Neat & Organised Electric Wiring

[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?

[cavegirl47]

I don't know very much about wiring. I wasn't really involved with the electronics on the robot last year...I wasn't really involved with the robot for that matter, but I am interested now that I'm taking an electronics course and am doing my very own wiring. I know someone else has probably already said this, but I saw it on our robot, and I think it helped a lot: PUT LABELS ON EVERYTHING. Just little sticker labels on the wires themselves and the places where they go. You can do color coding, numbering, names, etc.

That's about all the advice I can give, and again, I bet you already knew this. But I hope I was of some help if you didn't.

[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.

[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.

[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.

[bhweezer]

The most neat and well organized robot I saw last year in Atlanta was 968.

Here is a picture. It's not very good, but I'll try to find another one.
http://www.firstrobotics.net/04Galle...0968-1_jpg.htm

[aaronbr28040]

I second the labels and the use of zipties. The best piece of advice I can give you is to plan before you wire everything. Layout everything before you do anything permanent. If it does not look neet when you do the layout then it isnt going to be neat when you finish, unless you do a lot of work. With the labeling deal, label everything.....the pwm cables, the wires going to the motors, and any other electronics and label them on both ends. This makes it much easier to swap out a controller or replace a broken victor or spike. Neat wiring also allows for quicker repairs so taking time to ziptie, label, and layout everything pays off at competition when that victor goes out or a pwm cable gets pulled loose.
-Aaron

[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.

[Dick Linn]

Here's some good info about crimping: http://www.svconline.com/mag/avinsta...onnectors_not/

I agree with AL about not using too much solder, especially on smaller wire. You risk failure of the wire rather than the connection. If you can afford a good ratcheting crimper for the smaller wire sizes, you really don't need to solder. They are a bit pricey, though.

[Travis Covington]

I have got a few pictures if you are really interested.

I must also suggest the use of soldered vs crimped connections. During the 2000 season our robot (team 115) was almost completely useless to us for a full regional and almost half of nationals. We went through everything twice and three times over (or so we thougt). Finally, with the help of Joe Johnson at nationals, we narrowed it down to one crimp connector that was only contacting on one or two of the strands of wire causing the breakers to trip constantly.

The problems we had that year is the reason why I now swear by the most organized wiring possible. Even if it takes a few days (in our case) it is worth it. I understand that alot of teams dont finish until last minute, but it is something that can really make or break an otherwise flawless robot. The most important thing is to take your time and have a few people check over the work when you think it's finished. And of course, test it as much and often as possible to see if you notice anything strange. This goes for everything including wiring and electronics.



2001 Robot (team 115):


2004 Robot (team 968):

[sanddrag]

Travis, you are one very skilled individual. We may never have your wiring skills, but maybe you can enlighten us with where you get your supplies. The wire and connectors appear to be of very high quality. Also, what was your reasoning for using 4 gauge for the main power (and is that 8 gauge to the drive motor victors?).