I may have answered my own question.

Rule #1 search to see if your question has already been answered. I think the answer was posted by Jeff Shultz last year. IDC 905. Anyone see why that wouldn't work?

Oughta work

Based on the product description on Amazon, it ought to work. You might want to buy a small package at your local Ace or similar shop to test with to confirm it.

I use the 905s

I use the 905s as well with my 12 gauge main bus and 18 gauge feeders.

I actually pre-slice the insulation with a single-edged razor blade before I put the 905s on and they go on great over the cut, and the 18 gauge feeders go great in the feed side of the connector.

I've never had one of these IDC connectors fail in 26 years on my Siskiyou Line.

Before you order 905s...

You can't normally disconnect an IDC. I've decided on my layout to use Scotchlok T-Tap connectors. These crimp on the bus, but provide a means of easily disconnecting the drop wire which uses a crimp on spade connector. I'm thinking this approach will be a big help if and when I wind up wit one of those mystery short situations.

Search for 3M 952X for the 14 awg tap. I've misplace the P/N for the spade connectors. They're available from NCE as Track Bus Taps and Male Quick Disconnects. They were used in the TMTV TOMA Wiring episode 5.

Jerry

You can get those locally to

You can get those locally to you (and me) https://www.princessauto.com/en/detail/25-pc-16-14-gauge-t-tap-wire-connectors/A-p8238370e

Scotchlok T-Tap connectors

To use the Scotchlok T-Tap connectors you will also need male quick connects. Besides the advantage that you can disconnect the joint for trouble shooting, you can get male quick connects which will correctly allow crimping on wires from 22-18 (red), 16-14 (blue) and 12-10 (yellow).

  plus

Molex makes a similar series of products covering the same wire ranges ( 19216-0011, 19216-0010, 19216-0009). Again you will need mating male quick disconnects.

I second the T-taps,   If you

I second the T-taps,

If you accidently hook the wrong wire up to the buss it is easy to correct.  With the scotch loks you have to take it apart.  Not that I have ever done that, but........

from this point on it will only be T-Taps for me.

John

I "Third" the T-Taps

I switched to using T Taps on this layout and it sure makes troubleshooting much easier.

Another 'variant" is to use the IDC tap off the main bus, and run the tap to a terminal strip, one side of which is jumpered across all terminals, and then connect your individual track feeders to the individual terminals.  Again, makes troubleshooting much, much easier.

Al Carter

Sigh.

The T-Taps do indeed look like a great idea. I wish I had known about them before my father-in-law wired up his entire layout with 905's a couple months ago.

Such is life.

However, the product which frankly interests me even more is this one:

https://www.amazon.com/Connector-LOUFIMIDON-PCT-213-Conductor-Terminal/dp/B06XSXPVKX/ref=pd_sbs_60_4

Has anyone tried them yet?

Wago terminals

I've bought a load of the newer WAGO type for rebuilding of my layout. The newer 221 versions ones are far easier to lift the clamp. Rated lower than the 222s but 20A should be enough for anyone. I have three way for tapping into a bus lines and five way for where I need more connections.

https://www.amazon.com/Wago-221-413-LEVER-NUTS-Conductor-Connectors/dp/B017NQWDY4/ref=pd_sim_60_5?_encoding=UTF8&pd_rd_i=B017NQWDY4&pd_rd_r=1YDKQ9RPWAV9D8E7Z4R5&pd_rd_w=uZHiC&pd_rd_wg=zcEnH&psc=1&refRID=1YDKQ9RPWAV9D8E7Z4R5

I've used IDC's before with no problems, but Wagos are easy to disconnect when fault finding, and you can mix a wide range of cable sizes. Apart from a wire cutter/stripper no other tools are required.

Mike Ruby

Lever-Nuts

Are great.  But it's counterproductive to cut your main bus everywhere you want to tap in a feeder (introduces two more connections each time, think increased resistance), so Scotchloks or T-taps still have a place.

I'm using all three - plus, a bunch of wire nuts we resorted to when we ran out of scotchloks one day.  Whatever gets the job done.

Blair

Interesting

Joe, according to 3M's site 905s are for 18-14 run 22-18 tap.  Do you find it hard to close on the 12 gauge? is that why you pre-slice the bus?

I use the 567s for my 12 gauge bus and 18 gauge feeders.  I also use the special tool for crimping them.  One of the things I like about the 567s is that they are a double blade.  I think it might give a better connection.

Paul

I prefer the 567's over the 905's

I've been helping a local modeler with wiring on his layout and he uses the 567's to tap into his main bus (14 gauge).  Because the 567's are double-blade, it's fairly easy to use a small screwdriver to pry up the blade from the wires.  While reworking most of the yard, I was able to pop off and reuse all of the 567's originally used.

Because the 905's are single blade, there's no easy way to get a grip on the blade to pry it up/out/off, so any rework results in a bunch of old IDCs  cluttering the bus.

Craig

contact resistance

I looked on line but was unable to find  any info on typical contact resistance, may be a factor in breaking the bus at each drop connection, but the easy disconnection for isolating problems is appealing 

My preference

Is for long-term electrical reliability, so adding two joints for every feeder is just not on my horizon.  How often have you seen a short develop, once the initial wiring has been done successfully?  By colour coding my feeders, I can see at a glance if we've crossed any as we go.  When wiring, we try to power the rails periodically, just in case, but we rarely induce a short.  Other than that, it's down to track shorts, and there aren't many of those(crosses fingers).

As for resistance, for my bus runs of 80', I really care that I have a continuous buss wire.  Chopping it into 3' sections makes no sense.  It's challenge enough to keep the quarter test running, without introducing more resistance.

YMMV, as always.

Blair

Connections

I don't know why people are so against connections. Part of my job is wiring machines where we have 400v / 24v running from mA up to several 100 amps running through many terminals and plug/sockets in line. These machines run up to 24hrs per day, 6 days a week. Connection failure, unless damaged from external influence, is extremely rare. Switches, relays yes, but not connections.

I can't think of a single time when one of my layouts has had a connection failure. So long as you make connections correctly i.e. correct sized wire in IDC, correct tool for crimps, not nicking the core when stripping, doing them up tight enough (one advantage of the spring clamp type, they don't come loose) and clean solder joints, there is no reason worry.

Mike Ruby

Skillsets

Mike

While I agree on one level (I'm an electronics tech), I recognize that others aren't as comfortable with the trade.

Not everyone is an electrician, or good at everything they do.  You've outlined exactly why you've had success.  People's layouts aren't generally built with the robust requirements of machinery on the factory floor, nor are the people building them skilled in all the trades required.

YMMV, respectfully.  

Blair

Not a T-Tap Fan

On my club's layout, on an operating day (~20 operators), we lost the entire east end of our main yard ladder track (Lebanon yard for those that know it) due to a T-Tap working loose on a main bus line. It was behind the facia, a fair distance from the track, and took a while to find. We had to remove the facia to find it, which has many screws and in this area a concrete slab under the deck. It created quite a problem. We don't know how it worked loose, but it did. There are very few connections of this sort on the club layout for this reason, it is just too risky to have a disconnection where it is not easily serviced. I removed that T-Tap and put a Scotchlok 567 in it's place, I am not going to let that happen again.

We use the Scotchlok's everywhere (mostly 567's) and have not had any problems, I personally like them. Isolating a block is done at the circuit protection if needed (bulb or electronic, we have both) by removing it's feed. That is very, very rare to have to do that. 

If a short appears in a track block, from debris or something, I use a DMV and walk the voltage drop down to get near the short. Then I can usually see where it could be (some usual suspects) or feel the heat from a short. On our layout, the most common short is some piece of conductive material getting in the isolation cuts in the PC ties used for turnouts. We need to put something on those to keep stuff out. Different topic... 

I know the T-Taps feel like a safety net, in case you have problems, but my humble opinion is they may actually cause you more problems. That said, I am sure lots of people use them and have not been bitten. So, this is just a counter point. YMMV...

Erik

Not a T-Tap fan

I have known the female parts of that type of connector loosen up in other uses, especially on higher currents. I suspect it is because they are not made from a springy material and they slowly deform, although they work in motoring uses for many years. It maybe the quality of the parts.

If using them I always make sure they are a tight fit, if not I squeeze them slightly before making the connection.

With regard to skill, most of the things I mentioned are fairly simple so long as you are aware of them, which is why I listed the basics. Soldering is the one where some knowledge and practise is needed. I'm still trying to stop local modellers using acid flux, it works ok, but in a few years when the remaining acid has attacked the joint...

Mike

I Don't Cares (IDCs)

Solder is cheap and quickly reversible. 'nough said.

Nick