Head end dual deploy without a switch band

[RalPh8]

I have essentially a wildman punisher 3 inch kit. There is no switch band for the AvBay/coupler. What is the best way to do head end dual deploy without a switch band for the AvBay/coupler? How do I secure it to the rocket so that it can withstand the thrust from the rocket motor and recovery gear but still separate from both the body and the nose cone when the drogue and the main are released respectively? Do y’all just use a ton of shear pins? Thanks!

 

[cbrarick]

well 6 sheer pins. as for the switch, well, there's all sorts of ways to do that. something internal that you screw or push, or you can get fancy and do something thru the forward closure that you do before you put the nose cone on at the pad. (this is much less common) On my BALLS project, i have a small terminal block that acts as my switch. I feed in the return leg to the block and screw them down prior to putting on the nose cone. it's that way so i can pull 100+ g's.

 

[Art Upton]

The 4" rocket in my Avatar has no switch band. The screw in switches are on the altimeter sled and have a hole drilled into the AVbay section in the Chute Cannon for the screw driver to go thru.

 

[RalPh8]

The 4" rocket in my Avatar has no switch band. The screw in switches are on the altimeter sled and have a hole drilled into the AVbay section in the Chute Cannon for the screw driver to go thru.

Do you mind posting a photo of what you’re talking about? I’m trying to visualize this.

 

[terryg]

Use an eggtimer quantum altimeter that allows you to activate it via wifi.

 

[Art Upton]

Do you mind posting a photo of what you’re talking about? I’m trying to visualize this.

I'll have to dig that part out of my shed and get a picture of it, but here below is a clip out of my launch video.
Fiberglass tube is going to be your chute cannon correct?

The AV/bay is put halfway into that fiberglass chute cannon and I screw it into that tube. Others may glue it, I like things I can take apart later. [Even with Kraft Tubes] There are screw switches in the AV bay on the Altimeter Sled. A hole is drilled thru the Chute cannon tube and the AVbay to allow you to turn them with a screwdriver.

We did not have WiFi switches back then, but today you do , and that would eliminate lining up switches with holes.

Here is a Still from a video of me turning the switch on before that rocket in my avatar was launched. The silver things are screws that hold the AV/bay to the chute cannon. I used way to many of them. Only really needed 3 , aligned with each fin as I do now.

Above my first joint on my finger on the left hand is the other hole for the other screw in switch that is on the other side from the one I am turning with my right hand. Two altimeters, two switches for redundancy. They also served as the AV/Bay vent holes.

 

[cerving]

You don't need a switch band, but you'll have to drill a hole in the body tube through your coupler to match up with your switch. I would recommend NOT drilling the hole through the nose cone. It's a bit trickier than it is with a switch band. Wireless switches are your friend...

 

[Art Upton]

Turning on the other side switch, this lets you see how close the hole is to the end of the chute cannon. The separation point is between the black and the yellow/black checker board.

 

[Art Upton]

You can see the shear pin masking tape cover here that is near the end of the AV/Bay. Just to the right of the wrist band under the black checker.

 

[StreuB1]

@rfjustin does this in many (I believe....?) his builds and I am sure he has lots of pics...

 

[rfjustin]

I have essentially a wildman punisher 3 inch kit. There is no switch band for the AvBay/coupler. What is the best way to do head end dual deploy without a switch band for the AvBay/coupler? How do I secure it to the rocket so that it can withstand the thrust from the rocket motor and recovery gear but still separate from both the body and the nose cone when the drogue and the main are released respectively? Do y’all just use a ton of shear pins? Thanks!

Without a switch band glued to the coupler, the drogue charge will want to force the coupler into the nose cone. @StreuB1 is correct, I have done this with a Wildman cone with no switch band, but with one specific caveat. I glued a half inch wide piece of coupler into the nose cone acting as a permanent stop for the coupler.

I'll grab some pics of said nose cone this evening.

 

[gloy]

For 4.95 on the wildman website why don't you just order one...problem solved.

 

[FredA]

30 seconds with a saw and you got one too.

 

[JeffShort]

I have encountered the same issue on ther rockets and just cut part of the booster or payload tube to use as a swith band.

Obviously doesn't alter te length of the rocket but probably easier than trying to do head end dd.

 

[RalPh8]

30 seconds with a saw and you got one too.

Thanks all who responded. I ended up contacting Tim from Wildman and he said to just get a diamond abrasive blade and put it on my miter saw. Some masking tape around the edges, five minutes later and the job was done. Admittedly, the questioning about how to go about this had in part to do with me never working on premanufactured fiberglass tubes before and not wanting to mess it up.