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rklapp

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This reminds me of something that's really annoying my lately. With the recent clearance sales at HL, dozens of people have been posting photos on FB of the kits they bought, many dozens. Dudes, I want to see you're built rockets and fly them, not bags of rocket parts. It's not a model until you assemble it, and it's not a model rocket until you put a motor in it and send it skyward, hopefully to recover it. Sorry if I offended. Rant over...
:eggnog:
 

rklapp

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Speaking of which...

Don't miss our Spring Sale from March 21-28!
1616104051322.png
 
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neil_w

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Well it turns out that, not only are the pod tubes incorrectly specified as BT50, and the miter cut template was sized for BT50, the camera-ready BT20 decal art I provided for the pods was resized/redrawn for BT50 as well.

*sigh*

Here is my original artwork at 300 dpi (I always print an extra):
white_decals.jpg


If you don't want to bother with miter-cutting the pods, cut inside the red and use the decals, it will look good. If you miter-cut the pods then also cut inside the black.

Here is a miter cut guide for BT-20, also 300 dpi. Mark the fin line on the long edge of the tube while doing this, to save hassle later:
1616160952313.png

The long side of the pod tubes should be 2.25" long after cutting (the above template should yield that exactly).
 

neil_w

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Glad you got her in the air, sorry for the broken fin.

I'm trying to figure out how you only got 240' on a C11. My sim shows 420', and a 4.3s ideal delay. My flights were definitely way higher than 240'. How much did yours weigh, with/without the altimeter? Mine is 2.9 oz.
 

rklapp

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Glad you got her in the air, sorry for the broken fin.

I'm trying to figure out how you only got 240' on a C11. My sim shows 420', and a 4.3s ideal delay. My flights were definitely way higher than 240'. How much did yours weigh, with/without the altimeter? Mine is 2.9 oz.
I apparently like to build mine heavy. With is 4.4oz and without 4.2oz. I installed a baffle and retainer. The upper section weighs 1.4oz. I didn't paper the fins. They are saturated with sanding sealer. I know this because I can see inside the broken balsa. It was a clean break so easy to glue back with TB2.

Maybe all of my rockets are exceptionally heavy, but I find my altitudes in Hawaii are about 30% less than mainland desert conditions. I suspect it's because the humidity averages 60% with many low wind mornings around 80%. The conditions yesterday were 44% so it was probably the weight of the rocket that was a factor.
 

neil_w

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Well, when I override my OR model to 4.4 oz I come up with 317', 3.9seconds... so that's closer to what you got. Maybe apply the "Hawaii correction factor" and you are where you are.

So I guess C11-3 would be better for yours. A Q-jet D16-4 would step you up to about 500', could be a good choice.
 
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