Hey Richard, that's a pretty quixotic venture there buddy ...
KISS!!
12" of shooters wire - done.
1/4" ID 4x heatshrink
Only downside is you have to abort ( I use a peer of needlenose ESD
tweezers to fish the wire out of the venthole
and OMG it is a PITA).
On Thu, Jan 19, 2017 at 8:23 PM, R Dierking <applerocketry@xxxxxxxxxxx>
wrote:
I’ve given the twist wires some thought. Here are a couple reasons I
don’t like it.
- Seems you would have to keep the wires from being damaged during
transport and even potentially damaging the inside connections from pushing
and pulling. Even if there’s some protection from stress, if you handle
the wires at all, you are moving them inside and potentially weakening the
connection points.
- The wires are on the outside of the airframe. Probably not an issue
with drag, but could be damaged during the drogue deployment or when the
rocket hits the ground. Not a big deal if the main deployed, but what if
it didn’t.
- Recycling is a problem. If the wires were twisted adequately to
assure the connection, it might be difficult to make a clean
disconnection. I guess you could cut them, but might be a hassle providing
new bare wires. Particularly if there’s stress protection. If you twist
and untwist the wires, they will be weakened. OK, the people that seem to
be using this technique probably don’t have to recycle many rockets. Have
I ever seen Wedge have to put a new igniter in his rocket? LOL.
The bigger question: Why are some people using this technique? It is
simple, but perhaps it’s also because installing the group of switches we
commonly use is a hassle.
Mounting a reliable toggle switch is out. Slider switches, even if they
are installed on the inside of the airframe, are really bad for rocket use.
It’s difficult to install a switch on a sled and have it line up properly
with an access hole on the airframe. Installing panel mounted switches on
a curved airframe can be a pain. Particularly if it’s a smaller diameter
rocket. Barrel-type key switches work, but after awhile they get to be
dorky. And, the irregular holes take time to make. The “good” switches
don’t seem to come with a simple way to mount and use them. For example,
microswitches. They’re good switches, but making them work for our use can
be a project in itself.
If there was a reliable switch mechanism (like the Aerocon PCB switch),
mounted in a holder that you could attach/epoxy to the inside of the
airframe after you drilled a hole to access the switch, people would be
more inclined to use this than twisting the wires. You have to drill
multiple holes for the wires anyway. If the switch came with wires already
properly soldered, it would be pretty easy to install. The switch doesn’t
have to be a component on a bay sled. Some people don’t want it to be.
I would like to see a 3D printer design that would hold an Aerocon PCB
switch to the inside of an airframe tube. Keep in mind that if two sides
are the epoxy attachment points the switch would work for many different
sizes of tube. If the hole was smaller than the head of the activation
screw and it was close enough to the inside of the airframe, the screw
could not come completely out.
Richard Dierking
*From: *Chris Attebery <chrisattebery1971@xxxxxxxxx>
*Sent: *Thursday, January 19, 2017 6:57 PM
*To: *roc-chat <roc-chat@xxxxxxxxxxxxx>
*Subject: *[roc-chat] Re: Twisting Wires
Gerald,
If I ever use twist and tuck I'll use your method. Nice job.
Chris
On Thu, Jan 19, 2017 at 6:45 PM, James Dougherty <jafrado@xxxxxxxxx>
wrote:
Hey Gerald,
WHere's that picture you took at LDRS with the Marilyn and heat-shrink?
:-)
-james
On Thu, Jan 19, 2017 at 5:17 PM, gerald meux, JR. <
dmarc-noreply@xxxxxxxxxxxxx> wrote:
See post #55 on link below for visual form of one way of doing twist and
tuck.
http://www.rocketryforum.com/showthread.php?112713-How-many-
switches-on-a-dual-alt-recovery-system&p=1302474#post1302474
Thanks -
gerald meux, jr.
602-472-5869 <(602)%20472-5869>
kninja250r@xxxxxxxxx
-from mobile device-
On Jan 19, 2017, at 7:59 PM, R Dierking <applerocketry@xxxxxxxxxxx>
wrote:
Evidently twisting wires to activate electronics can work very well.
Gerald has done this on his high-performance projects. So it works with
high velocity and altitude.
I’m kidding a bit about the practice. But there’s a correct (safe and
reliable) way to set-up twisting wires. Not the twist part; the it’s the
way the wires are secured in the airframe and protecting them from shorting
or coming apart during the flight.
Richard
*From: *Wedge Oldham <wedgeoldham@xxxxxxxxx>
*Sent: *Thursday, January 19, 2017 4:26 PM
*To: *roc-chat@xxxxxxxxxxxxx
*Subject: *[roc-chat] Re: Twisting Wires
I twist my wires once. Then replace with new.
Sent from my iPhone
On Jan 19, 2017, at 1:31 PM, R Dierking <applerocketry@xxxxxxxxxxx>
wrote:
OMG, Chris Kobel is another twister. Well, it’s out there now thanks to
RickyLeaks. Like when I saw James D (one of the most technical savvy
people I know), twist the arming wires to his electronics and stick them in
a two stage rocket. I thought, OMG, my buddy is a bohemian.
So, perhaps shoe strings and belts would even been too complicated for
you guys. Yup, slip on shoes and elastic waist bands for you. ��
So twisting wires or switches…Can you twist and untwist two wires 300
times without a failure?
LOL
Richard
*From: *Chris J Kobel <chris.j.kobel@xxxxxxxx>
*Sent: *Thursday, January 19, 2017 1:13 PM
*To: *roc-chat@xxxxxxxxxxxxx
*Subject: *[roc-chat] Re: Twisting Wires
Full disclosure, I use switches on most of my dual deploy rockets. I
had one micro slide switch fail, thank goodness for independent, redundant
electronics. I’m twisting wires because I haven’t bothered (yet) to
replace the failed switch J
Chris
*From:* R Dierking [mailto:applerocketry@xxxxxxxxxxx
<applerocketry@xxxxxxxxxxx>]
*Sent:* Thursday, January 19, 2017 1:04 PM
*To:* Chris J Kobel <chris.j.kobel@xxxxxxxx>; roc-chat@xxxxxxxxxxxxx
*Subject:* RE: [roc-chat] Twisting Wires
I hate the twisting wire technique. Yet, some people that I look up to
actually do this. It’s just so barbarian. And, then they stick the wires
back in a hole in the airframe. Freakn crazy dude.
I imagine someone twisting some wires on a Falcon 9 before launch.
Hopefully they would read the technical manual on how to do it correctly.
If it was at JPL, they would have the technician twisting the wires while
two engineers watch. LOL
Richard Dierking
*From: *Chris J Kobel <chris.j.kobel@xxxxxxxx>
*Sent: *Thursday, January 19, 2017 12:48 PM
*To: *roc-chat@xxxxxxxxxxxxx
*Subject: *[roc-chat] Twisting Wires
More and more, this conversation is encouraging me to keep twisting my
wires together. Somebody mentioned it previously…is there a “right” way to
do it, to go along with all the wrongs ways I’ve tried?
(I do try to insulate the twisted wires and tie a piece of string on
them so I can fish them out of a breather hole to disconnect them after a
flight…)
Chris Kobel
*From:* roc-chat-bounce@xxxxxxxxxxxxx [mailto:roc-chat-bounce@freeli
sts.org <roc-chat-bounce@xxxxxxxxxxxxx>] *On Behalf Of *R Dierking
*Sent:* Thursday, January 19, 2017 12:40 PM
*To:* Kenneth Brown <ken@xxxxxxxxxxxxx>; roc-chat@xxxxxxxxxxxxx
*Subject:* [roc-chat] Re: Switch Warning - Schurter 110-220
Sorry if there was a misunderstanding Ken. I don’t routinely have the
soldering iron dwell on the contacts that long. Just trying to figure out
potential failure modes for this switch. The objective is to provide
information to people that have already used these switches in projects,
and maybe others that will use them in the future. Verses, “hey, don’t use
these switches.”
For example: If someone is planning on using one of these switches,
they could have good information about how to install them and solder the
contacts. Also, and I think this is very important, they should be advised
on how to check the installed switch for problems before flying their
project.
This helps not only for the case of using these switches, but for using
other electronics as well. Having detailed information on the device, and
testing before flying a project is always a good idea.
Richard Dierking
