Neat & Organised Electric Wiring

[Ken Patton]

Some good guidelines here, but I have a few questions for you guru's:

1. Why do you say to use velcro instead of zipties? Seems to me there would be less stress on the wire bundle to just snip off a ziptie than there would be to try and rip the velcro.

2. What brands of super-flexible wire are you using? (I know Paul Copioli and 217 have used this stuff on their well-organized wiring jobs - they are my benchmark for great wiring).

3. Aren't you supposed to solder the end BEFORE crimping? This is called tinning I believe.

One idea that we have used the last few years: rather than hard mount the polycarbonate control-mounting-board to the robot, we have "suspended" it trampoline style from the frame. Seems to me that this is lighter and it provides some amount of isolation from the vibration of the robot.

Ken

[petek]

Originally Posted by Ken Patton

3. Aren't you supposed to solder the end BEFORE crimping? This is called tinning I believe.

No! You should never tin wires before crimping because you won't get good pressure distribution inside the crimp and it will loosen over time. If you use good quality crimp connectors, sized exactly for the wire gauge, crimped with the right tooling, the connection will be as good as it gets (without soldering). Because there are so many "ifs" in that, soldering after crimping is recommended for most other cases!

[JVN]

Here are some of the boards we're looking at for inspiration in 2005:

258's 2003 board is pretty cool.
http://www.seadawgs.com/Pictures/200...d/Img_0820.jpg
http://www.seadawgs.com/Pictures/200...d/Img_0821.jpg

Note the way the RC mounts over the Spikes (which require no ventilation)... slick!



Also 968's 2004 board. (That entire robot is a work of ART. So neat, so organized. I wish we could be like this!):
http://www.chiefdelphi.com/forums/sh...ad.php?t=25672
I wish I had more pics of that one.


And... my favorite, Team 71's control board:
http://www.team229.org/photo/single/2441
http://www.chiefdelphi.com/forums/pictures.php?s=&action=single&picid=7159&direction =DESC&sort=date&perrow=5&trows=10&quiet=Verbose
You can't really see it in these pictures but...
Basically they're entire control board is mounted on thin lexan. They then suspend this sheet from their robot frame. (As an outside wall of the robot).
I wish I had a good picture of their 2004 board. It makes me feel like our control board is waaaaay overweight...

Though, knowing our luck...
If we tried the Beatty method -- another robot would probably stick their arm through it or something every match.

[Bill Gold]

Originally Posted by JVN

Here are some of the boards we're looking at for inspiration in 2005:

258's 2003 board is pretty cool.
http://www.seadawgs.com/Pictures/200...d/Img_0820.jpg
http://www.seadawgs.com/Pictures/200...d/Img_0821.jpg

Note the way the RC mounts over the Spikes (which require no ventilation)... slick!



Also 968's 2004 board. (That entire robot is a work of ART. So neat, so organized. I wish we could be like this!):
http://www.chiefdelphi.com/forums/sh...ad.php?t=25672
I wish I had more pics of that one.


And... my favorite, Team 71's control board:
http://www.team229.org/photo/single/2441
http://www.chiefdelphi.com/forums/pictures.php?s=&action=single&picid=7159&direction =DESC&sort=date&perrow=5&trows=10&quiet=Verbose
You can't really see it in these pictures but...
Basically they're entire control board is mounted on thin lexan. They then suspend this sheet from their robot frame. (As an outside wall of the robot).
I wish I had a good picture of their 2004 board. It makes me feel like our control board is waaaaay overweight...

Though, knowing our luck...
If we tried the Beatty method -- another robot would probably stick their arm through it or something every match.

When I saw the title of this thread the last thing I expected was for one of my robots to be mentioned, much less alongside the likes of the mighty Travis Covington's superior wiring techniques. Thankfully John was just brining up a little trick we used that year, and other teams have done as well. Seriously, Travis’ wiring always drops my jaw. It’s something that we all should aspire to wire like.

[Al Skierkiewicz]

Originally Posted by Ken Patton

Some good guidelines here, but I have a few questions for you guru's:

1. Why do you say to use velcro instead of zipties? Seems to me there would be less stress on the wire bundle to just snip off a ziptie than there would be to try and rip the velcro.

2. What brands of super-flexible wire are you using? (I know Paul Copioli and 217 have used this stuff on their well-organized wiring jobs - they are my benchmark for great wiring).

3. Aren't you supposed to solder the end BEFORE crimping? This is called tinning I believe.

One idea that we have used the last few years: rather than hard mount the polycarbonate control-mounting-board to the robot, we have "suspended" it trampoline style from the frame. Seems to me that this is lighter and it provides some amount of isolation from the vibration of the robot.

Ken

Ken,
There are several companies that make velcro just for wire management. I think it is OK for static loads but I question it's use on movable objects like our robots. The load on a large wire bundle during a hit is likely to open.
Newark sells a #10 zip cord that is not super flex but is more flexible than most off the shelf #10. It is designed for automotive stereo install and has a red and black wire.
A great connection is one that is mechanically stable first. Any connection that will be soldered should be crimped tight first. We use a equivalent to the Anderson connector for #10 connections (to make it easy to change) to motors. We add push on 1/4" connectors for speed controllers. (The same as are on the circuit breaker panels.) All of these connectors start out as uninsulated. We crimp the wire then solder and add a piece of heatshrink over the wire and connector to protect it, the contacts for the Andersons must not have exposed wire after contact insertion. Never "tin" wires before a crimp contact as explained above.
Adding a poly plate to mount everything just adds too much weight for us. I am under STRICT guidelines for weight restrictions. (wink, wink)

[Sparks333]

Hi!
I really can't talk too much (our robot's wiring job was TERRIBLE!!!) but here's some good ideas.

1) Use plugs. If you use, say, a Molex connector, then if you have to pull a component or even an entire board, you just disconnect it. My team is after me to modularize the entire electronics board, so this seems like a reasonable idea. It is, however, one more thing to go wrong.

2) SOLDER WHENEVER POSSIBLE!!!! I really don't care if you have crimp fetishes or only have crimps or if you have already crimped a wire. Crimps fail much more often than solder jobs. (Last year for our main connector to the battery, we used crimps tightened down in a vice, then we heated it with a blowtorch and put lots of solder on it. Worked like a charm, and looked cool too.)

3) Never, and I mean never, put a wire under stress and expect it not to come out. If you have a 12" gap and an 11" wire, then go get yourself a 13" wire, dangit! Vibrations can wear through wires, pinch sections can cut wires, and tension can pull your connectors right out. USE A LONGER WIRE THAN WHAT SEEMS REASONABLE! it may weigh more, but it will work.

Neatness and orgainization is a very valuable thing to have on a robot. It streamlines repairs, diagnostics, and makes the robot look good. And your team will love you for it.

Sparks

[Al Skierkiewicz]

Originally Posted by Sparks333

2) SOLDER WHENEVER POSSIBLE!!!! I really don't care if you have crimp fetishes or only have crimps or if you have already crimped a wire. Crimps fail much more often than solder jobs. (Last year for our main connector to the battery, we used crimps tightened down in a vice, then we heated it with a blowtorch and put lots of solder on it. Worked like a charm, and looked cool too.)

I agree that soldering is a solution to prevent failed connections. I do want to say that there is a way to add too much solder when making connections. Stranded wire will wick solder (just like water soaks into a paper towel) and that extra will end up far from the joint. For most applications this is not a problem, but this wire now becomes very stiff, almost like solid wire. A solid wire on a moving object has a greater tendency to fracture after repeated movement. When soldering connectors (to the 1/4" push on crimp type, for example) heat the connector until solder flows when applied to both the wire and the connector. Add just enough solder for it to be just visible flowing under the wire insulation. After the joint cools, the wire should still be flexible almost to the end of the wire. This is especially important for connections to the controllers, battery and FP motors. A stiff wire will transmit movement into the terminals and cause internal damage over time.
Don't forget adequate insulation over the soldered joint, heatshrink works better than tape and more fun to use.

[Sparks333]

Originally Posted by Al Skierkiewicz

Don't forget adequate insulation over the soldered joint, heatshrink works better than tape and more fun to use.

Al,
I agree with you there. I have often had only tape around, and used it, then regretted it. It sticks to whatever you are using to get it off, leaving a sticky black residue, and it's not easy to get a good grip on and unwind. Heatshrink, because it's not sticky, doesn't have these problems, but be sure you heat the heatshrink slowly and evenly. I have a friend that simply stuck it on a soldering iron, and it melted right through the heatshrink (counterproductive, if you ask me.) Just remember to cut it and put it pretty far down the wire before you solder the connection, as you won't have a chance later.
My 2 cents.

Sparks

[Elgin Clock]

I figured I would throw this in this thread rather than starting a new one seeing as I have the attention already of the electrical guru's of FIRST.

How do you feel about heat shrink, or cold shrink tubing?

What are the advantages/ disadvantages of each compared to each other? (heat shrink vs. cold shrink)

When should it be used?

Should it be used instead of electrical tape?

How easy is it to fix if something goes wrong underneath the tubing as opposed to electrical tape?

[Al Skierkiewicz]

Originally Posted by Elgin Clock

What are the advantages/ disadvantages of each compared to each other? (heat shrink vs. cold shrink)

When should it be used?

Should it be used instead of electrical tape?

How easy is it to fix if something goes wrong underneath the tubing as opposed to electrical tape?

Elgin,
I am not sure what product you are referring to as "cold shrink".
I use a variety of products depending on the application. Heatshrink is the easiest to cut, shape, etc. and makes a nice finish look. When the need arises for a repair justs take a sharp blade and cut down the length of the covering. If you need a higher voltage breakdown just add a second or third piece over the top. It is not waterproof, though, even the meltable interiors tend to leak a little when out in the weather. There is a good product called COAXSEAL, available from many locations including Radio Shack. It makes a good waterproof, ultraviolet resistive, flexible seal but is nasty stuff to work with.
Since waterproof is not a requirement for our robots, yet, heatshrink is easy for everyone to use and electrical tape a close second.

[Elgin Clock]

Originally Posted by Al Skierkiewicz

Elgin,
I am not sure what product you are referring to as "cold shrink".

See, It's true what they say. You do learn something new every day.

That aside, I had never heard about cold shrink tubing before about 2 years ago either. We used it where I worked, making coaxial and other RF cables, and it is just another alternative to heat shrink tubing.

Thanks for the link btw, Sparks.

[Al Skierkiewicz]

Originally Posted by Elgin Clock

See, It's true what they say. You do learn something new every day.

That aside, I had never heard about cold shrink tubing before about 2 years ago either. We used it where I worked, making coaxial and other RF cables, and it is just another alternative to heat shrink tubing.

Thanks for the link btw, Sparks.

Elgin,
If this is the product you are asking about, the 3M series. I was not able to find anything smaller than #6. It is manufactured for the power industry and then only a small part. (At least I have not seen any inside wiring using it.) It is a good example of designing for your customer. An outside wireman might not always have a torch or handheld heat gun available on the jobsite so cold shrink is a good alternative. They appear to be a little pricey for robot use, though.
I wanted to add that there is a company that I use in my job everyday, Brady Label. They make a variety of products but they ones I use allow you to write on, or type on a message. You then peel the label and wrap it around the wire. The lable has a clear area that overwraps the white writing area, protecting it and preventing it from being pulled off. They even sell a hanheld printer that will make the label for you. We have two at work.

[Sparks333]

Originally Posted by Elgin Clock

.

How do you feel about heat shrink, or cold shrink tubing?

What are the advantages/ disadvantages of each compared to each other? (heat shrink vs. cold shrink?

Elgin,
The difference is mostly preference, I think. A good article descibing pros and cons by a guy from 3M is here. Read it and make your decision.

Sparks

[dubious elise]

for labelling wires, use a dymo electronic label maker with plastic (not paper) labels. they last a very long time, are a snap to make, and are small enough to fit almost anywhere.

[Mike Betts]

Originally Posted by Sparks333

...
A good article descibing pros and cons by a guy from 3M is here. Read it and make your decision...

Sparks,

A very good article. Thank you.