Wildman "Mach 2" Electronics Bay

I have been working on the electronics bay for the Wildman "Mach 2" 54mm minimum diameter rocket. I made a few requirements for myself on this rocket: 1) Redundant Dual Deployment 2) On board Video 3) GPS.

I had a lot of stuff to cram into the electronics bay and began laying things out. The hardest decision for me was the on board video, was I was going to put the camera on the outside or inside. Ultimately I decided what is the point in doing a minimum diameter if I was going to put all the extra drag from an outside mounted camera. Although I will admit I'm not trying to break any altitude records, I wanted the rocket to be more streamline.

This is my "Version 1" and unfortunately I will be making a Version 2 due to damage to the camera window. I used nail polish remover to clean up my epoxy fillets on the camera window, I must have got a drop in between my tape and it appears to have etched the clear polycarbonate tubing. I tested the camera and it messes up the picture badly. The epoxy was long dry before I removed the tape and observed the damage

I guess the point in me making this post is that I will be making a version 2 and am looking for any different ideas for a camera window or a link to better materials that will not be as easily damaged. Also any pointers, pictures, or other helpful advice I am all ears!

E-bay dimensions: Overall length 7'' Switchband 3'' leaving 2'' on both sides for coupling

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I've seen onboard videos of high speed rockets where the camera window melted due to a shock that held in place over the window so you might have been a little doomed to begin with. I'd be interested to see if you could get some tempered glass phone screen protectors to do the job. Maybe try an bend the first one over a mandrel/body tubewith the glue up and then apply the second with glue down over the bent one on bottom. If you can get it to score and break to the right size and bend without cracking it might be actual gold. Try a random one from a dollar store and see what happens. One last thought, round the window corners and try to make it smaller.

How about no window? Just an opening that doubles as one of the av vent holes?

This is without seeing your pictures as they are not showing up on my phone.

Mark pictures are here.

markkoelsch said:

How about no window? Just an opening that doubles as one of the av vent holes?

This is without seeing your pictures as they are not showing up on my phone.

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Pics don't show up for me unless I'm logged in. Probably the same issue for you.

markkoelsch said:

How about no window? Just an opening that doubles as one of the av vent holes?

This is without seeing your pictures as they are not showing up on my phone.

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Are you on branded app on iPad or iPhone? I see them on mobile chrome on iPad. Not on branded app on iPad. I’m looking into that.

Same conditions on android app and mobile browser.

Angie said:

Are you on branded app on iPad or iPhone? I see them on mobile chrome on iPad. Not on branded app on iPad. I’m looking into that.

Same conditions on android app and mobile browser.

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Branded app on iPhone and iPad. That is where I do a very high percentage of my stuff.

Been thinking of taking a break from forum stuff anyways...

Andrew-you did a nice job on constructing your camera bay. If you get a chance look at https://www.multitronix.com/96k-flight.html in which Noah Joraastad launch a 2 stager to > 90,000 feet with a GoPro taking photos horizontally through a "port hole" covered by a sapphire window that he acquired from Esco Optics. Given the small size of his window, I don't believe that the purchase price would be prohibitive. Good luck on the project and please report your progress.

Fred, L2
member of ICBM
Camden, S.C.
KG4YGP

FMarvinS said:

If you get a chance look at https://www.multitronix.com/96k-flight.html in which Noah Joraastad launch a 2 stager to > 90,000 feet with a GoPro taking photos horizontally through a "port hole" covered by a sapphire window that he acquired from Esco Optics. Given the small size of his window, I don't believe that the purchase price would be prohibitive.

Click to expand...

I was kinda surprised at how inexpensive the sapphire is. I doubt it's worth it unless you plan on going REALLY fast but it would definitely work. Another easier solution could be to just leave the factory applied protective film on the plexiglass all the way until launch amd just peel it off once it's on the rail.

UPDATE!

Here is my Version 2 of the electronics bay for the M2 rocket. I'm really happy with how this one turned out, and I'm kind of glad I messed the first one up. I took a different approach this time with the camera window. On the first one I just made a window I knew would be big enough to get a good picture and still be structurally sound.

I wish I had access to fancy CNC machines or routers, but its just me and a dremel! So I figured out where the camera would sit and drilled a small hole. I slowly sanded out the hole bigger with the dremel. I would put the camera in and check the picture until I was satisfied with how it looked. The window is much smaller, and the switchband is smaller, making the rocket smaller overall and should improve performance.

The camera window material I used came from an old phone case I had laying around. I had used the phone case for over a year and the plastic was still in really good shape, so it was already looking more durable than the poly tubing I used last time. I "sandwiched" the clear plastic between the switchband and the coupler this time instead of trying to seal it in place with epoxy like last time. This method was far easier, cleaner, and in my opinion looks much better. I'm slowly making progress, hoping to fly this at Airfest this year for a level 2 attempt.

Andrew,

You did a great job with the dremel! If you told me you used a CNC-I'd believe it. I'd be interested in seeing your photos when available. I did a similar "window" with a dremel in order to view a MARSA 54 L LCD without the need to open the AV bay (https://www.rocketryforum.com/threads/how-to-easily-view-lcd-screen-in-an-av-bay.143018/). I used hose clamps as guides for the dremel cutting wheel. The Dremel isn't the easiest tool to use for precise even cuts. I'm impressed with your ingenuity and I'm quite sure you'll fly through your level 2 certification.
Please post pictures.

Best of luck,
Fred, L2
member of ICBM,
Camden, S.C.
KG4YGP

BUILD UPDATE:

Where to begin. I made some progress, and now I am having to rethink somethings...

The progress made was creating a form of motor retention. I am using the tap'd end of the loki motor to put in a 1/4 eyebolt. I cut a circle of 1/2 inch HDPE (Pretty much the hard plastic a cutting board is made of) that would fit inside the body tube. I drilled 3 equal holes into the HDPE and epoxied in 3 inserts for threads so that I could secure it with tiny threaded bolts from the outside. The finished product was very clean and retained the motor perfectly.

Now for the bad. When testing the fit of my recovery harness above the motor, When I placed the coupler into the airframe it all seemed to fit, when in reality, it slid the closure into the motor to allow everything to fit. Now that the closure was secured from the outside, I do not have enough room for my shock cord and coupler.

Back to the drawing board.

Thought #1) Friction fit the motor. If I did this it would free up enough space for the recovery harness although it would be a tight fit.

Thought #2) Simply order a longer piece of airframe.

Thought #3) Cut down, or use a thinner recovery harness. I had gotten my hands on some 3/16 tubular kevlar for this project and it is currently 15'. Maybe I could get away with 1/8 tubular kevlar? Not sure, will have to do some more research.

Maybe combine thoughts #1 and #2? I'm going to sleep on it before making a decision.

How much room do you have between the coupler and retainer ?

WILDMANRS said:

How much room do you have between the coupler and retainer ?

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From the top of the motor retainer to the bottom of the av bay there is about 1.5 inches of free space. Plus an eyebolt that took up some space.

The coupler seats in 2 inches into the airframe.

I still haven’t made a final decision yet. But Airfest is sneaking up so I better get going!

Good going!

I'm sure you'll get it worked out in time. Trying to enter that Wildman contest and certify at the same time?

Go drogueless... that will save some space. This is a relatively light build, so you may be able to get by with a lighter Kevlar cord... maybe 3/16" braided. You might be able to get 15' of it in 1.5"... if you lose the eyebolt on the AV bay bulkplate and thread it through some holes instead. (Seal them with hot melt glue...)

Nytrunner said:

Good going!

I'm sure you'll get it worked out in time. Trying to enter that Wildman contest and certify at the same time?

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I strongly considered this, but am still talking myself out of it.

I used 1/8 750 lb. braided Kevlar, you save a ton of space over using 1/4.

You can use a couple inch section of body tube, slip it over the motor, slide that into rocket, & let motor hang out back of rocket couple inches, supported by the "spacer"...
That will give you needed room. Been there.

blackjack2564 said:

I used 1/8 750 lb. braided Kevlar, you save a ton of space over using 1/4.

You can use a couple inch section of body tube, slip it over the motor, slide that into rocket, & let motor hang out back of rocket couple inches, supported by the "spacer"...
That will give you needed room. Been there.

Click to expand...

Not if you are in the contest it must be the stock length.

Do 2 mach-2 rockets stacked count? I hear they go really high that way!!!!

WILDMANRS said:

Not if you are in the contest it must be the stock length.

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Does it come with kevlar? It doesn't mention it on the website.

Thorfire said:

Does it come with kevlar? It doesn't mention it on the website.

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Because it does not come with any.

I like that window approach. I'm preparing for a Mach 2 build and considering the options here. Thanks for the inspiration.

could this work with an 808 keychain camera?