Skip to main content

A couple of years ago I was modifying a pair Lionel NYC Alco PA-1 both powered.  I wanted to use the electronics from one unit in an early Williams FM Trainmaster since it had Pittman motors and MagnaTraction.  I had to modify the heatsink for the DCDR motor driver and open a path on the rear truck for the eight wire harness to exit and pass over the couplers to connect the two units.  I used connectors called Dupont connectors which I ordered on eBay. They come with single pin male and female connectors on the end of multi strand ribbon cable which you pull off as many strands as you need. My method is to pull off two strands each with half as many conductors as I need and glue the two strands together at the connectors with thin CA. Note that I kept the open side of the connectors all on the outside so glue did not flow inside should I need to remove the conductor inside. Also note that I staggered the connectors to make the plug polarized so it can only plug together one way.  The first five photos show how to assembled the harness the others show the modifications to the rear truck of the  Alco PA-1s  to facilitate routing the two halves of the harness out the rear of the locos. Something I like about the ends of the Dupont connectors is how easy it is to pull the conductors out of the plastic grip. This made it easy to swap 22 gauge wire for the power and chassis ground conductors between the units. I used silicone insulated wire for these conductors for two reasons. It has a very fine multi-strand wire inside that together with the silicone insulation makes it extremely flexible. It is also much less likely than vinyl to melt in the event of a short.  Next time I make one of these I plan to substitute silicone wire for all the conductors. Come to think of it I wish I could just buy the ends.   j

 

107B1942_01

Attachments

Images (15)
  • 107B1942_01
  • 107B1952
  • 107B1962
  • 107B1972
  • 107B1982
  • 107B1992x
  • 107B2012
  • 107B2032x
  • 107B2072
  • 107B1852
  • 107B1872
  • 107B1901
  • 107B1931
  • 107B2042
  • 107B2121
Original Post

Replies sorted oldest to newest

After posting this I searched ebay and found that you can indeed buy a kit now with seperate ends and they are available in multiple conductors.  This would make the process much easier.  These were not available two years ago though I guess I could have missed them.  I did search the entire category.  Link below is for a kit with connectors with  1, 2, 3, 4, 5, & 6 pin connectors,  There are kits with up to 12 pin connectors. You may want to search the category  "Dupont Connectors" for a better idea of whats available.                              j

https://www.ebay.com/itm/620pc...8:g:IbMAAOSweZJaJm-O

DUPONT CONNECTORS

Attachments

Images (1)
  • DUPONT CONNECTORS
Last edited by JohnActon

I got lost on one point, but assume you mean you doubled up 22g  to each terminal...?  (mind terminals have max amp ratings too. The spec is in the max wire gauge listed. E.g. For 18-14g handles 14g worth of power.

Also, power delivery wire has a lower awg max amps than signal wires (that usually get a break from work via frequency, or power reductions which form signals.)

Dupont makes all kinds of good stuff.

Why not use the standard connectors used by Lionel for all their TMCC stuff?  They use JST-EH (2.5mm) and JST-PH (2.0mm) for most TMCC stuff, once in a while you'll find the smaller JST-ZH (1.5mm) connectors.  Legacy mostly uses JST-ZH and Molex PicoBlade (1.25mm), though there is still some JST-PH connectors in some models.

You can get all of this stuff from Digikey, and I use the Engineer PA-09 or IWS-2820M AWG 28-20 crimp tool, both available on Amazon.

Adriatic posted:

I got lost on one point, but assume you mean you doubled up 22g  to each terminal...?  (mind terminals have max amp ratings too. The spec is in the max wire gauge listed. E.g. For 18-14g handles 14g worth of power.

Also, power delivery wire has a lower awg max amps than signal wires (that usually get a break from work via frequency, or power reductions which form signals.)

Dupont makes all kinds of good stuff.

Did not double up any single conductor I did substitute 22g on two connectors one for power and one for chassis ground. I think I also put 22g on the motor leads ?      All the other wires were the stock 28~30g. Can't imagine ever needing 14awg for a harness between to O gauge locos.  I think what threw you off was the part where I pulled off two strands of four then reversed the ends so there is a M & F connector on each end once they are glued together. I staggared them when gluing together it helps keep them from giggling apart from up / down and side to side forces. The combination of M & F connectors on each end "Polarizes them" to prevent  plugging in backwards.  I don't plan to make my own harness on each TMCC conversion but all my plugs  MTH and Lionel were 90 degree plugs and I wanted the straight through connection on the PA set. The 4,  545 size motors will pull stumps. I have ten 20" Weaver cars and they drag them around without effort. The DCDR motor driver that came in the Alco PA does not have cruise but the AA pair has so much power it hardly slows on grades so I don't miss not having cruise.   Enlarge and look closely at the pix they tell the story far better than I can type it.  Typing is one of my least favorite things to do.       J

gunrunnerjohn posted:

Why not use the standard connectors used by Lionel for all their TMCC stuff?  They use JST-EH (2.5mm) and JST-PH (2.0mm) for most TMCC stuff, once in a while you'll find the smaller JST-ZH (1.5mm) connectors.  Legacy mostly uses JST-ZH and Molex PicoBlade (1.25mm), though there is still some JST-PH connectors in some models.

You can get all of this stuff from Digikey, and I use the Engineer PA-09 or IWS-2820M AWG 28-20 crimp tool, both available on Amazon.

John,  I put JST plugs on the end of the harness inside the loco at the boards. I bought 1000 pins and 100 each 2,  3,  4 & 5 conductor plugs when I first started converting my conventional loco collection.  I have been buying used boards both TMCC and PS2 and 3 usually they come with a bunch of plugs if not a complete harness so I haven't had to make any 2 or 3 pin plugs but have made some 4 and 5 pin. I don't have a crimp tool however and have been soldering the pins on. Since I don't do work for others I am not bound by many of the constraints that you are.  When I made these plugs I did not want to cut holes in the bodies and did not have a proper Lionel or MTH plug on hand. All I had were 90 degree and I wanted to go straight across the top of the couplers. It turned out neat and functional and to be truthful I get a kick out of non conventional solutions.  I took the year off so far from twisting and soldering wires to do some painting and build an interior for a MTH diner that had no interior. I was about to post some shots of the diner interior when someone posted a drop dead gorgeous UP dome diner.  Made me want to plug in the soldering iron and breath some resin core fumes.  Much less painfull than painting 48th scale patrons for my diner.          j

103_7480          

Attachments

Images (1)
  • 103_7480
Last edited by JohnActon

   I can't use the viewer here & that pic is too small or to low a resolution. No biggie. 22g strikes me as lite for power delivlivery; that'st allhat. It's about 4a max for power delivery, but I guess maybe with chopped waves your running cooler anyhow.

. I get "polarized", we always said "keyed". I took to slices for keyways on the male end and cutting bands on the females melt/benting my own keys once.

I like to use plugs with the ability to add a female pin among males and visa versa for a one fit only mating. I bought large and left blanks to match up too.(ind.machines/coin-op/hvac/offroad) 

  I think I've dealt with those in printers. You know how hard it can be to say for sure out of hand. 

I like a dual sae crimp that holds the insulation. The ''crushed heart"♥️, that splits the strands into 2 bundles,  and a dot of solder just in case. "A-A nunchucks" lol. 

Adriatic posted:

   I can't use the viewer here & that pic is too small or to low a resolution. No biggie. 22g strikes me as lite for power delivlivery; that'st allhat. It's about 4a max for power delivery, but I guess maybe with chopped waves your running cooler anyhow.

FWIW, virtually all of the Lionel and MTH stuff uses #22 wire for the power connections.

Footnote:  Lionel harnesses use 105-degree insulation (Centigrade, IIRC).  Yes, I know that's the old name; try Celcius, which the site tells me I have misspelled, or... .  Most of your amperage/wire gage tables will be based on some other temperature rating.  Then your ambient temperature is a factor-- few have belonged to a club in a 105-degree (Fahrenheit) space.  Some useful relationships for the logarithmic AWG series:

3 gage numbers lower will double the copper area, but 4 gage numbers (as 26 AWG to 22) will be required to double the amps carried (or ampacity) without raising the copper temperature in contact with the insulation provided that the insulation thickness  does not increase.   Get manufacturer's tables if possible. --Frank

  

Add Reply

Post

OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
800-980-OGRR (6477)
www.ogaugerr.com

×
×
×
×
Link copied to your clipboard.
×
×