Mystic Buzz L1 build and fly

[The Red Darren]

Last week I received my Mystic Buzz kit from Chris' Rockets here in Georgia.

I've started my build and will document for feedback here. For background, I've built and successfully flown an NRC Archer with up to G77 motors.

I could L1 with that rocket, but I'd rather do something "lower and slower" -- plus it's time for something bigger anyway.

Here's the summation of my progress


Level 1 Documentation

Kit: LOC Mystic Buzz (4” diameter rocket)

Motors:

• Level 1 attempt: HW100

Build Details:

• New kit purchased from Chris’ Rockets.
  • Planned modifications:
  • Motor adapters (54mm to 38mm and 29mm).
  • Screw-on, removeable nosecone for future E-bay/Camera/Dual deploy upgrades.
• Received and inspected, verified complete.
• Downloaded instruction manual
  • Read thru completely
  • Test fit all components following the instructions without glue
  • With some sanding of centering rings and fins, all fit snugly and properly
• Motor Tube Assembly
  • Lightly sanded motor tube in centering rings area motor tube to improve bond.
  • Measured, marked, and aligned all centering rings.
    • Four centering rings required proper placement to snugly bind to 6 fins.
    • Dry fit included ensuring proper final alignment with full dry assembly including fins
  • Tacked centering rings (minus the aft ring) to the mount with superglue. Confirmed alignment.
  • Using 30-minute epoxy, glued the centering rings (minus the rear center ring to allow internal fillets) to the motor mount.
  • Built internal fillets around inaccessible points for strength
• Allowed drying overnight
• Tightened and epoxied in the eyebolt
• Installed the shock chord on the eyebolt using the provided sewn loop

• Fig 2: Glued Motor Tube minus aft ring.
• Motor Tube Mounting
• Fit the glued motor tube into the body tube
• Using JB Weld, formed fillets around the accessible centering rings

 

[MarsLander]

Like to see how you are adapting 54 to 29…

 

[The Red Darren]

Good question -- I saw this thing on a at first glance.

https://www.discountrocketry.com/modelrocketsus-29mm-motor-mount-adapter-p-2240.html

If that's not a good option, I have some ideas to make something -- and I haven't started to search the boards yet.

I may only end up doing the 38mm adapter tho... I just want something to give me a range of high midpower options to test fly at my club (probably after my L1 cert).

 

[loopy]

That should be fine. Similar design to the LOC/Precision adapter. Just make sure whatever you pick is compatible with your motor retention.

Plenty of great L2 motors in 38mm, honestly. Don't really need to go down to 29mm from 54mm.

 

[The Red Darren]

It's actually the availability of non-HP "G" motors that is driving 29mm... But that is a decision for much later.

Progress this evening:
The motor tube glued into the body tube and internal fillets done with 30 min epoxy.
Dryfit the fins to ensure they will all go in properly after epoxy cure on the motor mount

Started sanding the seams and mold marks of the nosecone prepping for primer.
Sanded the fins slightly rounding the leading edges, prepping for sealer.

 

[-Slick-Ice]

The H242-6 and I357-8 are my go-to motors for the Mystic Buzz.

Can I suggest picking up an H219? or the 38/240 or 38/360 with RAS kit? I don't think the H100 is enough motor for this rocket. I am seeing 41FPS on the rail and maximum acceleration of 4.6G.

 

[thzero]

i284?

Is a fairly big rocket for Level 1, so you'd have to go up to the lower Is probably to get where you want to be.

 

[thzero]

Might look at the i180, i211 and i284.... but those are all RMS cases. I205 and I140 are single uses, might try those too if you don't have RMS cases.

 

[The Red Darren]

I had not run sims yet and chose the HW100 because it seems a popular choice for similar rockets.

Simming, the HW100 is on the light end of passable -- although my sim shows 5.3G max and 35mph off the rod.

As long as my weight comes in properly, this line looks great to me for a Cert Flight (H219T) -- I can drill it for 8s delay.

Name Configuration: Simulation 4 [H219T-10
Velocity off rod: 57 mph
Apogee: 1374 ft
Velocity at deployment: 39.2 mph (note, motor delay can be drilled to 8s, reducing deployment speed)
Optimum delay: 8.01 s
Max. velocity: 229 mph
Max. acceleration: 13.4G
Time to apogee: 9.04 s

I haven't messed with reloadable motors yet so I'm heavily leaning toward an Aerotech single use for L1. I do plan to buy a reloadable case for my Archer to learn -- but for now the plan is to keep it simple for L1.

Progress today -- finished internal fillets with 30-min epoxy. Dry fit all the fins again to ensure they all fit and no epoxy fouling the seats. Will be gluing the front fins in tonight with JB Weld. I cannot access them to put internal fillets on the front fins. I'll use some generous external fillets on both fin sets for strength.

 

[The Red Darren]

Here's a shot of the front fins glued in and the rear fins tacked.

The blue marks are Rail button locations.

Working on fillets now... best part of the job

 

[waltr]

I haven't messed with reloadable motors yet so I'm heavily leaning toward an Aerotech single use for L1. I do plan to buy a reloadable case for my Archer to learn -- but for now the plan is to keep it simple for L1.

A good single use for L1 cert flight is the H283ST. This is a 38mm motor and has a lowish total impulse of 201Ns. This will increase speed off the rail considerably compared to an H100 and also has a lower total impulse which means flight is not as high which is a plus for recovery.