Estes Little Joe I Construction - I like the kit but I have to whine a bit...

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DeltaVee

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Hello There...

As the title implies, I've been building an Estes Little Joe I that I received as a holiday gift more than a year ago. I decided to start building it rather than finish my other rocketry projects since this was given as a gift along with a Super Big Bertha from the Mrs.!

It's a pretty good quality kit save for the lack of the written word in the instructions. I *pine* for the old style instructions that came with Estes kits, which, if you actually read them, left no room for interpretation whereas with the cartoon-like instructions we get now... not so much!

Now that's out of the way I've been trying to build this one with great care etc. as the fin construction (they're cardstock covered balsa frame construction if you were unaware) is somewhat intricate. I followed the directions as indicated...

I have two curmudgeon complaints here:
Upon putting the fins together, in spite of the laser cut main supporting spar, they are slightly different in span... as I discovered when I applied the *carefully* cut cardstock covers to each. The cardstock extends well past the balsa tip plates by slightly different amounts for each fin. No big deal really but the cover photo does not show recessed fin tips... nor does any photo of the LJ-I appear to show such an arrangement. Yes this is minor... I will likely trim away the excess (something NOT noted in the instructions... even via cartoon!) I could leave them this way but the cardstock tips will damage on every landing... so, OFF it comes!

BTW: DON'T use white glue on the cardstock covers the way I did.... it's virtually impossible to get them on without them wrinkling where the glue comes in contact. I used as little glue as possible (whatever that means) but you'll be painting them silver... and that shows EVERYTHING if you don't do something about it. Luckily I have bondo and sandpaper.

The bigger issue I have is that the fins have tabs for TTW construction. A good thing under any circumstances. But the construction is such that the motor hook (spring steel...) is right *underneath a slot*! That means you're gluing this fin to the motor hook... which flexes whenever you insert/remove a motor! I see a fin failure ultimately! Murphy's law: If you fool with something long enough, you'll BREAK IT!! The motor mount construction sets this up... If I were to build this one again, I would change the position of the motor hook so it was between the fins... cutting a new notch in the aft centering ring... and extending the short fin tab by the required amount.
 
Thanks for the information.
Just starting on the Little Joe 2 next week, but I will be building one of these soon.
Keep up on posting your build.
I will find it most valuable
 
Hello There...

The bigger issue I have is that the fins have tabs for TTW construction. A good thing under any circumstances. But the construction is such that the motor hook (spring steel...) is right *underneath a slot*! That means you're gluing this fin to the motor hook... which flexes whenever you insert/remove a motor! I see a fin failure ultimately! Murphy's law: If you fool with something long enough, you'll BREAK IT!! The motor mount construction sets this up... If I were to build this one again, I would change the position of the motor hook so it was between the fins... cutting a new notch in the aft centering ring... and extending the short fin tab by the required amount.

Wow, looking at the instructions and the parts in my kit shows that you’re right on the money and there really doesn’t seem to be enough room for the motor hook at all. Or at least very little room. Couple of possibilities - cover the motor hook with a paper wrap from the provided Mylar ring forward, then slightly notching the fin tab - or - leaving the hook out and friction fit motors. I prefer not to friction fit unless there’s no other way so option one for my MLJ.
 
Another alternative is an 18mm motor retainer..

That would obscure the wonderfully detailed aft bulkhead detail on the LJI kit, though.

Understood on the challenge with the fin tab contacting the motor hook, although that challenge is easily offset by trimming that single fin tab a bit. Another solution would be to omit the engine hook entirely and use tape for motor retention.
 
That would obscure the wonderfully detailed aft bulkhead detail on the LJI kit, though.

Understood on the challenge with the fin tab contacting the motor hook, although that challenge is easily offset by trimming that single fin tab a bit. Another solution would be to omit the engine hook entirely and use tape for motor retention.

A collegue showed me an 18mm retainer that was amazingly slim... I think it was by Rocketarium. From the photo I think it would work beautifully... and there should still be plenty of space for the nozzles... you'd probably need to trim down the other parts a bit tho...

https://www.rocketarium.com/Build/Motor-Retainers

Otherwise, I'd cut a notch centered on one of the holes for the nozzle decor, and place the hook there...
 
Hello There...

As the title implies, I've been building an Estes Little Joe I that I received as a holiday gift more than a year ago. I decided to start building it rather than finish my other rocketry projects since this was given as a gift along with a Super Big Bertha from the Mrs.!

It's a pretty good quality kit save for the lack of the written word in the instructions. I *pine* for the old style instructions that came with Estes kits, which, if you actually read them, left no room for interpretation whereas with the cartoon-like instructions we get now... not so much!

Now that's out of the way I've been trying to build this one with great care etc. as the fin construction (they're cardstock covered balsa frame construction if you were unaware) is somewhat intricate. I followed the directions as indicated...

I have two curmudgeon complaints here:
Upon putting the fins together, in spite of the laser cut main supporting spar, they are slightly different in span... as I discovered when I applied the *carefully* cut cardstock covers to each. The cardstock extends well past the balsa tip plates by slightly different amounts for each fin. No big deal really but the cover photo does not show recessed fin tips... nor does any photo of the LJ-I appear to show such an arrangement. Yes this is minor... I will likely trim away the excess (something NOT noted in the instructions... even via cartoon!) I could leave them this way but the cardstock tips will damage on every landing... so, OFF it comes!

BTW: DON'T use white glue on the cardstock covers the way I did.... it's virtually impossible to get them on without them wrinkling where the glue comes in contact. I used as little glue as possible (whatever that means) but you'll be painting them silver... and that shows EVERYTHING if you don't do something about it. Luckily I have bondo and sandpaper.

The bigger issue I have is that the fins have tabs for TTW construction. A good thing under any circumstances. But the construction is such that the motor hook (spring steel...) is right *underneath a slot*! That means you're gluing this fin to the motor hook... which flexes whenever you insert/remove a motor! I see a fin failure ultimately! Murphy's law: If you fool with something long enough, you'll BREAK IT!! The motor mount construction sets this up... If I were to build this one again, I would change the position of the motor hook so it was between the fins... cutting a new notch in the aft centering ring... and extending the short fin tab by the required amount.
I do believe it's purposefully done so you do trim the card stock back. They should mention that in the instructions for sure. Because every build is different they make the wraps oversize so after trimming it fits all builds.
 
I do believe it's purposefully done so you do trim the card stock back. They should mention that in the instructions for sure. Because every build is different they make the wraps oversize so after trimming it fits all builds.

I know that there is only so much precision in paper and balsa... I just finished trimming away the excess. I probably don't need to state this but I used a brand-spanking-new blade to do the trimming... and when I had to saw at the paper, made sure that it was in the direction of the balsa...
 
I've been building an Estes Little Joe I [...]I have two curmudgeon complaints here:
[...]The cardstock extends well past the balsa tip plates by slightly different amounts for each fin. N[...]DON'T use white glue on the cardstock covers the way I did.... it's virtually impossible to get them on without them wrinkling where the glue comes in contact.
[...]
The bigger issue I have is that the fins have tabs for TTW construction. A good thing under any circumstances. But the construction is such that the motor hook (spring steel...) is right *underneath a slot*! That means you're gluing this fin to the motor hook... which flexes whenever you insert/remove a motor! I see a fin failure ultimately!

Here is a pic of my Little Joe 1 that was built over the winter, almost exclusively with TiteBond II.
A few observations:
  • Cardstock is always bigger than the frame over which it is glued, so trimming is standard practice. Sealing the edges of the exposed balsa and cardstock with super-thin CA both strengthens them, and allows one to sand them smooth before painting.
  • I either read the MMT-to-fin alignment instructions differently, or re-interpreted them in such a way that my motor hook is aligned with one of the long faux-plastic nozzles, and is at 45-degrees to the fins. One of those four nozzles has a cut-out for the motor hook. See pic below:
Estes Little Joe 1.1.jpg
  • I am a big fan of 18mm motor retainers (https://www.rocketarium.com/Build/Motor-Retainers), but there is no way to fit one on this model, so I went with the Estes hook.
  • I saw no easy way to mask and paint the fins on the rocket (disclaimer - I suck at painting, and don't enjoy it much), so I had pre-painted them before gluing them to the airframe.
  • TiteBond II is a great wood glue, but it shrinks when it dries. One place to NOT use it on this model is when gluing motor mount inside the body tube. Even if you are quick and avoid glue "grabbing" before the MMT is fully positioned, the drying TB2 will shrink the airframe around the area when the glue was applied (hard to see in my pic, but visible when you look for it in person).
    • I would recommend using epoxy for MMT, and for the external fin fillets.
  • Overall, this was a far more challenging and rewarding build than the "Level 3" that Estes advertises.
Estes Little Joe 1.jpg
 
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Here is a pic of my Little Joe 1 that was built over the winter, almost exclusively with TiteBond II.
A few observations:
  • Cardstock is always bigger than the frame over which it is glued, so trimming is standard practice. Sealing the edges of the exposed balsa and cardstock with super-thin CA both strengthens them, and allows one to sand them smooth before painting.
  • I either read the MMT-ti-fin alignment instructions differently, or re-interpreted them in such a way that my motor hook is aligned with the one of the long faux-plastic nozzles, and is 45-degrees from the fins. One of those four nozzles has a cut-out for the motor hook. See pic below:
View attachment 410748
  • I am a big fan of 18mm motor retainers (https://www.rocketarium.com/Build/Motor-Retainers), but there is no way to fit one on this model, so I went with the Estes hook.
  • I saw no easy way to mask and paint the fins on the rocket (disclaimer - I suck at painting, and don't enjoy it much), so I had pre-painted them before gluing them to the airframe.
  • TiteBond II is a great wood glue, but it shrinks when it dries. One place to NOT use it on this model is when gluing motor mount inside the body tube. Even if you are quick and avoid glue "grabbing" before the MMT is fully positioned, the drying TB2 will shrink the airframe around the area when the glue was applied (hard to see in my pic, but visible when you look for it in person).
    • I would recommend using epoxy for MMT, and for the external fin fillets.
  • Overall, this was a far more challenging and rewarding build than the "Level 3" that Estes advertises.
View attachment 410749


Thats some nice work there... I'm looking at page 6 of the instructions and step 3 on the "cartoon" instructions clearly shows the motor hook aligned with one of the slots in the drawing... with the faux nozzle holes between the fins. Step 1 of attaching the fins on page 8 makes special note indicating alignment of the "special" fin tab with the motor hook. So it goes... :) That said, you don't HAVE to do what I did and slavishly follow the directions and you seem to have ended up with a nice result. If I were to do it again I would cut a new notch aligned with the nozzle hole...

I think an 18mm Rocketarium motor retainer could work if you trimmed the plastic parts back a bit from the motor tube but cutting a notch 45 degrees from where it is would be a) faster and b) less work!

QQ: did you use gloss or flat black on the capsule? (... we do not call it a "capsule"... this sir, is a spacecraft!!! )
 
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Thanks for this. I think when I get to mine I'll at least look hard at the 18mm Estes screw-on retainer. That will necessitate a longer motor tube but in so doing one should be able to get the retainer just aft of the part that appears to be the thrust structure for the smaller nozzles, though the outer part of the retainer would overlap over the larger nozzles a little I think.

Hmmmmmmmmm.......
 
I think an 18mm Rocketarium motor retainer could work if you trimmed the plastic parts back a bit from the motor tube but cutting a notch 45 degrees from where it is would be a) faster and b) less work!

It's super busy at the aft end of the rocket, after you glue all the pieces and faux nozzles. I don't think you can trim enough plastic to fit the retainer.
Extending the MMT another 1/2" aft and attaching the retainer to the newly protruding end would physically create room for the retainer, and your fingers to work it, but not sure about the looks.

QQ: did you use gloss or flat black on the capsule? (... we do not call it a "capsule"... this sir, is a spacecraft!!! )

After multiple painful experiences with rattle can paints, I've migrated to automotive paints for top coat finishes (usually over Krylon Industrial Tough Coat Light Gray Sandable Primer). Specifically, DupliColor PerfectMatch GM paint matching colors (see pic below).
Nothing magical about GM colors, other than that my local AutoZone seams to carry a wider assortment of GM colors than that of any other make.

For Saturn V, Little Joe 1, and Little Joe II, silver and black paints were "Ultra Silver", "Black Metallic", and "Pure White" (for LJ1 and SatV). Gloss paint provides smoother base for water-slide decal application.
When I need to knock off some of the shine, I spray a few light layers of matte clear-coat, after applying the stickers.
paints.jpg
But that was the easy part.
AutoZone doesn't carry any orange DupliColor automotive paint, so I reverted back to my old inventory of Rustoleum paints, and lived to regret it. A few times over.
Orange top coat wrinkled / alligator-skinned on me on 3 out of 4 fins, including the all-orange fin. I had to sand-off the wrinkled paint, and respray orange areas at least 2 or 3 times. The all-orange fin had to be resprayed 3 times, as orange coat wrinkled again.
That was not fun.

That reminds me - I need to go and find some Orange DupliColor paint!
 
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Has anyone modded this rocket to launch with four minis instead?
 
For what it's worth, step 15 does indicate to sand the edges smooth after the paper skins have been attached. VERY vague. I too miss the old instruction format. When I did mine I shaved the root of the fin tab to clear the motor retention hook and glued all to the aft bulkhead. The assembly is very solid.
 
Well I did finally get it put together... I my just let the fins go as-is, not try to work too hard on it. The fact is that sometime it doesn't pay to do too good a job on a rocket that isn't for competition.... after 5-6 flights (heck with a cato even sooner!) it won't look quite so pristine anyway!!! :) Capsule/Tower painted... (I did paint the tower with rustoleum 2x red... could've gotten away with not at all since the plastic is red...) Of course I did them separately. The body is ready for its coat of primer...

mercury_little_joe.jpg
 
Looks good so far - thanks for all the build tips. I have one in my build pile................................
 
I just looked in @hcmbanjo 's blog and he doesn't mention it (https://modelrocketbuilding.blogspot.com/2019/11/estes-little-joe-1-7255-build-part-13.html) but it does sound like he had to trim down the tab on that fin which is indeed aligned with the motor hook.
Chris, did you notice if your fin tab was mounting directly on the motor hook?

Sorry about the slow response, I didn't see this until this morning.
The motor hook is in line with the root edge of a fin.

E Little Joe 75.JPG

Looking back, the TTW fin tab (root edge) is in line with the engine hook.
On the blog build I did have to sand the fin tab end to allow for the engine hook thickness. (See blog build, Post #13)
The root edge of the fin tab end up above the mylar retaining ring to allow the engine hook to flex out
and slide an engine in without pushing out the fin.
The position of the engine hook is in line with the fin to allow for the diameter and positioning of the part "Z" larger nozzles.

Here's the whole build:
https://modelrocketbuilding.blogspot.com/search/label/E Little Joe 1
 
Interesting. That means that fin tab is glued to the hook, which probably isn't much of a bond if white or yellow glue was used. Might not be an issue considering how much additional stuff is there holding the fin together.

It does seem like this ought to be addressed in the instructions, and/or one fin should cut with a shorter tab.
 
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Interesting. That means that fin tab is glued to the hook, which probably isn't much of a bond if white or yellow glue was used. Might not be an issue considering how much additional stuff is there holding the fin together.

It does seem like this ought to be addressed in the instructions, and/or one fine should cut with a shorter tab.

If you consider the launch lugs to be at 12 o’clock, afadeev rotated his motor mount assembly to align the hook there instead of the instructions mandated 10 o’clock position. That mod puts the Castor Thiokol XM33 motors in the wrong orientation but definitely solves the fin glued to the motor hook dilemma. When I build mine I’m planning on doing it the same way - I’ll sacrifice a bit of scale detail for a better practical outcome every time. If you’re building this kit as a display model (or like Chris does as a demonstration exercise) then the instructions are the way to go - I build to fly so to me it doesn’t matter;)
 
Sorry about the slow response, I didn't see this until this morning.
The motor hook is in line with the root edge of a fin.

View attachment 414612

Looking back, the TTW fin tab (root edge) is in line with the engine hook.
On the blog build I did have to sand the fin tab end to allow for the engine hook thickness. (See blog build, Post #13)
The root edge of the fin tab end up above the mylar retaining ring to allow the engine hook to flex out
and slide an engine in without pushing out the fin.
The position of the engine hook is in line with the fin to allow for the diameter and positioning of the part "Z" larger nozzles.

Here's the whole build:
https://modelrocketbuilding.blogspot.com/search/label/E Little Joe 1

Nice job on the fins... mine won't look that good from that angle.... nor from any angle. I'd never done built up fins before and they are "ok" but not as nice a job as I should have been able to do. Hands are not quite as steady as they used to be it seems.

In the "how on earth could you be so careless?" department:
So yesterday had reasonably nice weather for a change so I reached for the krylon sandable grey primer.... and picked up the krylon gloss smoke grey.... and I didn't notice until it was dry... no joy in mudville last night...
 
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If you consider the launch lugs to be at 12 o’clock, afadeev rotated his motor mount assembly to align the hook there instead of the instructions mandated 10 o’clock position. That mod puts the Castor Thiokol XM33 motors in the wrong orientation but definitely solves the fin glued to the motor hook dilemma. When I build mine I’m planning on doing it the same way - I’ll sacrifice a bit of scale detail for a better practical outcome every time. If you’re building this kit as a display model (or like Chris does as a demonstration exercise) then the instructions are the way to go - I build to fly so to me it doesn’t matter;)


If I were to do this kit again, I'd cut another notch in the aft centering ring for the motor hook and locate it in between the fins and nozzles 45 degrees from it's design location... leaving the nozzles in their proper orientation. It's not like you can hide the hook anyway.
 
If I were to do this kit again, I'd cut another notch in the aft centering ring for the motor hook and locate it in between the fins and nozzles 45 degrees from it's design location... leaving the nozzles in their proper orientation. It's not like you can hide the hook anyway.
Won't it bump into a large nozzle then? Doesn't look like there are a lot of good options back there.
 
Won't it bump into a large nozzle then? Doesn't look like there are a lot of good options back there.

I feel like there is just enough daylight between the large nozzle and the motor tube to accommodate the flex of the hook... but I won't be building another one any time soon... I just purchased the parts from semroc to clone the k21 Gemini Titan that I built when I was 13 years old... (looks ok from 20+ feet away... any closer and YUCK!). That'll be either the next or after the next one.
 
So as neil_w says you can't redux the motor hook 45 degrees from where it is... However... here is mine in a somewhat more finished form... I used Rustoleum 2x metallic aluminum paint (which I must say looks really good considering how un-smooth my primer layer was and all even after sanding etc. It's not like alot of other types of silver paint which always seems to rub off on your fingers when you handle it! Also flourescent orange by tamiya on an undercoating of flat white.... IMG_20200602_155459.jpg

Consulting Rockets of the World for the paint patterns I noted there that the nozzle color is indicated to be the same as the body... and the launch photo *sort* of looks like that is the case. Since I assembled mine completely before painting, silver is how they are going to stay!

Remaining peeves:
1) that dang decal near the capsule is monstrously hard to put on smoothly... mine has a few very small folds and wrinkles! At one point I took it completely off to re-dip it in water. Kudos to Estes though for STRONG decal material... I miraculously didn't bollix the thing entirely.
2) Instructions say to consult the packaging for painting and decal placement. Well since the packaging did NOT show launch lugs visible, I put the main decal 180 degrees from the launch lugs.... Good news: from the decorated vantage point you cant see the lugs. Bad news is that the recommended lug placement (not to mention lenght of the upper one) precludes cutting the second "United States" decal and placing it on the rocket. After that i noted in ROTW, that the "United States" needs to go on both sides.

BUT the good news is that after all that... it doesn't look so bad...
 
Looks great! So did you leave the tail end stock?
Yes I did. It seems a few of my concerns were relatively unfounded. I was in a bit of a reasonless rush to finish it which is why I now have an extra United States decal! But it seems that this decal is exactly the right size for a 1/54th k21 Gemini Titan clone that I'm going to be building sometime over the course of the next year. I will use a black Sharpie to fill in the gaps in the decal!

But for this one, if I had it to do all over again, I'd take far more care assembling the fins.
 
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