Is this a good layout for an ebay bulkhead?

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tibbe

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I'm building a 2.6" Madcow DX3 and space is at a premium. It's also my first dual deployment setup with an ebay. I've included two pictures of how I plan to add the ejection charge canisters and terminal blocks, while leaving space for rods, nuts, washers, eyebolt, and two holes for wires.

Does this layout make sense?IMG_20180705_215149.jpegIMG_20180705_215134.jpeg
 
Looks good from here. It's just like my 5.5" lids only a bit tighter.

Level 2 project: "Long Tom" LOC Cruiser -> stretched Tomahawk CM

If you can get them, brass shell casings make fantastic charge wells for small diameter airframes. That's what I use in 2.5" and 2" tubes.
(although I just run the match leads through a hole in the bulkhead and avoid the terminal blocks)
 
That looks good. Make sure to plug the holes in the bay lid for the wires. I use silicone rtv and others use poster tack.
 
+1
You do have the tie rods much closer than I care for, but the holes seem to be there already. Even with that I would use #10 [3/16] tie-rods, or even #6 to save a ton of space. 1/4 is overkill on this side
 
For me, 1/4-20 wingnuts or thumbnuts make av-bay ends much easier to close.
 
+1
You do have the tie rods much closer than I care for, but the holes seem to be there already. Even with that I would use #10 [3/16] tie-rods, or even #6 to save a ton of space. 1/4 is overkill on this side
The (pilot) holes for the rods came predrilled from Madcow.
 
i would recommend a forged eyebolt, hard to tell from your picture. is it 1/4-20? if you need one PM me and I can mail you one free if you can cover shipping. i have a bunch of them and all they do is sit in a toolbox. thx
 
I seem to remember Mike Fisher (Binder Design) saying something about how metal charge wells could be problematic due to short circuiting of the igniter/ematches. I don't remember where/when he said it, but I took it to heart, and my AV bays use PVC charge wells.
 
I seem to remember Mike Fisher (Binder Design) saying something about how metal charge wells could be problematic due to short circuiting of the igniter/ematches. I don't remember where/when he said it, but I took it to heart, and my AV bays use PVC charge wells.

I cut a thin strip of electrical tape and wrap it around the exposed metal at the base of my igniters when using metal charge wells. It's cheap insurance against a short.
 
I have used aluminum charge wells without an issue. Then again, I could see an issue with both the match his the side of the charge well. Wouldn't take both positive and negative contact?
 
It's an increased risk when you have metal ebay lids, charge wells and allthread. You can accidentally complete a circuit from one charge well the other.
 
Looks good from here. It's just like my 5.5" lids only a bit tighter.

Level 2 project: "Long Tom" LOC Cruiser -> stretched Tomahawk CM

If you can get them, brass shell casings make fantastic charge wells for small diameter airframes. That's what I use in 2.5" and 2" tubes.
(although I just run the match leads through a hole in the bulkhead and avoid the terminal blocks)
Seems like .45 ACP would be perfect. Good thing I have *lots* of those hanging around.
 
Metal charge wells are fine as long as you aware and careful. I've made a few in anodized aluminum for customers. Although the anodization layer helps insulate them better than just bare aluminum. I may offer the anodized aluminum wells in the future, haven't decided yet.
 
Metal charge wells are fine as long as you aware and careful. I've made a few in anodized aluminum for customers. Although the anodization layer helps insulate them better than just bare aluminum. I may offer the anodized aluminum wells in the future, haven't decided yet.

I'll buy a few if you decide to do it.
 
A bit of tape solves the problem.
View attachment 357004
It is not clear from the photo so perhaps you already do this but I would recommend the two ematch heads be insulated from each other. Either by physical space or with some tape between them. Otherwise, if you put two ematches right next to each other you run the risk of touching the positive side on one ematch to the negative side on the other. This can create a short circuit that can result in the ematch not firing. Best to keep them both electrically isolated from each other.
 
It is not clear from the photo so perhaps you already do this but I would recommend the two ematch heads be insulated from each other.

Absolutely!
The inside match has 2 wraps first, thanks for mentioning that, it slipped by me.
 
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