Screw Switch Awesomeness!!!

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hognutz63

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At least in my eyes. My 12 year old daughter's look of indifference said otherwise. However I thought I'd share. I have used Featherweight screw switches in the past and either glued them to the inside of the av-bay coupler or mounted them to the backside of the sled. In the first method I always was worried about stresses on the wires from one end of the wires being stationary. It was easy to arm though. The other way, I felt better about not fatiguing the wires, but felt like I was playing a carnival game trying to blindly hit a #2 screw head in the middle of an av-bay.

So my solution? First off, when I saw the Missle Works screw switches, I really like the fact that they were bigger than the Featherweight version and had the solder tabs for wires or compression terminals. So, after a little thought, here was my solution to mounting one easily. A piece of 3/8"x3/8" square basswood stock, 2 #4x1/2" wood screws and a piece of popsicle stick and a little wood glue, I came up with this.ImageUploadedByRocketry Forum1459643381.694936.jpgImageUploadedByRocketry Forum1459643403.825587.jpgImageUploadedByRocketry Forum1459643416.464502.jpg
 
At least in my eyes. My 12 year old daughter's look of indifference said otherwise. However I thought I'd share. I have used Featherweight screw switches in the past and either glued them to the inside of the av-bay coupler or mounted them to the backside of the sled. In the first method I always was worried about stresses on the wires from one end of the wires being stationary. It was easy to arm though. The other way, I felt better about not fatiguing the wires, but felt like I was playing a carnival game trying to blindly hit a #2 screw head in the middle of an av-bay.

So my solution? First off, when I saw the Missle Works screw switches, I really like the fact that they were bigger than the Featherweight version and had the solder tabs for wires or compression terminals. So, after a little thought, here was my solution to mounting one easily. A piece of 3/8"x3/8" square basswood stock, 2 #4x1/2" wood screws and a piece of popsicle stick and a little wood glue, I came up with this.View attachment 287019View attachment 287020View attachment 287021


Looks good, and I like the Missleworks switches myself. Heres a view of my current builds electronics sled and screw switches.

L3Build119.jpg L3Build138.jpg L3Build139.jpg
 
Looks good (as does the first posting). I'm not familiar with the Missleworks switches, does the little 'screwdriver guide' part come with it, or did you fabricate that yourself?

I make them myself, using Plastruct tubing, the outer piece goes full length, and then the other two pieces are maybe .5" long and are placed inside the long tube. iirc the outer tube is a .375 dia .062 wall, and the inners are .031wall, .25" dia OD, and .188" OD (I can get measurements later if needed, the tubes I have had for years in my modeling bits collection).
 
The guides are awesome. Can you show a picture not installed?
 
I make them myself, using Plastruct tubing, the outer piece goes full length, and then the other two pieces are maybe .5" long and are placed inside the long tube. iirc the outer tube is a .375 dia .062 wall, and the inners are .031wall, .25" dia OD, and .188" OD (I can get measurements later if needed, the tubes I have had for years in my modeling bits collection).

But how are they securely attached?
 
suggest you check out eggtimers wifi switches and their quark altimeter that included wifi controls. I cant go back to using switches- i am so happy with these products. gGreat flights yesterday- and everything safely activated by my phone with charge status displayed.
 
The guides are awesome. Can you show a picture not installed?

While I don't have any uninstalled ones I can show you how they are made, the outer tube is a .375" OD and a .315 ID (actually 1/32" wall tubing) which fits over the #6 screw head with a little slop, then while holding the outer tube (its also the long tube) I put a bead of epoxy around the base of the tube and on the board. Next I cut two pieces of the smaller two sizes of tubing about .25" long each and nest them together with bit of CA or better yet Plastic Welder type cement, I then carefully insert these two pieces as deep into the .375" tube as I want too, and tack in place with cement/epoxy on a tooth pick or other small stick. Its a good idea to double check that the mounting screws are still removable, the nylon washers may now be permanent ( I won't find out until after my L3 flight). The last picture is kind of a reverse order of whats inside the tube. The guide tubes seem pretty strong as is, but after my pre-cert flight I will know for sure, if they are not strong enough then I will add some triangular pieces on the sides all the way down to the sled.

L3Build140.jpgL3Build141.jpgL3Build142.jpgL3Build143.jpgL3Build144.jpgL3Build145.jpgL3Build146.jpg
 
I have used the Missile Works Screw switches on a number of builds including my L3 bird. I solved the issue of "finding" the screw head on the switch by using Marette wire nuts to funnel the screwdriver into the screw head. Cheap, fast, easy. Just grind the small end flat, drill a hole and epoxy over the screw of the switch. Here are pics of two different builds.

P1070987 (Large).JPG P1070932 (Large).JPG Prep for epoxy.JPG P1070919 (Large).JPG

P1100349 (Large).JPG P1100350 (Large).JPG P1100582 (Large).JPG
 
I have used the Missile Works Screw switches on a number of builds including my L3 bird. I solved the issue of "finding" the screw head on the switch by using Marette wire nuts to funnel the screwdriver into the screw head. Cheap, fast, easy. Just grind the small end flat, drill a hole and epoxy over the screw of the switch. Here are pics of two different builds.

View attachment 287313 View attachment 287315 View attachment 287314 View attachment 287316

View attachment 287317 View attachment 287318 View attachment 287319

I like it! I like mine too, but having options is great!
 
While I don't have any uninstalled ones I can show you how they are made, the outer tube is a .375" OD and a .315 ID (actually 1/32" wall tubing) which fits over the #6 screw head with a little slop, then while holding the outer tube (its also the long tube) I put a bead of epoxy around the base of the tube and on the board. Next I cut two pieces of the smaller two sizes of tubing about .25" long each and nest them together with bit of CA or better yet Plastic Welder type cement, I then carefully insert these two pieces as deep into the .375" tube as I want too, and tack in place with cement/epoxy on a tooth pick or other small stick. Its a good idea to double check that the mounting screws are still removable, the nylon washers may now be permanent ( I won't find out until after my L3 flight). The last picture is kind of a reverse order of whats inside the tube. The guide tubes seem pretty strong as is, but after my pre-cert flight I will know for sure, if they are not strong enough then I will add some triangular pieces on the sides all the way down to the sled.

That's pretty ingenious Rich! Held in my onenote for future reference!
 
I have used the Missile Works Screw switches on a number of builds including my L3 bird. I solved the issue of "finding" the screw head on the switch by using Marette wire nuts to funnel the screwdriver into the screw head. Cheap, fast, easy. Just grind the small end flat, drill a hole and epoxy over the screw of the switch. Here are pics of two different builds.

View attachment 287313 View attachment 287315 View attachment 287314 View attachment 287316

View attachment 287317 View attachment 287318 View attachment 287319

I have never seen one with a hole in the bottom. I assume you grind it flat and the drilling is to remove the metal and create a hole to remove the top/bottom?
 
suggest you check out eggtimers wifi switches and their quark altimeter that included wifi controls. I cant go back to using switches- i am so happy with these products. gGreat flights yesterday- and everything safely activated by my phone with charge status displayed.

$2.95 for the missleworks switch, why would I want to spend $20 for a switch I have to build?
 
So that you can turn it on and off without walking to the pad? (I don't own one, I'm just saying....)

No messing with switchbands and extra wiring. Connect the battery wires and secure. Button up ebay and step away.

Only deal is can't do this as easily with carbon fiber rockets. Sucks up Rf and range is possibly decreased. If one has a large ebay, they can use their standard deployment electronics with a WiFi switch. If it's a small project, use a Quantum WiFi deployment altimeter. No switches, no lining up a hole so one can put a screw driver or nut driver in to turn it on. And.............This is the biggie........... Instant ground test-ability of deployment charges remotely! You try that with a 38mm MD rocket without butchering the airframe to run temporary external wires for testing. Kurt
 
That is one good reason. Not standing 10 inches from a rocket while arming comes to mind and i see no need to bring a ladder out with me to climb way up trying to insert or remove a tiny screw. How are those battery's holding up as it was a long wait (love seeing my voltage realtime) How do you feel turning off the rocket with live charges? (I have had to return to the bench when my altimeter was not performing correctly) Some altimeters take a screws intermitents (and wire twisting) while being inserted as a time to fire. I can safely arm and safe my rocket from a safe distance. Did you check your continuity before arming- its on my screen. On the quantum (integrated wifi switch and altimeter) if i Need to test a match... enter test mode and i can remote fire any charge i wish. I am a reformed screwswitch user. In the field i have had the nut cone desoldered and have had to go back to twist and tie. I have stripped threads before. i have dropped the screws into the dirt. I might consider one (their is one quality switch out there but it is fairly good sized) for a large rocket- perhaps as a shunt. I mean no disrespect to the originator of this thread as he has an elegant solution to his problem and he has shared a great method. I dont tend to use screw switches in my rockets anymore. I do agree that it is a bit of work to build these but they are nowhere near as costly as the rest of my rockets gear. Thanks for bearing with me- i am passionate about amazing products and love reading about others cool solutions such as how this thread began[emoji111]️
 
I know you think they are the cat's meow, but they are not for everone. Regarding your post...

1. A switch band is never required.
2. What extra wiring?
3. The ebays of all rockets I fly are prepared in advance. There is no messing with them at the launch.
4. Lining up a hole is nothing.
5. You run the wires out the vent. There is no butchering the airframe

I will say that I love my Eggfinders and have several, so it has nothing to do with who sells them. I am sure they are a quality product. However, I would never have any use for one given the current state of what is available. It is an extra and unnecessary component increasing the possibility of something going wrong.

I also think the MW switches are great. Here is one in an interstage coupler.

68.jpg
 
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1. A switch band is never required.---------------So you use an internal tube coupler epoxied inside for a thrust block on the ebay? I've done that for a recessed keyswitch and I don't trust the little rivets to hold everything in place.

2. What extra wiring? ------ Ummmm, the wiring that goes from your manual switch to your devices. That's the extra wiring. Yeah, one doesn't lose anything if they use a remote WiFi switch to connect up their own altimeter
but a Quantum is a deployment device with monitoring all rolled into one. True one pays with higher current requirement and not smart to turn on the night before because of that but if one is using a deployment device with
separate power for pyro AND the electronics, if they run one battery to both circuits, unless both are switched (more hardware) the battery might be sucked dry by juice running through the continuity circuit even with the
altimeter power "SWITCHED OFF". I've seen it with LED's during testing. Direct wire the pyro battery to the device and the LED's are glowing softly even though the main power to the electronics are TURNED OFF! One must
know their devices. Two power sources = two switches = PITA with likely a marginal addition of safety if at all.

3. The ebays of all rockets I fly are prepared in advance. There is no messing with them at the launch.---- So are mine so I can fly more rockets. I'm going to design my remote ones to remove the bottom bulkhead, plug and secure the battery and ready to go with a remote switch or Quantum onsite. Not so bad and be able to read "all" of the major data right now after the flight.

4. Lining up a hole is nothing.---- Oh yeah. What size hole? On big stuff one can be off a bit but try it on little stuff and measure thrice (if you's got a decent measuring device) and cut once. I have to look at an angle to get a view of some LED's in some ships. TIP: can mount screw switches on the aft bulkhead and use a tight form fitting hole. Screw the switch "on" maybe apply a little clay or putty and a duct tape patch. Lower onto top of rocket (a smaller one of course) and ready to go. Has worked for me for 6 years.

5. You run the wires out the vent. There is no butchering the airframe.---- Unless there are 3 very small ports in a small rocket. Easier to mount the WiFi electronics and go test. With minimum diameter and internal screw retention block it's a heck of a lot easier to carry out testing without ripping or stressing external wires. Especially with apogee charge testing. Kurt
 
Loving the pics here... I usually have no trouble finding my two screw switches, except on one of my rockets... Definitely soaking up the ideas here and will be solving my problem. Thanks, all!!
 
search for "jst 2 connectors". Ebay and Amazon have big bundles- these things are very useful so dont get just ten pairs as they get used up fast[emoji106]
 
search for "jst 2 connectors". Ebay and Amazon have big bundles- these things are very useful so dont get just ten pairs as they get used up fast[emoji106]

Thank you! That was the hardest part. Knowing WHAT to call them! Founds lots of results. Thank you very much!
 
I mount my Perfectflite screw switches directly to the airframe of my fiberglass and cardboard rockets. C'sink the outer airframe if you're worried about finish. I have done this on some of my birds.

That being said... I'm wondering if the FG airframes have some conductivity as I've had some of my altimeters spontaneously turn on from time to time. Rather strange. I need to investigate.

-Mike
 
Ok stupid question. WHERE can if find the two wire connectors?! I want them in my ebays and would rather buy some in bulk to have on hand. I keep finding big auto 2 pin connectors. Nothing like you have pictured here. really want some with a lock tab.

I get them from Doghouse Rocketry. They come in many colors and wire lengths and Bill will do custom colors too (like a black/red wire connector).

Disregard photo of wire nuts.

P1060656 (Large).JPG
 
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I have never seen one with a hole in the bottom. I assume you grind it flat and the drilling is to remove the metal and create a hole to remove the top/bottom?

The only thing I grind flat are the two soldered wires which 'might' protrude through the side of the switch that goes against the sled. I do not modify the switch. The two flat head mounting screws which are countersunk in the board can be epoxied in. The screws will not fall out because the wire nut partially covers them, so it's your choice. The switch can be removed for service by unscrewing the two nuts. No epoxy to deal with. The only area of the mounting board that gets ground is a small circular area surrounding the switch screw so the epoxy will hold the wire nut. It is a very strong joint and the wire nut can't get knocked off. What I really like is that the alignment of the switch with the avbay hole can be way off and I can always funnel into that tiny screw. I am going to start using the larger Additive Aerospace switches since they are larger and easier to work with, and th screw is bigger.
 
Ok stupid question. WHERE can if find the two wire connectors?! I want them in my ebays and would rather buy some in bulk to have on hand. I keep finding big auto 2 pin connectors. Nothing like you have pictured here. really want some with a lock tab.

Do yourself a favor and get them from Bill at Doghouse Rocketry. He's right there in Viriginia. Customer service is unbeatable. Lots of other cool products on his site, too. I use his wiring kits and charge wells exclusively.
 
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