MadCow 3" Sport X L1 Cert Build

[VonRecktofen]

Hi Folks,
Just another BAR here gettin' ready to build a Madcow Sport X for a L1 cert attempt in August/September of this season...
The plan is to build this model and an MDRM Clone Kit, have both on deck for L1 cert. flights, and see if I can get one or both to successfully launch and land on my attempt day...

I'll try to post some pictures along the way as I'm documenting the build as I go along to get in practice for L2 sometime next season....

I guess I just need to learn how to post pictures in a thread first...

Cheers!
Franz in NJ

 

[slothead]

Hi Franz,
I'm about in the same boat. I launched a Madcow Super DX3 on a sub level 1 (G79) and I wasn't at all impressed with the performance (I had also complicated the build configuration). But now I've acquired a 3" Osprey (fiberglass) and I think it will work better for my L1 (and maybe an L2 as well). It won't be until the farmer harvests his wheat - and that won't be until October apparently, unless I want to go out to MD's eastern shore.

Tom in Maryland

 

[VonRecktofen]

Hi Franz,
I'm about in the same boat. I launched a Madcow Super DX3 on a sub level 1 (G79) and I wasn't at all impressed with the performance (I had also complicated the build configuration). But now I've acquired a 3" Osprey (fiberglass) and I think it will work better for my L1 (and maybe an L2 as well). It won't be until the farmer harvests his wheat - and that won't be until October apparently, unless I want to go out to MD's eastern shore.

Tom in Maryland

Hi Tom,
I had considered a Madcow Super DX3 as well, but while looking at models on their site, I stumbled over the Sport X, which kind of looks like a Nike Smoke airframe with a regular nose....It's still a cardboard/solid wood fin model, but hopefully I'll build it strong enough to withstand the challenge of an CTI H87...

Best of luck in your new build!

Franz in NJ

 

[VonRecktofen]

This is what I got when I tried to post a photo from Flickr

 

[JonathanOtt]

Looking forward to your build thread. I'm planning on adding a MC Sport-X to my fleet this year.

I think it looks like the Centuri/Estes/Semroc Hornet (that's how I'm going to finish it, it Hornet yellow & black with Stickershock decals.)

 

[Bat-mite]

This is what I got when I tried to post a photo from Flickr

I believe Flickr now charges a fee for allowing other sites to link to their content.

 

[VonRecktofen]

I’m gonna try to post some pictures of the build here...
Here is what we are building... Madcow 3” Sport X rocket...

 

[VonRecktofen]

Ok now this is working on the mobile App....
First is the 38mm MMT forward centering ring epoxied in and nylon shock cord strap sewed on the the eye ring...

 

[VonRecktofen]

Then rail button guide line is placed, then fwd and rear centering rings are marked on the airframe tube...
Then the fins are tried in to mark the position of the Aeropack 38mm motor mount

 

[crossfire]

welcome back Franz.

 

[VonRecktofen]

Next, the fins are removed and the MMT Fwd centering ring is epoxied into place, not bonding in the rear ring yet...
Fillets are added to both sides of the Fwd ring with epoxy...

 

[VonRecktofen]

While waiting for the MMT epoxy to set, I installed the payload bay coupler, eyebolt, and plywood plate with epoxy as well...

 

[VonRecktofen]

Then once the MMT fwd ring is set, I put the un bonded rear ring back in, and then tacked the fins into place with thin CA

 

[VonRecktofen]

After the fins are tacked in, the rear MMT ring is again removed so that the internal epoxy fillets can be placed, trying to keep it off the exterior of the MMT and the internal surface of the airframe body tube... It will be easier in the 4” tube of the MDRM clone kit for sure!

 

[VonRecktofen]

After all the internal fillets are on the fins and the MMT, the rear centering ring is epoxied to the fins and the internal airframe body tube, taking care to keep it off the MMT where the Aeropack retainer will go...

 

[VonRecktofen]

Then the first two fin fillets were laid in with epoxy with a monoject plastic syringe....

 

[VonRecktofen]

While waiting for the fin fillets to dry (the MDRM will only have 3 fins-6 fillets) I decided to assemble the upper payload bay... I want to leave options open to allow for an internal onboard 808 keychain camera mount and Altimeter Two (or Three if they come back in stock), so I ordered a bag of medium plastic rivets from MC... Marked out 3 lines spaced around the nosecone and payload coupler, drilled them with 5/32 bit, and lined them up with witness marks... The black rivets will be hidden in the black checkered roll pattern on the payload bay...

 

[VAXman]

Hi Folks,
Just another BAR here gettin' ready to build a Madcow Sport X for a L1 cert attempt in August/September of this season...
The plan is to build this model and an MDRM Clone Kit, have both on deck for L1 cert. flights, and see if I can get one or both to successfully launch and land on my attempt day...

I'll try to post some pictures along the way as I'm documenting the build as I go along to get in practice for L2 sometime next season....

I guess I just need to learn how to post pictures in a thread first...

Cheers!
Franz in NJ

Franz,

Bring them to the CENJARS picnic launch Aug. 5. We can then discuss the when and where of your L1.

FWIW, my Estes MDRM has been flown on a CTI 164H90 to just shy of 1,300ft @ RR's launch site. My MDRM is pretty much stock save for 1/32" birch veneer, 2oz fiberglass and laminating epoxy on the fin's struts in lieu of the 1/8" balsa wood sandwich. I don't know which MDRM clone you're building, so YMMV.

If you fly the Sport X, I'll lend you a sonic alarm depending upon where you fly the L1. August/September is late in the growing season for the NJ launch site farms. Crops (corn, soy, etc.) can make recovery location difficult should your flight land in those crops.

Sent from my SM-T560NU using Rocketry Forum mobile app

 

[VonRecktofen]

Franz,

Bring them to the CENJARS picnic launch Aug. 5. We can then discuss the when and where of your L1.

FWIW, my Estes MDRM has been flown on a CTI 164H90 to just shy of 1,300ft @ RR's launch site. My MDRM is pretty much stock save for 1/32" birch veneer, 2oz fiberglass and laminating epoxy on the fin's struts in lieu of the 1/8" balsa wood sandwich. I don't know which MDRM clone you're building, so YMMV.

If you fly the Sport X, I'll lend you a sonic alarm depending upon where you fly the L1. August/September is late in the growing season for the NJ launch site farms. Crops (corn, soy, etc.) can make recovery location difficult should your flight land in those crops.

Sent from my SM-T560NU using Rocketry Forum mobile app

Elo Brian,
I got the AMW MDRM clone kit, and to my eye, the body tube looks too long and the nosecone is too short... Any idea of where to find a better proportioned nose?

Thanks for any ideas!
Franz

 

[Nytrunner]

What is that, a 3" tube? You're well on your way to making it plenty strong for an L1. An H120 threw my 5lb 4" Patriot to 1360', so it would be a fantastic flight in your sport X

 

[VonRecktofen]

Today the “weapon” arrived... Thank you Apogee Components for shipping me the CTI H87.... Hopefully it will be a successful flight....

 

[slothead]

So you must have acquired an adapter (29-38). I missed that.

 

[VAXman]

Today the “weapon” arrived... Thank you Apogee Components for shipping me the CTI H87.... Hopefully it will be a successful flight....View attachment 357947

How too much was the HAZMAT? I could have saved you a couple of $s because I was thinking of placing an order for some smaller motors. In quantities, the HAZMAT is easier to bear.

Hopefully, if mother nature doesn't throw another weekend tantrum, I'll see you at the picnic launch.

 

[slothead]

A Hazmat from Apogee is $34 now (I think it’s standard). I bought 4 reloads from them just a couple weeks ago for that much of a Hazmat.

 

[VonRecktofen]

So you must have acquired an adapter (29-38). I missed that.

Yes I’ve already received the 38/29 adapter, I’ll show that mocked up in the next set of photos!

 

[VonRecktofen]

How too much was the HAZMAT? I could have saved you a couple of $s because I was thinking of placing an order for some smaller motors. In quantities, the HAZMAT is easier to bear.

Hopefully, if mother nature doesn't throw another weekend tantrum, I'll see you at the picnic launch.

I bit the bullet earlier in the week and ordered this motor from Apogee because it seemed all the smaller H motors were all out of stock... Was getting nervous that come flight time, nothing suitable would be in stock...But yeah, too much for essentially a ziplock sealed plastic bag, in a box, signed by a person....

I’ll keep the “ordering together” technique in mind for my next go-round for bigger motors.... Who do you normally order your bigger “charges” from?

 

[Nytrunner]

I use CSrocketry since chris is the vendor for my regional HPR launches. That's the real trick to avoiding hazmat.

Ask around when you go to fly for L1. See what vendors attend locally and buy from them. Most likely you can preorder for pickup at a launch.

What I want to know is, why so small? You're barely poking your nose into H territory with the H87.

 

[markkoelsch]

Hi Folks,
Just another BAR here gettin' ready to build a Madcow Sport X for a L1 cert attempt in August/September of this season...
The plan is to build this model and an MDRM Clone Kit, have both on deck for L1 cert. flights, and see if I can get one or both to successfully launch and land on my attempt day...

I'll try to post some pictures along the way as I'm documenting the build as I go along to get in practice for L2 sometime next season....

I guess I just need to learn how to post pictures in a thread first...

Cheers!
Franz in NJ

Might I recommend that you do quite a few L1 flights before going to L2. There is A LOT you can and should learn before going L2 motors. I think you should look into electronics and dual deployment before your L2 and many rockets can REALLY have some kick ass flights on L2 motors. You should also get into and pretty much master some form of tracking whether RDF or GPS.

 

[markkoelsch]

Ok now this is working on the mobile App....
First is the 38mm MMT forward centering ring epoxied in and nylon shock cord strap sewed on the the eye ring...View attachment 357790View attachment 357791View attachment 357792

That is nylon harness, right? You will absolutely want to wrap that in a nomex sleeve, or better yet replace it with tubular Kevlar. Nylon does not deal with the heat of ejection well.

Also, is that eye bolt a standard eyebolt, or is the eye welded shut? This is a potential point of failure that I would deal with. A cast eye, a welded eye, a small u bolt, or epoxying the harness to the motor mount can all work.

I realize I just popped a couple posts in here in rapid succession- just trying to impart a lot of collective experience in a hurry.

What will this rocket weigh with motor?

 

[VonRecktofen]

I use CSrocketry since chris is the vendor for my regional HPR launches. That's the real trick to avoiding hazmat.

Ask around when you go to fly for L1. See what vendors attend locally and buy from them. Most likely you can preorder for pickup at a launch.

What I want to know is, why so small? You're barely poking your nose into H territory with the H87.

Well, I keep reading about how much easier it is to go "low and slow"on an L1 cert flight, so I figured that the H87 will help me achieve just that....I don't want to just lob this thing to Kingdom Come on it's first mission...The plan is to get the weight correct so that this littler guy doesn't go completely out of sight (all though I'm sure it will tough enough to see as it is), and get him back in one piece so that I can really start lofting him with bigger stuff when I get more experience....

Keep in mind, the last time I was into Model Rocketry (in 1977), the biggest thing that I had flown was an Estes Maxi Brute Pershing on a "Mighty" D-12-5! This "E, F, G, H," and beyond is all new uncharted territory for me! I've got an AMW 4" MDRM Clone kit on the bench right behind this 3" Sport X, and from what I read, that will handle a whole lot more motor, and let me reach new heights...
I just want an easy, safe L1 cert flight, and then go from there!
As for motors available on site at our local launches, the club where I will be flying my attempt I've never been to before, so I'm not quite sure who or what is available so I thought I should be prepared with something that would qualify and go from there!

Thanks for the info!

Cheers, Franz in NJ