Rocket and Electronics for Airstarts and DD? Recommendations?

[rharshberger]

Conman13 aka Conner is still doing it afaik he just posted a web link not to long ago about it. Sorry I dont have it available.

 

[ThirstyBarbarian]

I just placed my order for the PET2+ and RRC2+ and a few miscellaneous accessories from Missileworks. And I also went to LOC and ordered 2 29mm motor tubes for the airstart motors to be added to the Warlock, and a 54mm electronics bay kit.

I’m thinking I could build the e-bay with the forward end cap bulkhead and allthread permanently glued to the forward end of the e-bay tube. I’ll drill a 54mm hole in the aft plate of the Warlock and permanently glue the e-bay in place with the open end aft. I can insert the sled with the PET2+ timer from the aft end of the rocket and put terminal blocks for the igniters on the end cap. When not using the timer, I can just cap off the bay with a different cap.

Does that sound like a setup that should work for the airstart timer?

I’ll need help figuring out the switch setup. I do not want to turn on a switch from the aft end where I’d be hit in the face if the motors ignited! How would I set it up so I am turning it on from the side? Or is there a remote way to operate a switch? Would a magnetic switch work?

I have an APE head-end altimeter bay that I think I will use for the RRC2+ altimeter. I have seen people use a magnetic switch for these, and I like that idea. It also seems like if it will work for the altimeter in the nosecone, it should work for the timer in the aft e-bay. I’ll need more info on magnetic switches.

Does this sound like a good setup? Please comment. Thanks!

 

[new2hpr]

https://s424.photobucket.com/user/new2hpr/library/Rocketry/Excess In Moderation?sort=6&page=1

Some photos in this link that show my hatch for airstart timer, and conduit to rear centering ring. It's been in a few cluster/airstart threads on here and the archive. Search for Excess In Moderation. I'm no expert, but what I did worked well for me.
-Ken

 

[OverTheTop]

If you are doing multiple motor ignitions for airstarts a Clustomatic might be of use to you. Details here: https://forum.ausrocketry.com/viewtopic.php?f=60&t=5546&start=26


These take the altimeter output and boost it to safely (without frying the altimeter output) ignite your clusters.

Good luck with the project!

 

[ThirstyBarbarian]

https://s424.photobucket.com/user/new2hpr/library/Rocketry/Excess In Moderation?sort=6&page=1

Some photos in this link that show my hatch for airstart timer, and conduit to rear centering ring. It's been in a few cluster/airstart threads on here and the archive. Search for Excess In Moderation. I'm no expert, but what I did worked well for me.
-Ken

Thanks. It looks like a good setup. Since I'm modifying an already-built rocket, do you think it might be easier to do the modification like I described by adding the airstart timer bay in the aft centering ring and accessing it thought the cap than it would be to cut a hatch in the side of the built rocket?

 

[ThirstyBarbarian]

I'm only lighting 2 airstart motors, so I think it probably is not necessary for this project. But that looks like a good item to keep in mind for bigger projects with more igniters.

 

[new2hpr]

Doing a hatch on an already built rocket would be tricky but possible. Stuffing it through the aft centering ring might be the easiest, if you've got room, fitting between fin tabs and motor tubes.
-Ken

 

[ThirstyBarbarian]

Doing a hatch on an already built rocket would be tricky but possible. Stuffing it through the aft centering ring might be the easiest, if you've got room, fitting between fin tabs and motor tubes.
-Ken

That’s what I think too. There’s going to be plenty of room for the airstart module and the motor tubes in the aft centering ring, and the way this version of the rocket was designed fin tabs do not go through to the motor tube, so the fin can is wide open.