My Madcow 2.6 Bomarc build thread

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Wally Ferrer

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Honestly it look good enough (primer) on May 5 after 2nd coat of primer. Remember it is meant to fly and will get bang up. Let's see this baby Roar off the pad.
My club is still not launching, but I do hope to have it ready when we do. I would rather it be above 60 degrees (70 is better) when I paint, so I'm trying to be patient with the weather... BUT IT IS HARD. 🤪
 

AfterBurners

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My club is still not launching, but I do hope to have it ready when we do. I would rather it be above 60 degrees (70 is better) when I paint, so I'm trying to be patient with the weather... BUT IT IS HARD. 🤪
Where do you live? I always have decent weather.
 

G-Dog

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We'll have 70's in the mid-atlantic soon enough, and you can't go wrong with the black/white paint scheme in my opinion. I was 'supposed' to be done with the primer on mine by now, but the seam for the BT's isnt up to snuff yet.
Are you going to use the decals with the kit, or go another route ? I'm still debatiing...
 

Wally Ferrer

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We'll have 70's in the mid-atlantic soon enough, and you can't go wrong with the black/white paint scheme in my opinion. I was 'supposed' to be done with the primer on mine by now, but the seam for the BT's isnt up to snuff yet.
Are you going to use the decals with the kit, or go another route ? I'm still debatiing...
I'm going with the kit decals. I still see dings and dents and tiny slivers of spiral here and there, but I'm just giving it another day to dry due to temperature before I start with a bit of white.
 

jrap330

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Ok, don't forget to post a picture of it when it is on your club's pad.
 

Wally Ferrer

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Added white to the wingtips and tail yesterday, but still not cured enough to mask for the black. Maybe tomorrow, it just broke 70 degrees here...

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Wally Ferrer

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After trying to catch up on some household chores, I managed to mask some white areas and spray some black...

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Wally Ferrer

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I gave it another day before I painted the ramjets silver. I now need calculate how much nose weight to add and get that done before finishing the nose cone paint.

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Wally Ferrer

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Thanks, everyone. Now I need to figure out some nose weight and get the cone painted, add some decals and then find a launch... Almost there..!
 

Wally Ferrer

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Rocksim shows the CG at 22.6 inches from the nose tip, Madcow states it should be 23.5 inches. To get the CG at 23.5 inches from the nose tip, it appears I need between .45 and .7 lbs, the heavier being for any H motors. Acme anvil, here I come..!
 
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Nytrunner

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Is the 22" w/o motor?

And the .45 and .7 whats needed to get the CG to 23 with the motor?
 

Wally Ferrer

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Decals are on, slightly off center on the stripes on top of the tunnel, not enough for me to care. Nose cone re-sanded and ready for primer and paint.

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G-Dog

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Rocksim shows the CG at 22.6 inches from the nose tip, Madcow states it should be 23.5 inches. To get the CG at 23.5 inches from the nose tip, it appears I need between .45 and .7 lbs, the heavier being for any H motors. Acme anvil, here I come..!
Wally,

Whats your file giving you as the CP ?? CG's of course will vary from one build to another, but we should both have the same(or very close) CP for the same kit. I always shoot for an accurate CP, then see where the CG ends up and make allowances for epoxy,paint,etc.. I have a CP of 30.6 with the stock components.
 

Wally Ferrer

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Wally,

Whats your file giving you as the CP ?? CG's of course will vary from one build to another, but we should both have the same(or very close) CP for the same kit. I always shoot for an accurate CP, then see where the CG ends up and make allowances for epoxy,paint,etc.. I have a CP of 30.6 with the stock components.
I was just going with the CP from rocksim as I only changed the ramjets, and don't think the shape is different enough to make much difference, so yes, it is listed as 30.8". Going to 23.5" for the CG will be overstable, but it gives me leeway to eventually use a 29-360 I motor/reload and still be ok. I don't have that hardware yet though... ;)
 

G-Dog

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Are you going with nose weight up inside the tip,, or back near the shoulder ?? just wondering...
 

Wally Ferrer

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Glad you asked, G-Dog... I was feeling a little bad for not documenting how I added the nose weight. I drilled a hole in order to add the shot and epoxy. Through that hole, I uses an old launch rod and gouged the inside nose tip quite a bit, to provide something for the epoxy to grab. I mixed up an ounce of 30 minute epoxy and poured it all into the nose cone, keeping it upright with the nose inside a short piece of body tube. I then poured in the shot I had weighed by hanging a cup from the nose tip and added it until the Bomarc was balancing at 23.5 inches with the 29-240 H motor in the rear. That turned out to be .7 lbs, I removed an ounce of that to compensate for the epoxy. I still wonder if I'm too overstable, but I prefer that to not stable. I didn't want to drive screws through the nose, so I got some foam that I'll actually be adding in before I add the red color...
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