Madcow 2.6" Screech

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I may have to get one of these. Sure I have a Vindicator that's fairly similar, but still…
What's it simming at on an I and the K1127?
 
I know it will work but please post a photo of the MMT and the motor case together. Love the short MMT. I have nothing but good things to say about Madcow. Great kits. From the looks of the above I guess I should have ordered one of them as well.
 
I wish Loki was available in Canada... Those cases are gorgeous.... Every time I see a pic of one I want one.

I like how Madcow included all the components for the av-bay. I wish more kit makers did that! I really should get one of there kits at some point. I'll be following this build!:pop:
 
I used the 2.6" screech for my level 1 and level 2 cert, was a blast and went together very well. Looking to put a J760 (put a 54mm motor mount in mine) in it this weekend to push it to Mach 1, will most likely test fly it on a J355 first since I have new electronics in it. If all goes well with the test flight will pack it up and send it up on the J760 . I also used three centering rings on mine as well and pretty much did the same thing you are planning with your cr's.

Ordering parts for a 5.5" 10' version of it and should have most everything by end of next week (I'm hoping), as I am having the fins custom cut. The air-frame, a-bay showed up yesterday. Ordered rocketman shock cords for it today and have sky angle cert-3 chutes on ordered for it as well.
 
Looking good! I am close to wrapping up a build of the same kit. Also picked it up back during the sale. I need to finish a few last things on my av bay, do external fin fillets and then the dreaded chore of painting it. I should get mine in the air in the next few weeks, hoping to spank it on a J at Red Glare in 3 weeks. :)

Jim Z
 
Thanks, I don't mind painting, I actually enjoy it. It's just getting time and good weather to cooperate

Sure you post something about the weather and now its snowing up here...build is looking good.

I'm still tossed up on colors for this one.

I just think red when I think about this rocket.
 
Really nice fillets. Thats the last structural item I need to complete on mine. I expect to ground test my charges this weekend and fly it at Red Glare the following weekend. Continued good luck with yours!

Jim Z
 
Looking good! Mine is still on pace to fly this coming weekend, though not in its final paint scheme. Still undecided in that area and frankly won't have time to do it justice by the weekend.

Have you weighted your build yet? I'm curious what your weight is coming in at. I managed to bloat mine up to a point that I am well over the advertised 32 oz. I don't recall using an excessive amount of epoxy. I did foam the fin can, but that wouldn't explain all the extra weight I am seeing. Fortunately the CG is well ahead of the CP so it will fly fine. Just curious to compare notes when you have a chance to weigh yours. :)

Jim Z
 
I love that color scheme. Artistic creativity is something I sorely lack. I'm just not imaginative in ways to dream up such cool color schemes. Sadly so many of my rockets end up just in primer, or in basic gloss black and white combinations.

Your rocket is on pace to weigh roughly what mine does then. Currently with electronics (Stratologger CF powered by a 9v battery) and recovery, I'm coming in just over 3.5 pounds.

Jim Z
 
3 pounds 2.1 ounces.... no recovery or electronics. This thing should RIP. :)

I could get it done for april, But I've decided If I can't get it painted I'm waiting for may. I have an idea for mine...

16440246294_ceb9438566_c.jpg

Nice,

I have the perfect chute, a Fruity Chute Iris Ultra Compact, but it's 60"...that is my 5 year old on it and he's big for his age.

View attachment 260372
 
Diz,

Much thanks on the fillet procedure. If it is no trouble, I have a thread going regarding my PML Quicksilver and would like some input on some things.
 
expanding on that reply,

I put down aeropoxy along the BT to fin joint, which is fairly long for this kit. Inside the slot I laid in a generous amount of aeropoxy. With that and the One inch radius external fillets of 4500, I believe those fins are in there solid.

Quick question about terminology, I've been wondering this forever, when you say 1" radius fillet, does that mean you used a 2" diameter tool to shape them? Just had to ask, the build looks great!

Nate
 
Any rhyme or reason to the size of the fillet radius/diameter? Is it calculated somehow, or is it just eyeballed for "looks" ?
 
Any rhyme or reason to the size of the fillet radius/diameter? Is it calculated somehow, or is it just eyeballed for "looks" ?

when referring to a partial circle, less than 180° it should be considered a radius not a diameter. in other words, if you cannot easily measure the diameter it should be considered a radius. that being said I also say "I used a 5/8" diameter fillet," just because that was the diameter of the tool used to make the radius.

1/2" radius is pretty beefy, but he plans on really pushing this thing. between the partial TTW fin design and 1/16 G10 thickness he needs a good fillet to keep the fins on. on my 54 mm sport build I think I only used a 5/16" diameter for the fillets. not going to go that fast and the fins are full length TTW. They aren't going anywhere.
 
Any rhyme or reason to the size of the fillet radius/diameter? Is it calculated somehow, or is it just eyeballed for "looks" ?


Actually yes........ [click on it]

optimum fin fillet 6% copy.png

My basis for the different size PVC pipe, used on various diameter tubes, to pull the fillet
 
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That looks fantastic! I think it's time to move away from Rusto. What kind of coverage does the Testors give you? How far does a single can go?
 
I'd have left it all green and have Mark make a sticker in blue that says "tickle my pickle".
 
I tried 2-56 nylon screws in the nose and they just weren't fitting right for me. Fine. Drilled out for 4-40

Hey Dave,

I drilled and taped my 54mm MD for three 4-40 shear-pins then was advised that the 2-56 would be a better choice. So I picked up some 2-56 self clinching nuts and just epoxied them in. I have performed several ground tests without a single failure, Monday is my last one. It was suggested to me not to tap or tighten the shear-pins as it could bind the tubes together, however that has not been my experience so far. I don't torque it down but I do hand tighten the shear-pins and they shear perfectly every time.

If you decide to go back to the 2-56 this is a good solution, below is a 2-56 shear-pin with the self clinching nut.

View attachment 263408

BTW I just mounted my mobius camera shroud on my 3" Dark Star this evening, using the same self clinching nuts epoxied inside the body tube. I like it as I can easily remove the shroud and don't have to fiddle with cramming my hand down the tube to grab the nuts. If you cut the screws off at the same height it leaves a nice smooth inside so there is nothing for the recovery gear to get hung up on.
 
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