Battery lugs

[smcmahon]

In the kit again this season, there were two different types of battery lugs: the silver compression ones, and the copper-looking solderless ones with the screws. We've used both over the years. The screw-fastened ones tend to lose the wire after a while, while the silver ones work a lot better for us, but I'm fairly certain we don't have a perfect crimp on them. The tool AndyMark sells to crimp them is about $200, and while I'd imagine there are cheaper ones out there, I'm not sure we can justify that with our current budget.

If your team is using something other than these two kit options, can you point me to them and let me know how they're working out for you? I'm interested in exploring alternatives this season.

[hobbes20xxx]

The silver compression lugs i believe you can solder on with enough heat, if you have a scrap wire around i would test that first though.

[akosin]

We use the silver ones, put them in a vice, and turn until the table starts lifting up! :D

[Bill_B]

Screw lugs in use here. Grip lug body with vise grip and use a full-blade in the screw's slot. Tighten monster tight and use thread-lock on threads only. Don't get any on wire stands or inside grip zone. Make sure there are no renegade wire strands sticking outside the lug body itself. Remember to put shrink wrap onto each wire before connecting to terminals, if you prefer that insulation method. I have used a couple of sleeves on occasion. Orient the screw lugs toward the center of the battery to minimize having them scrape stuff during their lives. Thread lock again on the little bolts and use wrenches on the hex headed screw that holds lugs on the battery terminals. Then a tight tape wind of at least four layers over the top. Anyone need pictures?

[CalTran]

We use the silver ones because one of our mentors has the proper crimper that supposed to be used with it. I cant remember the name off the top of my head (IIRC it's a TNB crimper).

[DonRotolo]

The silver compression lugs i believe you can solder on with enough heat, if you have a scrap wire around i would test that first though.Very bad idea, you cannot prevent solder from wicking up into the wire, and making it too Brittle.
We use the silver ones, put them in a vice, and turn until the table starts lifting up! :DMy goodness, even worse, since the crimp will definitely fail. Before that, you will have high resistance - use Ohms law to calculate the voltage drop of 0.10 Ohm at 100 Amps....

A proper crimp actually deforms the copper wire and makes the small wires lose all air space between them in that area. Lacking the correct crimping tool you can use the crimping section of these pliers (http://www.harborfreight.com/9-1-2-half-inch-heavy-duty-linemans-pliers-with-crimping-die-38395.html). The crimping section is found between the pivot point and the handle. We use a good smack with a hammer to make sure the lug is fully compressed

[Teamcodeorange]

I found THIS (http://www.amazon.com/gp/product/B000M7LFKK/ref=oh_details_o04_s00_i00) to work well.

[Garrett.d.w]

Today we tasked one of our mentors with converting all of our batteries from the screw on lugs to the crimp on ones. Because we don't have a crimping tool big enough to handle the wire, he tinned the wire and then soldered it to the lug.

As DonRotolo said in his post above, allowing the solder to wick up into the wire will make it brittle. To keep this from happening he used the lowest temperature that he could get away with and went light on the solder. Of all of the batteries that he performed this operation on, only one wire wicked up solder. That one was replaced to avoid any headaches later on in the season.

I would not attempt this on my own though. I'm decent with a soldering gun, but I would probably make the attachment too weak or allow the solder to wick up the wire.

[Mr V]

If you are going to use the compression terminals don't bother with a flat head screw driver you need a #2 Robertson to properly tighten them. Our Canadian teams are more likely to have one available but for those of use that are in the US you can find bits or a screw driver at an electrical supply place, one that deals in house wiring supplies and tools. For the past 10 or more years the screws in electrical panels and the circuit breakers that go in them use the same dual drive screw and professional electricians will not use anything but the square drive.

If you want to use the crimp on terminals then you really need the Brundy crimper or a hydraulic one if you want a long term reliable connection. They are not intended to be soldered they have a slot to verify that the wire is fully inserted which precludes proper soldering. Proper soldering of battery lugs requires the use of solder pellets that are sized to the cable and lug to provide the proper amount of flux and solder. Personally for the automotive battery cables I make I only do the solder style for a much better long term connection.

[Tristan Lall]

At one point, Home Depot sold a 24 in crimper with three fixed dies and a bolt cutter for about $40. Critically, one of the dies was the right size for the all-metal crimpable terminals for 6 AWG stranded wire (both ring and Anderson SB). It's the perfect tool for the job, and at that price, it's worth a visit to the tool area of your local 24-hour Home Depot right now.

However, last time I looked, they only had an inferior 18 in one, with fractional-inch-sized dies (which are not quite right), for about the same price. (It's listed as a swaging tool, such as for wire rope connectors.)

Fastenal has a version of the good one, for about $200. For an FRC team, it might not be a good investment at that price point. For more demanding applications, it's still a good deal, because it's ridiculously fast and apparently very reliable.

Also, whatever method you employ, pull hard on the connector and wire after you've finished assembling the cable. There is no shame in it failing now, during assembly; there's lots of shame in the wires falling out of your battery during a match.

[sanddrag]

We use the silver ones, put them in a vice, and turn until the table starts lifting up! :DWe have had great results with the Harbor Freight 66150 Hydraulic Crimper (http://www.harborfreight.com/hydraulic-wire-crimping-tool-66150.html) which is currently on sale for $50.

[hobbes20xxx]

I found THIS to work well.

...I want one of those now!

[slijin]

If you are going to use the compression terminals don't bother with a flat head screw driver you need a #2 Robertson to properly tighten them.

This. If you use the supplied screws, it's near impossible to get the appropriate torque on those screws with a flat head. We use alternative products from Burndy (http://www.burndy.com/products/product-by-category/mechanical/mechanical-copper.aspx) (both the offset tongue and straight lug) because those are designed for flat heads, not Robertsons. I don't remember the exact specs on the types we have, but the ones we have accomodate 6AWG wire and a #10 stud (we use #10 hex hardware to secure the lugs against the battery terminals).

[DonRotolo]

I found THIS (http://www.amazon.com/gp/product/B000M7LFKK/ref=oh_details_o04_s00_i00) to work well.
I have seen them for well under $10 online.

and at that price, it's worth a visit to the tool area of your local 24-hour Home Depot right now.Teams will find these by the chain and wire rope display. Loews also sells them.

[sanddrag]

This. If you use the supplied screws, it's near impossible to get the appropriate torque on those screws with a flat head. If you use a Husky (or any other brand for that matter) flat head with a square shaft (or bolstered shaft) you can put a wrench on it.

[DonRotolo]

Cranking these screw lugs down as tight as you can is why they are loosening. Burndy recommends (http://ecat.burndy.com/Comergent/en/US/adirect/burndy?cmd=catProductDetail&showAddButton=true&productID=KPA4CUNPL&_bcs_=-1%08%23%23%08%23%23%08http%3A%2F%2Fecat.burndy.com %3A80%2FComergent%2Fen%2FUS%2Fadirect%2Fburndy%3Fc md%3DcatLanding%08%23%23%08true%08%070%08602382%2F 603178%2F603215%2F603218%2F603261*%08Straight+Lug+ Terminal%08http%3A%2F%2Fecat.burndy.com%3A80%2FCom ergent%2Fen%2FUS%2Fadirect%2Fburndy%3Fcmd%3DcatDis playStyle%26DispStyle%3DSingleLevelCategory%26catK ey%3D603261%08%23%23%08false%08) a tightening torque of 45 inch-pounds.

Over-tightening 'springs' the housing, encouraging it to deform and let the wire go.

A little purple loctite doesn't hurt though

[nuttle]

This looks like a nice solution: <http://www.crosstheroadelectronics.com/Battery_Cable.html>.

[smcmahon]

That DOES look nice. Potentially more flexible, and a bit cheaper than AndyMark. I think we'll order one or two for testing. Thanks Allen! Good luck this season.

[Al Skierkiewicz]

Two things. WildStang uses the crimp on connectors and while lacking a tool, a vise is an alternative. Place the connector in the corner of the jaw at a 45 degree angle with only about half of the connector in the jaw. Compress enough to hold the wire in place. Remove the connecter and then rotate 180 degrees and repeat. The result is a compressed terminal that show a nice "X". We follow that with solder to insure low resistance. As pointed out, only a minimum of solder. Add the solder from the mounting side of the connector and watch for solder at the wire end. You see no solder flowing if you do this right.
As to the screw type terminals, the greatest failing is too little stripped wire. These terminals work best when enough wire is protruding from the mounting side of the connector. When the screw is tightened, the wire should be a larger diameter outside the connector on both sides of the crimping body. Installers trying to make a nice looking terminal will not push the wire through the terminal and when tightened wire will eventually be pushed out the back of terminal like a banana from a peel.

[Lightfoot26]

Two things. WildStang uses the crimp on connectors and while lacking a tool, a vise is an alternative. Place the connector in the corner of the jaw at a 45 degree angle with only about half of the connector in the jaw. Compress enough to hold the wire in place. Remove the connecter and then rotate 180 degrees and repeat. The result is a compressed terminal that show a nice "X". We follow that with solder to insure low resistance. As pointed out, only a minimum of solder. Add the solder from the mounting side of the connector and watch for solder at the wire end. You see no solder flowing if you do this right.
As to the screw type terminals, the greatest failing is too little stripped wire. These terminals work best when enough wire is protruding from the mounting side of the connector. When the screw is tightened, the wire should be a larger diameter outside the connector on both sides of the crimping body. Installers trying to make a nice looking terminal will not push the wire through the terminal and when tightened wire will eventually be pushed out the back of terminal like a banana from a peel.

Quick Question Al, how does 111 go about insulating these connections? I like Heat shrink, but it gets tricky with a 90 degree connection!

[Al Skierkiewicz]

A long time ago, a very nice local supplier offered to give us some samples of silk screened heatshrink with our name on them. They ended up giving us like 50 of each color 3/4" x 3". We bend the flat part of the terminal, terminate the wire and then add the heatshrink over the wire end. Once terminated on the battery, we then slip the heatshrink over everything and shrink it. No metal shows with this method.
As I have posted a number of times before, a #10 external tooth lockwasher between the battery terminal and the wire terminal prevents the terminals from slipping and therefore prevents the hardware from loosening. We still have batteries from 2006 (practice only) that have tight terminations using this method. Internal tooth will likely work as well, but I like the added surface area and greater bite provided by the external tooth. A loose connection translates into high resistance and high temperature while also providing a nice intermittent to reset the Crio or radio..

[Richard Wallace]

Great advice from several posters in this thread, especially Don and Al.

I have used several methods to crimp terminals on 6 AWG wire for FRC robots. Most recently, I have been using this ratcheting crimp tool (http://www.mcmelectronics.com/product/PRO'SKIT-8PK-CT015-016-/22-7686) from MCM. I like it because it gives a secure crimp, and fits in my tool box.

After crimping, I like to sleeve the finished crimp using 3/16" heat shrink tubing, McMaster p/n 7132K75 (black) or 7132K752 (red).

[JDL]

This is the mechanical lug they are giving in the kit now. This is a terrible choice for a fine stranded conductor like they are giving us now.

http://ecat.burndy.com/Comergent//burndy/images/KPA4CUP_Photo_ColorCMYK.jpg

In my day job I've replaced a lot of them that were used on fine stranded conductors like in SO cord and DLO cable (diesel locomotive cable) because the screw either did't catch a lot of the strands or cut through them.

We used to get this style in the kit.

http://images.drillspot.com/pimages/9352/935292_300.jpg

Much better choice on a fine stranded conductor. The V grooved bottom and pressure plate equal a much better connection.

The crimps are the best way to go. In a pinch if you don't have a proper crimper or vise you can crimp the code connectors they give us with a pair of lineman's pliers with a crimp die behind the pivot point, if you are strong enough that is, not the way you want to do a lot of crimps either cause your hand is going to hurt after. ::ouch::

If you are going to solder after try your hardest not to let solder work its way to far up the conductor past the lug at after repeated bending it could break there.

[Al Skierkiewicz]

This is the mechanical lug they are giving in the kit now. This is a terrible choice for a fine stranded conductor like they are giving us now.
In my day job I've replaced a lot of them that were used on fine stranded conductors like in SO cord and DLO cable (diesel locomotive cable) because the screw either did't catch a lot of the strands or cut through them.


If you intend to use these, your local Home Depot or hardware store may have copper sleeves that can be lipped over the wire to make a better termination. When First forced us to use these in the past, we soldered them after termination and then insulated, of course. As JDL hinted, these are not designed nor intended for fine stranded wire.