

98mm right? You gonna try that N1666 with the 4 outboard K's?

Only if Ben provides the motors...........

MaxQ

24th September 2009, 10:45 PM

I elected to reinforce all the fins as experience has shown that these fins take a lot of abuse since they hang below the airframe and hit the ground first.

I spent my build time last night cutting triangular infill pieces with the grain perpendicular to the fin frames and inlaying these in the gaps of the fin framework.
It has added to the weight, but I don't want to have to do post flight fin repairs if I can avoid it.
I'm debating whether to ante up the cash for 1/64 ply sheeting for all sides of the fins....

Got the capsule painted up and it is now on to internal stuff....like an electronics bay for a timer and an internal wire tunnel conduit to the motors...

39mm and 29mm Aerocon motor retention came in for the central motor and two outboards..
Boy they are fast..ordered it last friday and they were here this week.

bsexton

24th September 2009, 11:07 PM

Nice work Jim. I finally decided to get set up here at TRF.
Well it's about time --- welcome to TRF.

bsexton

24th September 2009, 11:18 PM

39mm and 29mm Aerocon motor retention came in for the central motor and two outboards..
Boy they are fast..ordered it last friday and they were here this week.
Do you mean AeroPack?

MaxQ

25th September 2009, 02:48 AM

Do you mean AeroPack?

Uh...yeah. I guess I do (Late night last night).

Can't remember where I came up w/Aerocon....?
I haven't ordered anything from them.

MaxQ

25th September 2009, 04:22 AM

Here are the fins after the additional inlaid support pieces were added.
The leading edge was not very strong until I added these , there's a lot less twist and they're stiffer now.
...skinning comes next.

MaxQ

25th September 2009, 04:25 AM

Capsule got some final paint and the coupler is going on...
I'll wrap a collar around this part.

I'll be extending a piece of MMT from inside the capsule, out the back of this centering ring and attach an eyebolt to that.

I need to do a black trim ring around the foam core edge where the capsule joins the airframe transition.
Thinking about putting the bolts all the way around the transition as well ...think I have time to do that.

MaxQ

25th September 2009, 04:30 AM

Here's the assembled shot - to date - so far....(ahhhhh.....getting closer...)

PaulB.

25th September 2009, 06:00 AM

Looking good-
How about the layer of 1/64th plus one layer FG for the fins?
I think that would be plenty strong....
BTW, Ben said he'll mix up an N-sparky for this one...
:roll:

MaxQ

28th September 2009, 03:12 AM

I wouldn't mind a small sparky...anyone tried a "G" sparky?

Pantherjon

28th September 2009, 04:11 AM

I wouldn't mind a small sparky...anyone tried a "G" sparky?

Yes, yes I have! It is su-weet!:D Gonna have to fire some more the next launch I get to! ;)

MaxQ

28th September 2009, 04:13 AM

Yes, yes I have! It is su-weet!:D Gonna have to fire some more the next launch I get to! ;)

Tell me more..brand name and designation...

Pantherjon

28th September 2009, 04:17 AM

Tell me more..brand name and designation...

It was the CTI Pro38 1 grain G69..Quite a bit of roar out of a 'G' motor! And the sparkies were kewl too!:cool:..Flew my PML Matrix with it..

Gonna try the 29mm G106 - as soon as I get my mittens on a couple of the cases!

PaulB.

28th September 2009, 04:44 AM

Didn't Bruce eventually use a G sparky in his Saucer?

MaxQ

29th September 2009, 01:44 AM

Didn't Bruce eventually use a G sparky in his Saucer?

I hope so...then I can hit him up to borrow his hadware...! LOL

MaxQ

29th September 2009, 02:16 AM

Built the tube coupler for the capsule. A foam core centering ring was cut smaller than the airframe with a modified motor mount tube in the center that plugs into the internal motor mount tube inside the capsule. (just a structural component...not for a motor).

Recovery system hard point will be attached to this on the end....probably will be an eye bolt in a wood plug epoxied in
the end of the MMT in the picture.

The fit is pretty good, although the airframe has taken a little abuse during the build, slightly out of round, but the fit is close enough.

MaxQ

29th September 2009, 02:23 AM

Did the capsule trim ring to cover the exposed foam core edge of the centering ring at the base of the capsule.

First, I glued a poster board strip using wood glue to the foam core edge to protect it from the superglue I was going to use ...then cut a 1/32 inch thick strip of balsa trim ring to go over that.

I wetted out the balsa strip in hot water for a few minutes until it was pliable, then while still damp, bent it around the capsule while tacking it down with super glue... gave it a shot of accelerator, and it was done.
A little sanding sealer will go on it tomorrow after it has fully dried out.

MaxQ

29th September 2009, 02:26 AM

Here's the assembly with the ring and tube coupler...

ben_ullman

29th September 2009, 02:44 AM

MaxQ

29th September 2009, 03:33 AM

Did someone mention something about N motors? ;)

My dad has a Pro38 1G case if u need it Jim. Speaking from experience swept back fins require HUGE parachutes! Im using a 28 foot cargo chute in the Sandhawk. Supposed to bring it in around 10FPS. Im so tired of fixing those dumb things. Especially after getting some color on her.

Ben
<swept back fins require HUGE parachutes! >

Yep...you got that right.
I done my share of fin repair on the other Little Joe...
And that Loc IV has had several years worth of repairs to fin cracks...I bought that kit before Loc had thru the wall fins...surface mounted (ugh!)

Hey thanks,...think that sparky would burn my fins off...?

Pantherjon

29th September 2009, 06:57 AM

They might get a little burn mark on them but I don't think the sparky will burn them off!

Capsule looks awesome!

MaxQ

30th September 2009, 12:11 AM

Well, that shouldn't be a problem..maybe I'll get some flame proof paint....

ben_ullman

30th September 2009, 03:32 PM

Well, that shouldn't be a problem..maybe I'll get some flame proof paint....

No you wont have a problem. As long as you use a standoff. If you let the motor rest about 1-2" off the deflector you will scorch the bottom. If you off set it like 4-6" you will be fine. The G sparky has sparks but there not the long big chunks of Ti like 54 on up use.

Ben

MaxQ

2nd October 2009, 02:27 AM

After referencing photos and debating whether or not to do it...I decided to go for some detailing around the transition...all the little bolts in holes that are at an angle around the trim ring.
Part way through this effort I regretted it.
But I think it turned out ok.

I cut sections of launch lugs at an angle to make a bolt hole collar, plugged them each with a section of wood dowel, and then, after making a pattern with equally spaced bolt locations - wrapped the transition - and then I drilled holes and inserted the bolt assembly.

After that work and a bit of cussing, I trimmed the excess section of lugs off the surface, did some light filling and sanding, and then glued in little decorative bolt heads.

I then masked off the chrome transition for the two step paint job...

MaxQ

2nd October 2009, 02:32 AM

Here's a shot after the flat white primer was applied, some more sanding and filling to fill the little gaps here and there, and then the flourescent orange paint applied to the transition...

The real vehicle had a lot more bolts around the transition, but this is after all "sport scale" and I wasn't into doing twice as many bolts...and I didn't think the chrome posterboard body tube would handle twice as many holes cut into it...
This does give it the impression anyway...

I'll be adding trim ring detail and painting that black...and the capsule needs two orange panels on the base...

MaxQ

2nd October 2009, 02:37 AM

Here' s a close up shot and the overall...

gerbs4me

2nd October 2009, 06:12 AM

wow, the Little Joe looks amazing, great work!

would look so sweet on a sparky

bsexton

2nd October 2009, 01:45 PM

Didn't Bruce eventually use a G sparky in his Saucer?
No, it was a Smokey Sam. But I do have all of the Pro-38 hardware which you are welcome to borrow.

bsexton

2nd October 2009, 01:46 PM

The rocket looks great by the way.

MaxQ

2nd October 2009, 02:24 PM

Thanks..looking forward to a first flight this fall, somewhere.

Culpeper or Red Glare, maybe both if weather and work schedules cooperate.

MaxQ

2nd October 2009, 08:47 PM

Worked on the trim ring and masked off and painted the orange panels on the capsule...
The difference in hue of the orange must be the lighting...looks the same in normal light...

MaxQ

2nd October 2009, 08:48 PM

The launch escape rocket motor got the turnbuckle bolt details to close the gaps in the horizontal bands..

MaxQ

2nd October 2009, 08:51 PM

Couldn't resist this shot...I put the two Joes together for a size comparison....
(the Mercury is 1/12th...the Apollo is 1/18th...size was based on the body tube mandrels I had on hand to roll my own airframes)

U812

14th October 2009, 05:40 AM

Just the best.

Wow.

Steve

I put some primer on the capsule...things begin to get a little more exciting after you get some paint on a project.

I'll be using old formula Krylon Flourescent Orange on this since I liked it and I still have some from other projects.
The Krylon white primer already on the escape rocket motor was also old formula Krylon as well, so that works out.

The capsule is a very light gray and white, according to the pictures for this version of the Little Joe I'm doing.
I couldn't find a gray color that I liked in Krylon brand - but there are some very light dove grays in Tamiya model spray paints.
So, I'll be using Tamiya.

The boiler plate Mercury capsule got a shot of Tamiya "Mr. Surfacer" gray primer to seal up the paper parts.

When that's dry, I'll use a Tamiya light gray and flat white to finish the capsule.

bsexton

14th October 2009, 12:31 PM

I see a drag race in your near future - like Culpeper maybe! :D

MaxQ

14th October 2009, 03:12 PM

I see a drag race in your near future - like Culpeper maybe! :D

Choose your weapons.

I have a Raptor....

bsexton

14th October 2009, 03:18 PM

MaxQ

14th October 2009, 03:32 PM

Well, I meant you could drag race yourself with your Apollo and Mercury projects. But now that you mention it I accept your challenge. I am trying to get some paint on my Raptor so it looks more presentable for the Battle Park launch.

ohhh..don't worry about paint.

Mine still has half the paint burned off from that little incident at Red Glare...

I'd call them battle scars but it was merely my own lack of attention to the forward snap ring.
....but what a lovely display of pyrotechnics it was....

Crazyrocket

14th October 2009, 05:16 PM

It sure was. I'm 2-0 in drag races with you. At some point you need to get that rocket off the pad!

MaxQ

14th October 2009, 05:43 PM

It sure was. I'm 2-0 in drag races with you. At some point you need to get that rocket off the pad!

Much humiliation...

First I was left sitting on the pad with no ignition, then I get ignition - and more than I bargained for......

I must say that replacement igniter the second time did its job....

I wish I had one at VAST this summer as went through everything I could get My hands on and the Loki Red would not light.
I finally got it back in the air on a loki blue.

Maybe we could have a rematch?

MaxQ

15th October 2009, 05:07 AM

...I put this up just to get back on topic.

Working on the fins tonight.
And the electronics bay .....

U812

15th October 2009, 05:20 AM

So cool. So tempting to build one.

Steve

MaxQ

15th October 2009, 05:30 AM

So cool. So tempting to build one.

Steve

Many have...you can too.

ben_ullman

15th October 2009, 05:58 PM

Jim let me know if you need help seating snap rings. i'd be glad to offer my assistance ;)

Ben

MaxQ

15th October 2009, 10:23 PM

Jim let me know if you need help seating snap rings. i'd be glad to offer my assistance ;)

Ben

Thanks! I think I got that down now.
But I'll probably need some help when I get to Ex, (like when casting N motor grains, - on the field....

Uhhh. On second thought.................

MaxQ

19th October 2009, 03:40 AM

Before I skinned the fins I decided to inject some foam ...as you can see a little goes a long way.
Once the excess was trimmed off, the remaining fin skins went on, then leading edge will be sealed and sanded.

The fins need some paint.

Need to get that Electronics bay and conduit instaled...almost done....

sandman

19th October 2009, 05:09 AM

U812

19th October 2009, 06:31 AM

What a machine!

Steve

MaxQ

19th October 2009, 01:39 PM

BTW, I do have the Little Joe I decals. Just the "UNITED STATES" lettering.

They are an extreamly odd stencil that I had to "create" for a customer.

Probably not the correct scale but that is easy enough to correct.

I just need a height and width of one letter to scale it.

I'll get a measurement for you...
Would that be the airframe only, or the capsule as well?
The lettering on the airframe runs vertically, the capsule left to right.... _ x _

sandman

19th October 2009, 03:42 PM

I'll get a measurement for you...
Would that be the airframe only, or the capsule as well?
The airframe runs vetically, the capsule left to right....

Just the airframe.

I could probably do the capsule decals. I just never was asked before.:D

look at the pic. Aren't those stecil letter odd?

Look at the "T" one of them is different than the other two.

"One of these thing is not like the other..."

Initiator001

19th October 2009, 06:10 PM

Gordy,

I took this picture at a Virginia 'museum' a few years ago of the Little Joe 1 they had on display. You may find it useful.

sandman

20th October 2009, 12:05 AM

Gordy,

I took this picture at a Virginia 'museum' a few years ago of the Little Joe 1 they had on display. You may find it useful.

You just have to admit, that is the strangest stencil!

MaxQ

20th October 2009, 02:22 AM

You just have to admit, that is the strangest stencil!

Hey Gordo...

I show a longitudinal length of 12.5 inches from the top of the U to the bottom of the S....
I was hoping my vinyl graphics guy in my neighborhood could get this done, but I'll go with you if you think you can do it.

I'll PM you my info...and let me know how much$

...the capsule horizontal lettering would be great too.

sandman

20th October 2009, 05:00 AM

I have it scaled up for you.

Does anybody know if there is a UNITED STATES stencil on both sides or just on one side?

Pantherjon

20th October 2009, 05:34 AM

Before I skinned the fins I decided to inject some foam ...as you can see a little goes a long way.

Yep, it don't take much!:roll:

Awesome looking project!;)

Initiator001

20th October 2009, 07:17 AM

I have it scaled up for you.

Does anybody know if there is a UNITED STATES stencil on both sides or just on one side?

Both sides, Gordy.

MaxQ

22nd October 2009, 02:15 AM

While I await Sandman's decals, I'm trying to wrap up the external finish of the airframe and capsule, and the internal fittings.

I skinned the foam filled fin structure with some more ply, and with a little sanding and filling on the LE and tips, they were ready for primer.

Quite pleased with the way they turned out, quite stiff and took a good bit of weight in a test. That's a very hefty thick walled PVC tube the rocket is fitted over...(the PVC tube that I turned the posterboard airfame on) - I turned the whole assembly end over end and dropped it down on the fins...the fins and the internal bulkhead held up the weight.

Had to mask off the airframe of course to protect the chrome finish on the body tube.
The white primer will serve as a base for the orange trim on the fin tips and a base for the chrome silver paint for the fins...

U812

22nd October 2009, 02:55 AM

Excellent!

Steve

MaxQ

22nd October 2009, 03:27 AM

Masking and yet more masking...I've used up a lot of masking tape and paper...

MaxQ

22nd October 2009, 03:29 AM

That thin balsa strip "trim ring" around the capsule base that covers up the edge of the foam core centering ring is a real beauty ring now when painted satin black...

MaxQ

22nd October 2009, 03:31 AM

Got the exterior trim paint on the fins, I need to mask again for a white base and then orange on the airframe panels...then I hope I can take a break...

MaxQ

22nd October 2009, 03:51 AM

I promised the wife a vacation, so after tomorrow, I'll be off to the smoky mountains for a week...(that should get me some "green stamps" to go off and do some fall launches later...).

I hope to be back in time to get the finishing touches done for a the fall launch at Culpeper...maybe Red Glare after that....

(In the meantime...I just couldn't resist posting this one.......)

wilsotr

22nd October 2009, 03:54 AM

Gorgeous!

MaxQ

22nd October 2009, 03:56 AM

Gorgeous!

You gotta join us at Culpeper Tim.. I wanna see that project of yours up close...

U812

22nd October 2009, 04:03 AM

Damn what a great job. Jobs!

Steve

MaxQ

22nd October 2009, 04:07 AM

Damn what a great job. Jobs!

Steve

Thanks...!

Meanwhile, my wife just continues to shake her head and roll her eyes everytime I go outside with a rattle can in my hand....

U812

22nd October 2009, 04:10 AM

My wife never misses a lauch and never will. Since Shepard. Me too.

But she thinks they are pretty and likes rockets. She likes my planes too. And the battle ships and sail boats. But the Submarines? She shakes her head at those,

Steve

Mike Howie

22nd October 2009, 07:45 PM

...But the Submarines? She shakes her head at those,

Steve
You should take her to the "submarine races". Maybe then she'll enjoy those
boats more. :p

MaxQ

30th October 2009, 04:58 AM

The decals are on and it is looking good.

Removable escape tower nose got drilled and the nose weight installed.

Cut the electronics bay hatch, and the conduit for the Xavien FIST is in.
Pull Pin ground tests went A-Ok.

accooper

30th October 2009, 12:13 PM

MaxQ

30th October 2009, 03:57 PM

What is weird was that the Little Joe rockets were nothing more than flying trash cans. Cobbled together as cheap as possible. From what I have found out is that they were basicly 6,7, or 8 solid rockets held together by corrugated tin.

But they work wonderfully and allowed NASA to test the escape towers for Mercury and Apollo.

Andrew

<Cobbled together as cheap as possible>

Not too far from the reality of my situation....both of my "Joe" projects used a lot of stuff I just happened to have around the shop...foamcore board, posterboard, and what ever balsa and spruce stock I hapened to have on hand at the moment.

The Apollo Little Joe did require buying a bundle of basswood stick to do those corrugations ...

billspad

30th October 2009, 11:22 PM

MaxQ

31st October 2009, 01:11 AM

I wouldn't see cobbled. There's a lot of stuff under the skin.

When I did the initial sketchs and dimensions for this project - I was going to try and replicate the base structure shown in the photo, inc. the fin root attachment points and the structural ribs and rivets etc. ( I had a photo with a slightly different view...where did you get this one?)

Once I decided to do one central motor in a non scale position for a bit of insurance for stability on a cluster flight - I kind of gave up on the idea....

MaxQ

31st October 2009, 01:15 AM

The last orange panels on each side of the airframe were applied...and the decals from Sandman went on smoothly and really add a nice touch...

MaxQ

31st October 2009, 01:17 AM

The hatch for access to the internal electronics bay is cut and the Xavien board fitted in the compartment...

I have motor retention and empty motor tube blanks to do, and the recovery system hardware, and the aerospike on the escape tower rocket.

I think that's about it.

I'm watching the weather for the Culpeper launch tomorrow and Sunday...I may get a maiden flight in this weekend....hope it is a treat and plays no tricks on me.

billspad

31st October 2009, 03:24 AM

When I did the initial sketchs and dimensions for this project - I was going to try and replicate the base structure shown in the photo, inc. the fin root attachment points and the structural ribs and rivets etc. ( I had a photo with a slightly different view...where did you get this one?)

I paid Boeing a lot of money. They have North American Aviation's archives which contains over 150 photos of the Little Joe booster being built and assembled. They charge about $25 each for a high resolution .tif of the photo. Since I'm on the wrong coast to go look at them I bought 9 representative pictures that they picked out for me.

Once I decided to do one central motor in a non scale position for a bit of insurance for stability on a cluster flight - I kind of gave up on the idea....That's certainly understandable. That's too nice a model to take a chance on a cluster failure.

sandman

31st October 2009, 06:11 AM

The last orange panels on each side of the airframe were applied...and the decals from Sandman went on smoothly and really add a nice touch...

That does look sweet!

You have to admit that is a strange stencil they used! That is not a font, I had to "draw" each individual letter1

rocketguy101

31st October 2009, 04:10 PM

That does look sweet!

You have to admit that is a strange stencil they used! That is not a font, I had to "draw" each individual letter1

When I first saw the pics of the real thing in this thread, I thought "giant dot matrix printer" :D

MaxQ

1st November 2009, 10:11 PM

Well....we got rained out today.
So it's looking like Red Glare VII for this one.

stickershock23

4th November 2009, 10:05 PM

Wow thats incredible! I have a 12" Mercury little joe I have been playing with for quite some time. I think you just inspired me to finish it!

MaxQ

4th November 2009, 11:37 PM

Well, that's what we're here for - in the build threads...

When you get around to doing it, post some pics of your progress!
A 12" Little Joe...sounds real good.

stickershock23

5th November 2009, 02:44 AM

MaxQ

5th November 2009, 03:23 AM

Yeah, as most of you know I have a 10" Mercury Redstone I fly, this would incorporate the capsule and tower from that. so all I have to do is build (how did someone describe it) a cheap tin can booster LOL

I have the tube, centering rings motor mounts fins all cut. its just time putting it all together..

thanks for inspiration !!!! yours looks outstanding!

Can't wait to see launch photos.. that cluster should be AWESOME!

I was planning on 4 54mm's two white and two long burns. to get that real scale flight.

Will something like that be possible in the scale you built? I can't think of any motors like that off hand. accept maybe like 2 c-slot motors and two bates grain motors...

Well, I'm looking for ideas...(I won't be doing any 54mm in this one of course, but the long burn idea sounds good).

Like the scale airplane guys, I think some scale rockets look better with "scale" flight...which on some scale projects means slow liftoffs...

My Apollo Little Joe II took off nice and slow on a central H97, but it was so slow ... the electronics wouldn't trigger the outboard airstarts.

On the last flight , the H123 did the trick and I got the airstarts via the G switch, but it took off a little too fast for my taste.
I'm going pull pin timer now on these projects and I want to try a few cluster motor combos...for maximum flame effect.
Thinking of a central Sparky and whatever - on some of the outboards...