Fatty Finn - Fanga’s L3 design and build

[fanga]

And the final step in the build process, I finally finished all the sanding and could give all the rocket parts 2 coasts of clear coat.

I surfaced prepped each of the components using 120 grit paper and a good cleaning with Acetone and lint free wipes. Once done I applied the clear coat using the aerosol can. As per manufacturers instructions, I gave it a light sanding after 30 mins and applied a second coat.

Whilst there are some obvious blemishes around the body, I am more than happy with the outcome and it should be fine for the flight.



Im sure some would not be happy with my choice to go clear coat but I think its great. It also shows off the building process like seeing where epoxy has been applied. A good educational rocket once I have my cert

 

[fanga]

Now onto Assembly and test. More to follow...

 

[Jeremy Sim]

All

Got the electronics completed today, along with a new battery for the Featherweight. After testing all the connections, I placed hot glue over each of the terminal blocks to help secure the connection in place. I also taped up the JST connectors so they don;t come undone during flight.


View attachment 604076View attachment 604077

I will do final testing of the electronics with a

Got the electronics completed today, along with a new battery for the Featherweight. After testing all the connections, I placed hot glue over each of the terminal blocks to help secure the connection in place. I also taped up the JST connectors so they don;t come undone during flight.


View attachment 604076View attachment 604077

I will do final testing of the electronics with a vacuum test

All that room for activities!!

 

[Jeremy Sim]

Just ordered some Proline epoxy for my L3 build, any tips??

 

[fanga]

Just ordered some Proline epoxy for my L3 build, any tips??

Mine came already dyed black and I wasn't expecting it. I didn't check when I ordered what colour it was.

Apart from that I am very happy with it as a construction epoxy. Very easy to work with and easy to do fillets with.

 

[Jeremy Sim]

Mine came already dyed black and I wasn't expecting it. I didn't check when I ordered what colour it was.

Apart from that I am very happy with it as a construction epoxy. Very easy to work with and easy to do fillets with.

Is it thunk like rocketpoxy?

 

[fanga]

It is quite Thunk. I reckon its probably the same consistency. It feels a little more liquid as you are mixing it but when you apply, it stays where you want it to be. I had no problems keeping the fillets formed with Proline.

 

[kjhambrick]

Hey you guys !

What is 'Thunk' ?

Please speak 'Merkin English on this forum

-- kjh

 

[OzHybrid]

I always thought thunk was the past tense of think. I think I thunk that yesterday.

 

[kjhambrick]

That's what I thunk too

EDIT: Hey ! Wait a minute !! I just read your .sig !!! You've rechristened yourself, RocketScientistAustrailia ... nice handle, @OzHybrid

EDIT[ 2 ]: I am glad you kept your John Olsen quote -- that's a keeper

 

[OzHybrid]

That's what I thunk too

EDIT: Hey ! Wait a minute !! I just read your .sig !!! You've rechristened yourself, RocketScientistAustrailia ... nice handle, @OzHybrid

EDIT[ 2 ]: I am glad you kept your John Olsen quote -- that's a keeper

Typing 25 letters anytime I referenced say an SCAD file of mine was taking too long. Down to 8 now.....

 

[kjhambrick]

I always thought thunk was the past tense of think. I think I thunk that yesterday.

I am so thunk !

Never mind, I think thunk just penetrated my thunk head

-- kjh

 

[fanga]

Hey you guys !

What is 'Thunk' ?

Please speak 'Merkin English on this forum

-- kjh

I was assuming it was just a mistype and I just continued on with it.

Could be one of those words they use down below the border

 

[fanga]

Alright was quite a busy weekend but assembly is pretty much all done. I got the rail guides attached by drilling a 4mm hole at each location as per the design.



Once the rear guide was in place I could then attach the thrust plate to the back. First I added the motor retainer using the supplier M4 bolts then I screwed the thrust plate in place to the captive threads on the aft centering ring.

 

[fanga]

I also reassembled the nose cone and attached the forward shock cord using a cow hitch to attach the stitched loop to the eye bolt.

 

[fanga]

Next I lined up the booster extention and used 4 x M4 15mm screws to lock into postiion. I changed the design here and was going to simply epoxy the other coupler in place but found this will be better to access the top motor mount area if needed.

I drilled the required holes 100mm down from the top of the booster tube, this was approx in the middle of the remaining joiner.



I repeated the same process for connecting the forward payload section onto the eBay.




I then did the surface prep as per normal and held them in place using a bolt then applied CA to tack them in place. I then applied epoxy to the nuts to keep them in place. Before applying epoxy, i filled the nut with Vaseline to stop the epoxy from getting into the nut.

 

[fanga]

The last of the assembly was to drill and tap the holes for the sheer pins. I used a 2-54 drill and tap set to achieve this.

 

[fanga]

And here it is, fully assembled, minus the parachutes. I will attache those this week and have a couple of practice goes at folding.

 

[fanga]

Next step is ground tests. We have a few "Catostrophic Fire Danger" days ahead so I might hold off until the temps come back down towards the end of the week.

 

[Jeremy Sim]

Next I lined up the booster extention and used 4 x M4 15mm screws to lock into postiion. I changed the design here and was going to simply epoxy the other coupler in place but found this will be better to access the top motor mount area if needed.

I drilled the required holes 100mm down from the top of the booster tube, this was approx in the middle of the remaining joiner.

View attachment 604839View attachment 604840View attachment 604842

I repeated the same process for connecting the forward payload section onto the eBay.


View attachment 604843

I then did the surface prep as per normal and held them in place using a bolt then applied CA to tack them in place. I then applied epoxy to the nuts to keep them in place. Before applying epoxy, i filled the nut with Vaseline to stop the epoxy from getting into the nut.

View attachment 604844View attachment 604845

Love the idea of using Vaseline to protect the threads!!

 

[Jeremy Sim]

And here it is, fully assembled, minus the parachutes. I will attache those this week and have a couple of practice goes at folding.

View attachment 604848

Well done mate!!

 

[OzHybrid]

When you're testing your chute packing/ejection, just walk it all apart in the order it will be deployed and check for any unexpected pulls on the bridles or chute as you progressively deploy. Once you can do that a few times with no issues, you'll be ready for an ejection charge test. Happy to give you a hand if you need an extra pair of hands.
Norm

 

[fanga]

When you're testing your chute packing/ejection, just walk it all apart in the order it will be deployed and check for any unexpected pulls on the bridles or chute as you progressively deploy. Once you can do that a few times with no issues, you'll be ready for an ejection charge test. Happy to give you a hand if you need an extra pair of hands.
Norm

Brilliant. Thanks Norm. I will use this when checking out the packing.

And thanks for the offer for help. I have a few hands here i can call on,

 

[fanga]

When you're testing your chute packing/ejection, just walk it all apart in the order it will be deployed and check for any unexpected pulls on the bridles or chute as you progressively deploy. Once you can do that a few times with no issues, you'll be ready for an ejection charge test. Happy to give you a hand if you need an extra pair of hands.
Norm

Thanks Norm for this tip. Worked really well yesterday when I tested the recovery.

 

[fanga]

Love the idea of using Vaseline to protect the threads!!

This was a tip from one of my friendly TAPS.

 

[fanga]

Allrighty. Ground tests have been done. Both Drogue and Main charge sizes were able to cause seperation. The main charge may be on the energetic side but it only travels half the length of the shock cord so it should be OK. Attached are the videos. How good is the Blue Raven ground test feature. It's amazing.

Here is a photo of the main deployment showing how far it separated. That was a bit over 1/2 the shock cord length.

 

[fanga]

Here is the charge well packed and ready to fire. I am using High Pressure pipe with cap atatched to the builk head. I then add the charge, an eMatch and then pack with dog barf and seal with masking tape. I also masked off the Wago plugs to help protect them during deployment.



Here is a photo of the well post deployment. Minimal damage and ready to go again.

 

[fanga]

Thats almost it. I need to assemble the motor, which I will do on Friday night. Just paperwork now and the anxiety of waiting for the launch Saturday morning. Aggghhh. It's almost here.

EDIT: Clarifying that I will be assembling the motor in the presence of my TAP.

 

[OzHybrid]

Thats almost it. I need to assemble the motor, which I will do on Friday night. Just paperwork now and the anxiety of waiting for the launch Saturday morning. Aggghhh. It's almost here.

Read the PM I just sent.

 

[rocketgeek101]

Thats almost it. I need to assemble the motor, which I will do on Friday night. Just paperwork now and the anxiety of waiting for the launch Saturday morning. Aggghhh. It's almost here.

EDIT: Clarifying that I will be assembling the motor in the presence of my TAP.

Good luck with your flight! You've built a very a nice looking rocket. I flew an M1830 for my certification flight last year and can attest to it being one hell of an awesome motor!