# Remove Before Flight Switch

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#### Bruce

##### Well-Known Member
Does anyone sell a complete "Remove Before Flight Switch"?

I was thinking of something that a rod goes into and holds the switch open. When you remove the rod, the switch closes.

It would be ideal to have a complete assembly with the micro switch built in to the part that the rod slides into.

Does something like this exist? Or do you have to make your own?

#### Banzai88

##### Lvl 2, Wallet..even more destroyed
Does anyone sell a complete "Remove Before Flight Switch"?

I was thinking of something that a rod goes into and holds the switch open. When you remove the rod, the switch closes.

It would be ideal to have a complete assembly with the micro switch built in to the part that the rod slides into.

Does something like this exist? Or do you have to make your own?

#### Bat-mite

##### Rocketeer in MD
There are also key switch versions. Aerocon sells them, and the key remains in when off. But they require a 3/4" bore, which is a bit much for any smaller rocket.

#### K'Tesh

##### OpenRocket Chuck Norris
You remove the entire switch? Usually you remove a key or a pin to activate the switch.

#### Steve Shannon

##### Well-Known Member
You remove the entire switch? Usually you remove a key or a pin to activate the switch.
On the LabRat Rocketry ones just the pin with a “Remove Before Flight” flag slides out.

#### cautery

##### Well-Known Member
I am "assuming" that the LabRat switch is based upon a "Normally Closed" microswitch body, to which the add a printed bracket for mount and pull-pin bore?

Nice idea.... provided the switch is rated better than the max current at max voltage the circuit will see.

Could use it as the closure trigger on a N.O. relay, but that starts adding additional failure points and weight.

Would be nice to mount this bore-sighted back away from a vent band hole or other required hole to do double duty.

Same effect should be possible with screw switch and other methods.

Remove Before Flight tag is cool though...

#### Steve Shannon

##### Well-Known Member
I am "assuming" that the LabRat switch is based upon a "Normally Closed" microswitch body, to which the add a printed bracket for mount and pull-pin bore?

Nice idea.... provided the switch is rated better than the max current at max voltage the circuit will see.

Could use it as the closure trigger on a N.O. relay, but that starts adding additional failure points and weight.

Would be nice to mount this bore-sighted back away from a vent band hole or other required hole to do double duty.

Same effect should be possible with screw switch and other methods.

Remove Before Flight tag is cool though...
The micro switches provided with the LabRat setup have three contacts, a normally open and a normally closed contact as well as a common.
As I recall the ratings are plenty, maybe 10 A. They’re not opening under load anyway. The shock and G rating is 50 gees.

#### Cl(VII)

##### Chris Bender, Lab Rat
I am "assuming" that the LabRat switch is based upon a "Normally Closed" microswitch body, to which the add a printed bracket for mount and pull-pin bore?

Nice idea.... provided the switch is rated better than the max current at max voltage the circuit will see.

Could use it as the closure trigger on a N.O. relay, but that starts adding additional failure points and weight.

Would be nice to mount this bore-sighted back away from a vent band hole or other required hole to do double duty.

Same effect should be possible with screw switch and other methods.

Remove Before Flight tag is cool though...
If it helps, this is the manufacturer data sheet for the switches I use. All my kits contain an Omron SS-5GL switch, however, I remove the hinged lever before the switch is snapped into the 3D printed housing. My understanding based on the model number legend in the Omron documentation, is that this effectively renders the switch equivalent to an SS-5 due to the removal of the lever arm mass (i.e. it is just pin actuated at that point)…way easier to source the lever arm version than the bare button.

For what it is worth, I have never received a report of anyone having an over-current related issue with the switches. Not to say it can't happen, given the high C ratings of some LiPo's a dead short situation could result in exceeding the manufacturer spec on these switches...that situation probably exceeds the current rating on most electronics too though.

You can also wire these switches as normally closed or normally open pending which terminals you choose, but yeah, the standard would be set these up as normally closed.

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#### H_Rocket

##### Death by Powerpoint
If you really want to have fun, tape a Remove Before Flight tag to the air frame and leave it on the pad. Makes a great staged picture.

#### cautery

##### Well-Known Member
The micro switches provided with the LabRat setup have three contacts, a normally open and a normally closed contact as well as a common.
As I recall the ratings are plenty, maybe 10 A. They’re not opening under load anyway. The shock and G rating is 50 gees.
Looks like the SS-10.... versions are capable of 10.1 A max.

If it helps, this is the manufacturer data sheet for the switches I use. All my kits contain an Omron SS-5GL switch, however, I remove the hinged lever before the switch is snapped into the 3D printed housing. My understanding based on the model number legend in the Omron documentation, is that this effectively renders the switch equivalent to an SS-5 due to the removal of the lever arm mass (i.e. it is just pin actuated at that point)…way easier to source the lever arm version than the bare button.

For what it is worth, I have never received a report of anyone having an over-current related issue with the switches. Not to say it can't happen, given the high C ratings of some LiPo's a dead short situation could result in exceeding the manufacturer spec on these switches...that situation probably exceeds the current rating on most electronics too though.

You can also wire these switches as normally closed or normally open pending which terminals you choose, but yeah, the standard would be set these up as normally closed.
Thanks, the datasheet helped a lot.... And taking the arm off ILO the armless part does address my concern about g-force/change in momentum induced arm bounce perhaps disclosing a piece of gear in flight..... I realizd its a vey small chance....

IF they use the. SS-5, then I might want to use the printed mount with a replacement switch.... If I go this way...

Thank you both!

#### Cl(VII)

##### Chris Bender, Lab Rat
Looks like the SS-10.... versions are capable of 10.1 A max.

Thanks, the datasheet helped a lot.... And taking the arm off ILO the armless part does address my concern about g-force/change in momentum induced arm bounce perhaps disclosing a piece of gear in flight..... I realizd its a vey small chance....

IF they use the. SS-5, then I might want to use the printed mount with a replacement switch.... If I go this way...

Thank you both!
Be aware, the switches are an EXTREMELY tight fit by design. I ship them assembled as over half of the original beta testers commented that the switches didn't fit, so I figured best to preassemble. They are this tight to ensure that the pin alignment is exactly correct. Because there is real risk of breaking the printed switch housing trying to remove the switch, I can assemble semi-custom kits for you if you ship me the bare SS-10 switches.

#### cautery

##### Well-Known Member
Be aware, the switches are an EXTREMELY tight fit by design. I ship them assembled as over half of the original beta testers commented that the switches didn't fit, so I figured best to preassemble. They are this tight to ensure that the pin alignment is exactly correct. Because there is real risk of breaking the printed switch housing trying to remove the switch, I can assemble semi-custom kits for you if you ship me the bare SS-10 switches.
Sounds great! I have a prototype I'd like y'all to look at, too. Thank you!

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#### speed

##### Well-Known Member
I ordered a few things from him. Black Friday sale. Got my order in like 4 days. Great quality too. Very happy camper!!

#### speed

##### Well-Known Member
If it helps, this is the manufacturer data sheet for the switches I use. All my kits contain an Omron SS-5GL switch, however, I remove the hinged lever before the switch is snapped into the 3D printed housing. My understanding based on the model number legend in the Omron documentation, is that this effectively renders the switch equivalent to an SS-5 due to the removal of the lever arm mass (i.e. it is just pin actuated at that point)…way easier to source the lever arm version than the bare button.

For what it is worth, I have never received a report of anyone having an over-current related issue with the switches. Not to say it can't happen, given the high C ratings of some LiPo's a dead short situation could result in exceeding the manufacturer spec on these switches...that situation probably exceeds the current rating on most electronics too though.

You can also wire these switches as normally closed or normally open pending which terminals you choose, but yeah, the standard would be set these up as normally closed.
Thanks for stellar service, and great products!! Now that i have some of your switch assemblies in hand, i can see using them in every project. I may try a wifi switch at some point, maybe, but these make my life much simpler, thanks man!!

#### OverTheTop

##### Well-Known Member
One of the main advantages of the RBF pin over the WiFi switch is zero current draw when off. High current draw is the main reason I don't use WiFi switches. YMMV.

#### GlueckAuf

##### Well-Known Member
Before I settled on magnet-actuated switches for all my av bays, I used the Omron microswitches Perfect Flite sells along with a brass guide tube and a pull pin to arm/disarm my altimeter-equipped birds. Instead of a flag, I fastened the pin to a neck lanyard I could wear while the rocket was armed.

On one occasion, I lost a rocket so-equipped in a field that was found later that day by another flyer. While I was extremely grateful he’d found it and turned it in, in his attempt to silence the beeping on my altimeter, he tore up the mechanism with a Phillips screwdriver trying to find the screw switch he was certain was in there somewhere. Moral: label the access hole with something like “Insert a 1/8” dowel to disarm altimeter.”

#### Steve Shannon

##### Well-Known Member
Before I settled on magnet-actuated switches for all my av bays, I used the Omron microswitches Perfect Flite sells along with a brass guide tube and a pull pin to arm/disarm my altimeter-equipped birds. Instead of a flag, I fastened the pin to a neck lanyard I could wear while the rocket was armed.

On one occasion, I lost a rocket so-equipped in a field that was found later that day by another flyer. While I was extremely grateful he’d found it and turned it in, in his attempt to silence the beeping on my altimeter, he tore up the mechanism with a Phillips screwdriver trying to find the screw switch he was certain was in there somewhere. Moral: label the access hole with something like “Insert a 1/8” dowel to disarm altimeter.”
You’re exactly right and that’s a good point. This is one reason I am no fan of the metal key switches as well. Ideally any arming device is reliable during rough flights and can be disarmed by anyone who finds it.

#### cautery

##### Well-Known Member
Before I settled on magnet-actuated switches for all my av bays, I used the Omron microswitches Perfect Flite sells along with a brass guide tube and a pull pin to arm/disarm my altimeter-equipped birds. Instead of a flag, I fastened the pin to a neck lanyard I could wear while the rocket was armed.

On one occasion, I lost a rocket so-equipped in a field that was found later that day by another flyer. While I was extremely grateful he’d found it and turned it in, in his attempt to silence the beeping on my altimeter, he tore up the mechanism with a Phillips screwdriver trying to find the screw switch he was certain was in there somewhere. Moral: label the access hole with something like “Insert a 1/8” dowel to disarm altimeter.”
You’re exactly right and that’s a good point. This is one reason I am no fan of the metal key switches as well. Ideally any arming device is reliable during rough flights and can be disarmed by anyone who finds it.
And this also leads me from "anyone can disarm" to putting label(s) somewhere with ownership/contact details and maybe a disarming blurb...

#### Bruce

##### Well-Known Member
One of the main advantages of the RBF pin over the WiFi switch is zero current draw when off. High current draw is the main reason I don't use WiFi switches. YMMV.
How much current does the Wi-Fi switch draw?

#### Buckeye

##### Well-Known Member
On one occasion, I lost a rocket so-equipped in a field that was found later that day by another flyer. While I was extremely grateful he’d found it and turned it in, in his attempt to silence the beeping on my altimeter, he tore up the mechanism with a Phillips screwdriver trying to find the screw switch he was certain was in there somewhere. Moral: label the access hole with something like “Insert a 1/8” dowel to disarm altimeter.”
Quite presumptuous of that guy. Moral: Don't mess with other people's rockets.

#### OverTheTop

##### Well-Known Member
How much current does the Wi-Fi switch draw?
85mA according to the user manual.

#### Grant_Edwards

##### Well-Known Member
I really, really want to order one of those (with the "remove before flight" flag of course) and put it into one of my rockets. I'm slightly discouraged by the fact that none of my rockets contain any electronics. Perhaps my Estes X-Ray clone needs a small 1S LiPo and a handful of LEDs?

#### Reinhard

##### Well-Known Member
You’re exactly right and that’s a good point. This is one reason I am no fan of the metal key switches as well. Ideally any arming device is reliable during rough flights and can be disarmed by anyone who finds it.
"This is the lock picking lawyer, and what I have for you today is this obnoxiously beeping rocket that I found in a field."

For those wondering...

#### tsmith1315

##### Well-Known Member
Ideally any arming device is reliable during rough flights and can be disarmed by anyone who finds it.
And this also leads me from "anyone can disarm" to putting label(s) somewhere with ownership/contact details and maybe a disarming blurb...
An easy way to do that is with a QR code and note to scan it for instructions for disarming, contact info, etc. Most people at a launch have a phone in their pocket, and as long as they have service, this will get them info instantly. I just print them on an inkjet and make a sticker out of it. It would be far better to have Stickershock print a sheet.

This is my lost rocket code, it sends whoever scans it a text with my number as the "from" with a quick message thanking them and contact info. If someone finds it during a launch, they can know who it belongs to before getting back to the flight line. If you want to see how it works, send a PM, and I'll send the pic unedited. You can scan the pic and see the message.

I put this one on the switchband in case anyone wants to see more info about the rocket, this one links to the build thread. Try it out.

#### Steve Shannon

##### Well-Known Member
I already have my name and phone number on my rocket. Just call me.

#### WillMarchant

##### Well-Known Member
Sticker shock does nice labels with contact info. And I’ve been using these https://dynotag.com/ and they have some pretty small scannable stickers.

#### BABAR

##### Builds Rockets for NASA
Google ”return address labels roll” (I don’t want to be seen as promoting a particular product)

#### Tractionengines

##### Well-Known Member
I really like the way @TheTank put the switch in the rocket in this post. Switch plunger is perpendicular to thrust axis...remove before flight flag trimmed for length. Granted it is a 7.5" rocket...lol