Estes Mini Heli question...

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Alan R

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Instructions say to cut 3 slots in the upper part above the hinges.
I read all of it, looked at the pictures, and looked at build threads, but ... what are these for?
Is this strictly for exhaust? Do you need all that?
 

neil_w

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Paging neil_w , got your ears on?
Oh man, I had *just* fallen asleep.
1615000733381.png


Anyway: yes, they're just for exhaust. I imagine they are indeed quite a bit bigger than needed, but it can't hurt. Of course, the way I'm building mine, they'll end up quite a bit smaller. I'm hoping mine won't blow apart. We shall see!

If I were building it stock, I'd leave the slots as-is, but if they were smaller it'd probably be OK too.
 

kuririn

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Sorry Neil.
It was rocket related, so high priority.
;)
 

Alan R

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glad i posted the question. came across this:
 

Alan R

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Gave it the drill bit and a CA edge... drilling cardboard doesn't really work that well.
IMG_0601.JPG
 

BEC

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I modded a couple of these for contest use. One of the things I did was shorten the tube above the hinges and use a single-hole paper punch to punch the holes.

The ejection charge has to get out somehow (after it cooks the burn string that holds the blades closed). That's what the vents are for.
 

GlenP

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Cutting the slots per instructions creates a pretty weak spot on the tube, would probably not survive a lawn dart, I like your choice of three holes instead.
 

Alan R

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The ejection charge has to get out somehow (after it cooks the burn string that holds the blades closed). That's what the vents are for.
Makes me think you could just use a booster motor instead of a charge. lower the string just above the motor and it would burn, no ejection needed
this was probably part of my confusion. I didnt realize the recommended motor had a charge. I was just expecting a booster that did the burn.
 
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kuririn

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Makes me think you could just use a booster motor instead of a charge. lower the string just above the motor and it would burn, no ejection needed
The booster blowby gasses still need to be vented.
The pressure is not as much as an ejection charge but still need to go somewhere.
 

neil_w

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The booster blowby gasses still need to be vented.
The pressure is not as much as an ejection charge but still need to go somewhere.
Also you don't really want the rotors opening up so early.
 

Rktman

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Other reinforcement options would be to add support ribs like with Apogee Components' Heli-Roc, or strengthen the vent area with a coupler.
 
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