"Starship" - L3 Build Thread

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Worst case scenario, get familiar with the manual programming feature.
Yeah I don't think it should be too big of a deal. Just looking forward to finally receiving them and setting up the electronics bay. One step closer to launch.
 
Update #17:

Received the 2 Stratologger CFs and battery clips that I ordered last week.

Photo #1: Test fit all of the bulkhead hardware. Tomorrow I will be epoxying the ubolt and charge holders to seal and secure them.

Photo #2: Back view of the bulkhead. Shows the through bulkhead terminals and the ubolt backplate.

Photo #3: Soldered JST connectors to the switches. There is not a polarity to my knowledge when it comes to screwing it into the altimeter terminals. If there is, please let me know.

Photo #4: Temporary mounting of Stratologger CFs. Once I start wiring the electronics bay I will clean it all up with padded zipties instead of hastily applied tape. I may consider moving the Stratologgers closer to the center of the sled but it would make wiring a bit tight.

Photo #5: View of the entire electronics bay. I will be working on the wiring tomorrow. I plan on hooking up the ejection charge wires and battery connectors.

Photo #6: Bulkheads and sled attached to coupler. They fit very nicely, I'm happy with how they turned out thus far.

Looking forward to working more on the wiring tomorrow in addition to epoxying the threaded rod into the nosecone and securing the bulkhead hardware. Progress is being made!20190415_225602.jpeg20190415_225613.jpeg20190415_225712.jpeg20190415_235039.jpeg20190415_235230.jpeg20190415_235436.jpeg
 
Update #18:

Worked on wiring the electronics bay.

Photo #1: Overhead view of the electronics sled, bulkheads, and the coupler.

Photo #2: Side view

Photo #3: Close up of the sled.

Photo #4: View from the other side. Shows the bulkhead and the wiring.

Now that I have everything connected I will be cleaning up the electronics bay and securing the bulkhead hardware. I was able to purchase the USB transfer cord for the Stratologgers so the electronics bay should be correctly configured soon.20190416_224108.jpeg20190416_224123.jpeg20190416_224132.jpeg20190416_224152.jpeg
 
It's also good practice to keep wires short. Not tight, but short enough to avoid unnecessarily large loops, though long enough to allow (only a little) movement. And try to designate wire pathways, as if they are running in imaginary pieces of conduit. I realize that runs counter to keeping them short, but you find a compromise. In other words, keep it neat. That leads to multiple pairs running together over some of their length*, and you can use those areas to apply tie-downs.

And now the other side of the coin. I did write "unnecessarily large loops." Now and then, a large loop is necessary, and so be it. How do you plan to put the while assembly into the coupler? Since there are wires fixed to both bulkheads, you need to be able to break one of them away, and put it back together with the bulkheads prepositioned, which means you need access to a connector in between. The connector just to the left of the sled in the first picture looks like it would be really hard if not impossible to reach in that situation. Maybe you've got this covered; maybe I'm full of hot air. If not, then it looks to me like you need more length between the sled and that connector to allow for final assembly. Less length between the connector and the bulkhead could go along, but no matter what it will need more slack than the other wires in the setup. (If it were me, I'd make that last connection accessible through a hatch in the side of the rocket, but I do tend to overthink things.)

* Some may observe that running wires parallel like this increases interference/cross talk. True, but simply using twisted pairs will be sufficient mitigation, since none of these wires are carrying low level signals.
 
It's also good practice to keep wires short. Not tight, but short enough to avoid unnecessarily large loops, though long enough to allow (only a little) movement. And try to designate wire pathways, as if they are running in imaginary pieces of conduit. I realize that runs counter to keeping them short, but you find a compromise. In other words, keep it neat. That leads to multiple pairs running together over some of their length*, and you can use those areas to apply tie-downs.

And now the other side of the coin. I did write "unnecessarily large loops." Now and then, a large loop is necessary, and so be it. How do you plan to put the while assembly into the coupler? Since there are wires fixed to both bulkheads, you need to be able to break one of them away, and put it back together with the bulkheads prepositioned, which means you need access to a connector in between. The connector just to the left of the sled in the first picture looks like it would be really hard if not impossible to reach in that situation. Maybe you've got this covered; maybe I'm full of hot air. If not, then it looks to me like you need more length between the sled and that connector to allow for final assembly. Less length between the connector and the bulkhead could go along, but no matter what it will need more slack than the other wires in the setup. (If it were me, I'd make that last connection accessible through a hatch in the side of the rocket, but I do tend to overthink things.)

* Some may observe that running wires parallel like this increases interference/cross talk. True, but simply using twisted pairs will be sufficient mitigation, since none of these wires are carrying low level signals.
I wish that I could center the sled more but I can't due to the switch placement. I'm going to work on cleaning up the wiring and twisting the wires. I plan on sliding the sled with the left bulkhead on first then putting on the right bulkhead due to the connections being closer.
 
I apologize for not asking earlier, but how did you install the MMT without the aft CR on and still have it become straight enough?
I epoxied the front centering rings into the body tube using the rear centering ring and retainer (not epoxied) to align it. 20190307_173154.jpeg
 
Update #19:

Photo #1: Drilled 4 vent holes in the coupler. Turns out that the switch mounts are not perfect on the sled so I'll have to make some modification.

Photo #2: Organized the electronics sled, twisting and tying down the wires.20190420_213839.jpeg20190420_214021.jpeg
 
Update #19:

Photo #1: Drilled 4 vent holes in the coupler. Turns out that the switch mounts are not perfect on the sled so I'll have to make some modification.

Photo #2: Organized the electronics sled, twisting and tying down the wires.View attachment 380547View attachment 380548
After fiddling around with it, I found two holes that align with the switches perfectly. I'm picking up some Duracell 9V soon to begin testing. Only thing left to do is to order the recovery system and get to testing.
 
I picked up some Duracell Quantum batteries for the altimeters. I assume these are built the same as the normally Duracell? Have any of you used them?
 
Update #20:

It's been a bit...

Picture #1: Installed batteries. The fit is incredible, very impressed by this sled. I tested the altimeters to make sure my soldering job works, they powered on and did the normal beeps so it is all looking good.

Picture #2: Sealing connections through the bulkhead with tack, I plan on epoxying the ubolt on and sealing around the ejection charge holders. This should ensure that the vent holes are the only openings.

I will post pictures of the sealing method I am using for the 1/4in rods tomorrow. It involves a neoprene washer, stainless washer, lock washer, and a normal stainless nut.20190428_225258.jpeg20190428_225333.jpeg
 
If you're that worried about ejection gas blow through, a little dab of RTV would be much more effective long term. I see most folks just put a dab of 5 min epoxy to keep any hardware from backing out, which seals, too. Either way, not ever seen any issues from simple screw holes.
 
If you're that worried about ejection gas blow through, a little dab of RTV would be much more effective long term. I see most folks just put a dab of 5 min epoxy to keep any hardware from backing out, which seals, too. Either way, not ever seen any issues from simple screw holes.
Yeah I'm probably being a bit over cautious. I'll probably just end up epoxying them as you mentioned when I'm sealing the rest of it.
 
Do you have anything planned to keep the batteries from sliding to the right as shown in your pictures?
 
Do you have anything planned to keep the batteries from sliding to the right as shown in your pictures?
Yes, there are covers that screw on. Just noticed I don't have a photo of them installed so I'll make sure to include one during the next update. The batteries are very secure with the covers on.Battery_Cover_Standard_large.jpeg
 
Sealing the 1/4in rods with a neoprene washer, stainless washer, stainless lock washer, and stainless nut. Provides a very secure connection and seals the hole.20190502_034939.jpeg
 
Update #21:

Changed the parachute combination to an 9ft and 2ft Rocketman Standard Parachute.

Photo #1: Drilled and tapped 6 holes for 2-56 shear pins. I bought a pack of 100 2-56 nylon screws from Amazon for only $4. (https://www.amazon.com/dp/B00137KXGA/ref=cm_sw_r_cp_apa_i_blj2CbASDKP9H)

Photo #2: Close up of the tapped threads. Used tap and t-handle from Amazon.

Tap: https://www.amazon.com/dp/B00N3ZJNIE/ref=cm_sw_r_cp_apa_i_umj2CbD123TJD

T-handle: https://www.amazon.com/dp/B0002YUVSA/ref=cm_sw_r_cp_apa_i_5mj2Cb0SQG60E

I will be ordering the parachutes and shock cord within the next week. Calling around to local stores to see if they have FFFFG black powder for ejection charges, heard it can be hard to find. After that, only thing left to do is ground testing then maiden flight! Looking forward to it.20190511_005624.jpeg20190511_033515.jpeg
 
will be ordering the parachutes and shock cord within the next week. Calling around to local stores to see if they have FFFFG black powder for ejection charges, heard it can be hard to find. After that, only thing left to do is ground testing then maiden flight! Looking forward to it.

Try Bass Pro shops. May have to call a store specifically to inquire, their website is not overly helpful in determining where it is in stock since they won't sell online.
 
Usually smaller, independant gun shops that cater to the muzzleloader crowd are going to have BP. NONE of the corporate box stores in 250 miles of my area (Tidewater VA) carry it.
 
I plan on using the threaded rod in the nosecone for adjustable noseweight but this would impact the T3 GPS tracking system. Some ideas I had were externally mounting the antenna through the nosecone bulkhead, using fiberglass threaded rod, or mounting the T3 on the shock cord but I'm not sure which one would be the best option. What are your opinions on these options?
 
I plan on using the threaded rod in the nosecone for adjustable noseweight but this would impact the T3 GPS tracking system. Some ideas I had were externally mounting the antenna through the nosecone bulkhead, using fiberglass threaded rod, or mounting the T3 on the shock cord but I'm not sure which one would be the best option. What are your opinions on these options?
One option would be Nylon Threaded Rod.
Links to this stuff
Grainger (Link)
US Plastics (Link)
MSC Industrial (Link)
 
One option would be Nylon Threaded Rod.
Links to this stuff
Grainger (Link)
US Plastics (Link)
MSC Industrial (Link)
I wouldn't rely on the nylon threaded rod for all the force but I could epoxy it into the tip so that I can just screw weight onto it. I would have to secure the nosecone bulkhead to a plate inside the shoulder, possibly a 3D printed one.
 
I plan on using the threaded rod in the nosecone for adjustable noseweight but this would impact the T3 GPS tracking system. Some ideas I had were externally mounting the antenna through the nosecone bulkhead, using fiberglass threaded rod, or mounting the T3 on the shock cord but I'm not sure which one would be the best option. What are your opinions on these options?

Get a MAC or APE nose cone bay. Both problems solved.
 
Get a MAC or APE nose cone bay. Both problems solved.
Seems like they are designed for plastic nosecone and do not allow for easily changeable noseweight. It also requires for the top rings to be on the lip between the shoulder and the nosecone, which I already epoxied on. I personally think that it would be easier to use a nylon/fiberglass threaded rod and a ring for the bulkhead to be screwed into. That way the force is not only on the threaded rod, removing a lot of the concern.
 
I wouldn't rely on the nylon threaded rod for all the force but I could epoxy it into the tip so that I can just screw weight onto it. I would have to secure the nosecone bulkhead to a plate inside the shoulder, possibly a 3D printed one.

Not being argumentative here but nylon bolts are a lot stronger then most people realize. Ask any R/C pilot. I have seen nylon bolts used to hold down wings of 1/4~1/3 scale aerobatic planes like the Cap 21 and Christian Eagle.
 
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