Leviathing Build for Lvl 1 cert

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Nick Hutton

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A few weeks back I posted in the yard sale for an Estes Leviathon kit that I planned to upspec for a Lvl 1 cert, having read a number of threads where others had done similar things. One of the replies directed me to a forum member Big_Red_Daddy who was selling clone kits.

In the space of a few hrs, I struck up a txt conversation with Toby and upon discovering that postage to my part of the world was a killer, but became bearable with larger shipments, he set about compiling me a dream pack of upspec build parts and assorted kits and pieces he had spare.

Over the next few months I will not only have my Leviathon kit built - complete with parts suitable for HPR, but a Mega Der Red Max clone, a NCR Big Brute clone, an Estes Executioner, a LOC High Tec suitable for a Lvl 2 build plus multiple laser cut fin packs for other PS II kits I have acquired in some random desire to collect them all.

As a fairly new convert to Rocketry, I’m hoping to glean some tips and tricks from the community to help make my Cert build and flight successful 1st go.IMG_0235.jpg
 
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Having been on vacation for a week starting the day after my box arrived, I was keen to get cracking today. Kids went to horse riding camp for a week this morning, so my afternoon was relatively free for rocket assembly.

The kit is pretty comprehensive and includes a fin jig and plywood fins laser cut

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A couple of things are new to me. I haven’t used plywood on any of my LPR or my one MPR builds so far. Also rail buttons are included and I plan to mount both Launch lugs and buttons to give me options. I’m still not sure the best/easiest way to mount the buttons, but multiple threads on the forum this afternoon, I think screwing into the lower CR will be the way forward for the lower button.
 
First up I’ve assembled the motor mount. Having read the official instructions and looked at a few build pics, I decided to line up the motor tube so that it sat flush with the bottom of the fin can with the PSII 29mm retainer on.

What I didn’t think about until after I glued the top two centring rings on, was that it would lift the motor tube up relative to the fin can tube and this would impact on the room available for the coupler. As a result the coupler won’t be exactly even in its spacing between the two tubes, but should still have plenty of purchase in the bottom tube.

Because I’m aiming to fly it on H and maybe I motors, I’m going to do internal fillets. Thus I left the bottom CR off and assembled the motor mount with just the top two rings

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The kit also comes with Kevlar shock cord to tie into the top CR.

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After sanding the leading edges on the fins and dry fitting them using the included jig, I sanded the root edges to achieve a close fit of the exposed edges to the fin can.

I’m planning to complete the whole build using Titebond III, after a discussion with Toby and reading multiple threads. I have been using epoxy for most of my builds so far which is overkill for what they are and the lack of mixing is certainly appealing.

Fitting the fins to the can is certainly the easiest I have experienced to achieve perfect alignment. I’ve tried to concentrate on getting a close fit on the forward root edges to ensure minimal chance of shearing a fin.

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Measure twice or three and put the screw for the top rail button into the center of the top centering ring. I use #6 or #8 x 3/4" fine thread drywall screws. The flat head recesses into the button (my buttons are beveled just for this). Pre drill the holes with a pilot drill just under the diameter of the screw shank.
 
Measure twice or three and put the screw for the top rail button into the center of the top centering ring. I use #6 or #8 x 3/4" fine thread drywall screws. The flat head recesses into the button (my buttons are beveled just for this). Pre drill the holes with a pilot drill just under the diameter of the screw shank.

+1 I usually glue a scrap piece of plywood to the centering ring on the side where the buttons will go so I have a little bigger target.
 
It's been said before, but it bears repeating, in case some advanced algorithm is monitoring the Intertubes.

Estes should definitely bring back the PS2 Builder kits. Fortunately, when they went OOP, I bought three examples of the Partizon; I've only built one so far, but it's become my "old reliable".

The next one is going to have full DD.
 
Agreed. I’ve built a PSII Smoke and this is my 2nd “PSII” build. I’ve also been hovering up the build kits and have managed to get a Partizan, a Ventris, a Super Big Bertha, a Star Orbiter and a MDRM which is being upspecced to 38mm. Still looking for the rest.....
 
I built the Partizon almost entirely per the instructions, with a couple of exceptions:
  • I used 5-minute epoxy throughout
  • Rather than doing the Estes-standard, "rubber-band and a teabag, blow the nose off" recovery, I built it with the nose fixed to the upper ("payload") BT, and made a bulkhead to fit in the coupler, to have it break in the middle, a la "more traditional" HP kits

I regularly fly it on 3-grain CTI "H" motors; it's what I did my L1 on (link to the onboard video in my sig), and it's generally my "workhorse" rocket.
 
It looks like Toby set you up nicely. I love the upgraded parts and the fact he included fin alignment jigs!
 
I’m planning to complete the whole build using Titebond III, after a discussion with Toby and reading multiple threads. I have been using epoxy for most of my builds so far which is overkill for what they are and the lack of mixing is certainly appealing.

Couplers will stick with Tightbond almost every time. White glue or epoxy only if you don't want to end up with a pile of trash.
 
Update on build. Thanks for advice from everyone. I’ve done internal fillets on both the motor mount tube and the inside of the airframe with titebond

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I’ve done external fillets with titebond thick. It seems to shrink a bit when it dries, so I did two runs.

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I’m still new to rail buttons and have taken the advice of the forum and glued some extra wood to the centring rings to drill into.

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Lastly, I’ve installed the lower half of the coupler. I took previously read advice and used epoxy for that part. Went without a hitch and gave a nice even fillet at the interface with the upper CR.

Also, despite it not being designed to look pretty, I’ve filled the spirals with wood putty. Not sure I have the best stuff available, but can’t seem to find Elmer’s or anything similar in these parts.

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Back at work and busy this week, so limited to evening rocketry. I’ve epoxied the top body tube to the coupler. The tubes aren’t a perfect match, so I’ve had to do a fair bit of sanding to minimise the interface line. I then filled it with wood putty along with a small crease near the top.

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I’ve also painted the fins with two coats of sanding sealer and after 24 hrs sanded them back to a nice smooth finish with 320 grit.

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I’m basically ready to prime, which won’t happen till Thursday due to work.

Still hoping for a cert launch on Sunday and I’ve settled on an H115 DM motor. However, I’ve fine tuned my sim on OR and discovered it’s a bit lighter than I expected and is going to go a bit higher than I planned - 670m (2200 ft). No issues with field as it’s a 5000 ft ceiling, but I’m a bit worried about the drift. The kit comes with a 24” ripstop nylon chute and given its a light rocket (700g incl motor) it could go a fair way.

I’ve ordered a JLCR, but would be using it for the 1st time this weekend. I’ve decided to practise 1st with my Nike smoke on an F reload to practice the burrito wrapping technique I’ve read about. How hard is it to learn to use? Also relies on one being in stock as they were listed on backorder, but the retailer here has told me the website stock levels aren’t accurate.

Would people just fly it old school and have chute deploy at apogee or try to master new technology?
 
Back at work and busy this week, so limited to evening rocketry. I’ve epoxied the top body tube to the coupler. The tubes aren’t a perfect match, so I’ve had to do a fair bit of sanding to minimise the interface line. I then filled it with wood putty along with a small crease near the top.

View attachment 388094

View attachment 388097

I’ve also painted the fins with two coats of sanding sealer and after 24 hrs sanded them back to a nice smooth finish with 320 grit.

View attachment 388096

I’m basically ready to prime, which won’t happen till Thursday due to work.

Still hoping for a cert launch on Sunday and I’ve settled on an H115 DM motor. However, I’ve fine tuned my sim on OR and discovered it’s a bit lighter than I expected and is going to go a bit higher than I planned - 670m (2200 ft). No issues with field as it’s a 5000 ft ceiling, but I’m a bit worried about the drift. The kit comes with a 24” ripstop nylon chute and given its a light rocket (700g incl motor) it could go a fair way.

I’ve ordered a JLCR, but would be using it for the 1st time this weekend. I’ve decided to practise 1st with my Nike smoke on an F reload to practice the burrito wrapping technique I’ve read about. How hard is it to learn to use? Also relies on one being in stock as they were listed on backorder, but the retailer here has told me the website stock levels aren’t accurate.

Would people just fly it old school and have chute deploy at apogee or try to master new technology?

What’s the field like? Grassy, rocky, lots of trees or power lines?
If it’s flat and clear I would watch to see how far other flights are drifting and if acceptable just fly it old school.
Then, celebrate your success by launching it again on an I with the Chute Release.
Good luck!
 
Odd, there is quite a difference in the Thrustcurve files, the Rocksim H97 data looks like the H115, but the RASP file is quite a bit different. I'd bet the RASP file is more accurate based on the name and average thrust.

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Anyhoo! The h97 is the "littlest" L1 motor I know ; would be happy to be wrong and find an even gentler one.
 
CTI H90 in the Pro29 3 grain case.
164 N-s and only over 125N thrust for the first 1/8 of a second. A G80 is more oomphy a motor.
 
Nice to see your build thread. Keep up the good work. Any feedback on my kit is appreciated.
 
Another CTI Pro29 3-grain motor that is very low thrust and low impulse is the H54. It has a long 3-second burn.
 
Nice build, I have one of Toby's kits, he does a nice job putting them together for us
 
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