L2 Cert Build

[Albanach]

Assembling the Avionics Bay. Yes, I got the wrong sled but it is the same length as the proper width one. I also got the ejection charge cups. I needed specialized tools to assemble.


Actual charge is still a work in progress.

 

[Glasspack]

Nice,
... I put the same charge wells on my LVL2 Model..........
If only I could get back to finishing it !!

 

[OverTheTop]

What is a good source for decals? And how do they fair with Mach speeds?

Vinyl stickers survive quite well to M1.8 in my experience. Some of the fine details came off though, as expected.

Burnish the vinyl down onto the airframe properly. I use a teaspoon pushing on the cover paper to accomplish this.

 

[Albanach]

Getting the AV bay together got the proper sized sled. This allowed me to drill the switch holes and vent holes.

 

[David Schwantz]

If I may make a suggestion, cut off the extra thread that is sticking out of your lock nuts. Don't want them to snag on harness. All you need is one thread sticking out of the nylon insert.
Did you print the sled? Looks nice. I have always just used ply for mine, but am envious of the 3D ones.

 

[Albanach]

Will do as you suggest. Bought the sled from Additive Engineering. Although a 3D printer is looking like my next buy for custom parts.

 

[Albanach]

Well, primer and paint arriving today. The fun of getting it right.

 

[FlyBy01]

Well, primer and paint arriving today. The fun of getting it right.

So close you are.

 

[Albanach]

Got the avionics all wired up. Think I need to trim a slot to accommodate the large nut of the eyebolt.

 

[Albanach]

Priming and of course this reveals that I need to work on my fillets.

 

[Banzai88]

Priming and of course this reveals that I need to work on my fillets.
View attachment 483610View attachment 483611

Meh, a tiny bit of glazing putty and some more sanding and it'll be like it never happened.

 

[Albanach]

Meh, a tiny bit of glazing putty and some more sanding, and it'll be like it never happened.

Should be an easy fix. Thanks, SeniorC from an NEM1

 

[Albanach]

Got the paint on it. Realize I had the deluge and main chutes wired backwards.

 

[Albanach]

Anyone have a motor casing I can borrow at MWP and maybe an adapter for 75 to 54?

 

[jd2cylman]

If I am not mistaken the Aero pack flange retainers come with threaded inserts for the screws. 1/8th FG CR is not enough for these to lock into, IMHO. I have used 1/4" ply behind the CR as a backer.

No inserts are necessary. The inserts are just for wood. Just drill and tap the fiberglass and thread the retaining bolts directly into the 1/8" rear ring. I have done it this way on all my 4" 75mmt rockets. Haven't lost a case yet. If your ejection charge is big enough to blow the retainer off the rear CR, you're doing something wrong (or maybe very cool... ).

 

[Adam3836]

Looking great …

 

[Albanach]

No inserts are necessary. The inserts are just for wood. Just drill and tap the fiberglass and thread the retaining bolts directly into the 1/8" rear ring. I have done it this way on all my 4" 75mmt rockets. Haven't lost a case yet. If your ejection charge is big enough to blow the retainer off the rear CR, you're doing something wrong (or maybe very cool... ).

i did just that. Even though I tapped them a few went in hard. And some won’t come out ever again.

 

[jd2cylman]

What case do you need? I'd suggest just buying the AeroPack 54-75mm adapter. Super useful and durable. And then I'd suggest buying a 54/1706 motor case. It's the Swiss Army knife of reload cases.

 

[Albanach]

What case do you need? I'd suggest just buying the AeroPack 54-75mm adapter. Super useful and durable. And then I'd suggest buying a 54/1706 motor case. It's the Swiss Army knife of reload cases.

54/1280, ordered an adapter but supplies are tight.

 

[David Schwantz]

Hi jd, I do not use the threaded inserts myself. But I like to use blind nuts on the backside and the prongs will not hold into the glass CR. Although your way would work also. Might have to try that.

 

[jd2cylman]

54/1280, ordered an adapter but supplies are tight.

I’m sure I have an adapter you can borrow. As long as I remember to throw it in the car.

 

[Albanach]

Ugh paint failure. Was adding a clear coat and this happened. Scrapped away most of the bubbled bits.

 

[Albanach]

Can anyone recommend a universal 75mm casing?

 

[David Schwantz]

I know some CTI motors will fit AT casing, but not sure which ones. If you contact Gary at Off We Go Rocketry he would be able to tell you.

 

[Troy3003]

I know some CTI motors will fit AT casing, but not sure which ones. If you contact Gary at Off We Go Rocketry he would be able to tell you.

Gary is a good fellow to work with.

 

[JSW]

Ugh paint failure. Was adding a clear coat and this happened. Scrapped away most of the bubbled bits.

That STINKS! Happened to me recently. Still can't figure out why. I used the same paint can and clear coat can for two different rockets. Also followed the same painting routine/timing for both. One bubbled up, the other did not.

 

[Albanach]

Well I need to fix my Punisher. Didn’t get enough of a charge in from the motor and crashed it twice. The second time it landed flat.

Finished my L2 cert on the X-4 RuhlStahl.

Went to MWP19 and flew it. Ended up using it for my L2 cert. Flight went pretty well. View attachment 488040

 

[Steve Shannon]

Congratulations on a successful L2. Welcome to higher power!

Unfortunately, I’ve seen quite a few rockets that successfully ground test and then don’t get the chutes out in the air. I’m sorry about the hard landings. Hopefully the repairs go well and you have nice flights from now on.

 

[Orien]

Step 1: Read the instructions.

What are these mysterious texts you speak of?

 

[Albanach]

Well I pulled a Homer and failed to turn on my avionics. This is what is left.