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Using PCB connectors 2.54mm

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Using PCB connectors 2.54mm
Posted by ChrisVA on Saturday, June 26, 2021 5:45 AM

I got these PCB connectors on eBay with the idea I could use them to have a DCC decoder in my tender and use these to connect to the motor in the boiler. I've never used these before so I need some help.

https://photos.app.goo.gl/7yikHXqHecLEXZ4z5

Basic problem I'm trying to solve: use these to connect DCC decoder in tender to motor and headlight in boiler.

If I want to connect 4 wires from tender to boiler (2 for motor, 2 for headlight), how would I go about it? I'm assuming I would somehow cut 2 sets of 4 plugs from this strip.  How do I cut off 4 plugs? With an Atlas saw or something?

Then I solder 4 wires from the tender to the back of 4 of these connectors, use the plug to connec to the holes to the 4 connectors in the boiler, solder 4 wires on the ends in the boiler to my motor and headlight?

New to remotoring, trying to learn. Thanks!

 

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Posted by RR_Mel on Saturday, June 26, 2021 6:51 AM

I’ve been using them for years, they work GREAT!!!!




I buy my connector strips off eBay, they are called header strips.  There are two types of header strips, square pin and round pin.  The round pin are compatible with the standard NMRA 8 pin DCC connectors.  The square pin are compatible with Arduino connectors.

Both come in single row 40 pin and double row 80 pin male and female.  They advertise them as breakable but that normally dings a pin at the break so I use a razor saw to cut the strips.

Single Row Round 40 pin
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2334524.m570.l1313&_nkw=2.54mm+round+40+pin+header+strip&_sacat=0&LH_TitleDesc=0&_odkw=2.54mm+round+pin+header+strip&_osacat=0&_sop=15

Double Row Round 80 pin
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2334524.m570.l1313&_nkw=2x40+2.54mm+round+80+pin+header+strip&_sacat=0&LH_TitleDesc=0&_odkw=2.54mm+round+2x40+pin+header+strip&_osacat=0&_sop=15
 

I also make some of my connectors polarized to prevent plugging them on backwards.

I push out a pin and reverse it.








Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951



My Model Railroad    
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Aging is not for wimps.

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Posted by ChrisVA on Saturday, June 26, 2021 7:44 AM

Hi Mel,

How do you cut them from the strip and attach wires to them?
Thanks!

 

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Posted by tstage on Saturday, June 26, 2021 9:01 AM

Chris,

The connectors normally have a bevel ("V") between each contact so you can use a single-edge razor blade or an X-acto blade (e.g. #17) to score the "V" on both sides and snap them apart.  For a double-row connector I score all 4 sides.

I find a single-edge razor blade easier to control and rock it back 'n forth as I slow-ly cut into the bevel.  And, after scoring the sides, I cut all the way through with the last cut using a razor blade (rather than snap it) because it gives me a better yield.  I then finish up the cut ends with a small flat file to neaten them up. 

Whatever length or matrix of contacts you use, make a matching pair.  You will solder the wires to the pins of one connector and the wires to the sockets of the other connector.  Then you slide the separate connectors together to make the connection.

IMPORTANT: Make sure you check your wiring ahead of time to assure that the correct wired sockets align with the correct wired pins. Yes

For connecting the wires to the socket end, I pre-tin/prefill the sockets with solder and pre-tin each wire.  (With the pre-tinned socket I like the solder to be level with the socket.)  With a small amount of solder at the end of the soldering iron tip, I re-melt the solder in each socket then quickly slide its matching tinned wire into it; holding it still until the solder has cooled.

The key here is to be quick with the soldering iron; otherwise, you'll melt the plastic connector.  I use a beveled tip in my soldering iron and set the tip temperature to 700oF.

Soldering to the pins is much easier.  I pre-tin the pins like I do the wires.  Once the wires are soldered I use 1/32 or 3/64" OD heatshrink to slide over the pins to insulate them from inadvertantly touching anything metal in either the tender or the locomotive.

HTH,

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

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Posted by RR_Mel on Saturday, June 26, 2021 9:04 AM

I have a cutting mat on my workbench about 1/16” thick and put the header strip against the edge to sorta hold it then use my Atlas Snap Saw to cut the connector.

The single row connectors can be held with two pair of long nose pliers and bent to break them, if you hold the pliers very close together it won’t waist a pin.  Bend to break them, if you hold the pliers very close together it won’t waist a pin.  You have to use a razor saw to cut the double row strips.

As for wiring them I have a Panavise Jr to hold them for soldering the wires.




EDIT:

Tom, I now buy the male strips because the pin is slightly larger in diameter than the socket pin and they fit tighter into the socket.  Probably the gold plating.

 

Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951


My Model Railroad    
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Aging is not for wimps.

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Posted by tstage on Saturday, June 26, 2021 11:02 AM

RR_Mel
EDIT: Tom, I now buy the male strips because the pin is slightly larger in diameter than the socket pin and they fit tighter into the socket. Probably the gold plating.

Thanks, Mel. Yes  I'll look into that.

The one advantage that I can think of using both socket headers (vs a socket & a pin header) is the shorter profile, which can be important with decoder installations.  And, while not as tight-fitting, there is enough friction-fit to the socket end and pin ends of a socket header to hold them together fairly well.  This makes them easier to slide apart if I need a connnection to be more "disconnect-able" for dismantling purposes.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

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Posted by RR_Mel on Saturday, June 26, 2021 11:27 AM

tstage

 

 
RR_Mel
EDIT: Tom, I now buy the male strips because the pin is slightly larger in diameter than the socket pin and they fit tighter into the socket. Probably the gold plating.

 

Thanks, Mel. Yes  I'll look into that.

The one advantage that I can think of using both socket headers (vs a socket & a pin header) is the shorter profile, which can be important with decoder installations.  And, while not as tight-fitting, there is enough friction-fit to the socket end and pin ends of a socket header to hold them together fairly well.  This makes them easier to slide apart if I need a connnection to be more "disconnect-able" for dismantling purposes.

Tom

 

I agree with that, I’ve cut the lengthy pins off the male connector several times and soldered the wires to the nub.



Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951



My Model Railroad    
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Aging is not for wim

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Posted by speedybee on Saturday, June 26, 2021 2:57 PM

I got a bunch of those round machine pin headers a while ago with the intention of making plugs, but I found that after several times of plugging+unplugging, the connections become loose and unreliable. Do you guys have the same experience or did I get a bad batch of pin headers?

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Posted by ChrisVA on Saturday, June 26, 2021 3:51 PM

As a followup, what do you think is a good stratey to attach/expose the pins from the tender? Would you drill a hole or holes somewhere? Assume I have either 2 or 4 wires that need to get to the boiler. This is a small tender for a Mantua  "big 6" shifter, but would probably apply for brass too. I don't want to wreck the model with a a bad strategy. 

https://i.imgur.com/sFjA5TT.jpg

tender2

 

 

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Posted by tstage on Saturday, June 26, 2021 5:25 PM

Chris,

I like installing my decoders in the boiler (either on top of the motor or underside roof of the boiler) to minimize the number of wires between the locomotive and the tender.  The one exception to that is when there is a backup headlamp on the rear of the tender.

The photo that I posted earlier shows that connection.  Here's additonal photos showing it in more detail:

As pictured, I notched the front apron of the tender to accommodate each female socket.  To minimize the notch I epoxied styrene to the brass underside then used a miniature flat file to cut the notch; testing the width frequently with the socket to ensure that it just fit into the notch.  I then used Loctite Plastics Bonder (LPB) to adhere the socket to the styrene.

The LPB is a 2-part adhesive with a glue and an activator.  You apply the activator first with the built-in pen applicator to each bonding surface and let dry.  You then apply the glue to one of the surfaces.  The LPB will give you a few seconds working time before it starts to grab hold.  I always test fit everything first before applying the LPB.  That way there are no surprises.

If you plan to install your decoder into the tender then you'll probably need a minimum of a 2 x 3 or 6 x 1 connector to accommodate the + & - motor wires, + & - front headlamp wires, and the right rail wire.  (I'm assuming the left rail wire can just pick-up from the tender wheels.)  You could also have two 1 x 3s.  Or, you could purchase a 6-pin mini-connector that dangles between the back of the locomotive and the front of the tender.  Whatever you end up using - just make sure that your wire harness(es) don't interfere with the movement of the metal drawbar in relation to the pin on the underside of your tender.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

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Posted by RR_Mel on Saturday, June 26, 2021 7:41 PM

speedybee

I got a bunch of those round machine pin headers a while ago with the intention of making plugs, but I found that after several times of plugging+unplugging, the connections become loose and unreliable. Do you guys have the same experience or did I get a bad batch of pin headers?

 

Yes I’ve had some problems using the female sockets for male connectors coming apart after a lot of disconnecting.  That is why I went with the male header strips, the male to female stay together much better.



Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951


My Model Railroad    
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Aging is not for wimps

 

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Posted by RR_Mel on Saturday, June 26, 2021 7:56 PM

I mount my decoders in the tenders and mount the 8 pin female socket in locomotive.  I use an 8 pin male on a short pig tale from the tenders to the locomotive.





Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951



My Model Railroad    
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Aging is not for wimps.

  • Member since
    January 2014
  • 197 posts
Posted by ChrisVA on Sunday, June 27, 2021 6:58 AM

Thanks for the helpful tips everyone. I'm trying to remotor and add DCC to an old Mantua "big-six?" to learn some skills. I don't quite know what I'm doing yet, and I'm learning as I go, so advise from this group is very much appreciated! Lots of newbie and rookie mistakes at this point. 

I replaced the open frame motor with an SE15 can motor. I want to try to put a decoder in the boiler and a speaker in the tender.

Question 1: How can I get the current from the motor frame to the right contact on the motor? It looks like solder is not going to stick to the motor frame or even the original brass motor frame that I repurposed to give me the angle for the worm. Do I I drill a hole in the frame, drive a screw in, apply solder that that screw, and run a wire from it to the motor lead?

motoframe

Question 2:

This looks to be a 2-56 screw that holds the drawbar on. If I wanted to get more of these, I don't know what name it goes by, with respect to the "washer" type head? What are these types of screws called?

drawbar

 

Question 3:
I don't have a picture handy, but I'm trying to find replacement "lug" connectors that Mantua used that was attached to the end of the tender wire to get current from the tender to the motor? It looks like a small piece of brass or steel that clamps to the wire and has a hole in it that you put a screw though, which screwed into the front truck hole in the tender? Where could I get replacements for those - I dont know what name they go by to search for them.

Edit: What is this called and where could I get replacements?
lug

 

Question 4:

If I wanted to put a sound decoder in the boiler, what is a good one that is small enough to fit in there?  I looking at using a Tsunami2 TSU-1100 but is there another sound decoder that would be better suited for this situation?

 

Thanks for the help, really appreciate it!

 

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Posted by RR_Mel on Sunday, June 27, 2021 8:22 AM

1) I drill a #52 (1/16") hole in the frame and use a 2mm tap.  You could use a 2-56 tap, since almost all model railroad stuff is manufactured in either China or Japan I use metric screws.

3) I use 2.2m solder lugs for chassis connections.  All the electronic parts stores here in Bakersfield have closed so eBay is my goto.


 https://www.ebay.com/itm/224451365091?chn=ps&var=523235490827&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=523235490827_224451365091&targetid=1262779892609&device=c&mktype=pla&googleloc=9060464&poi=&campaignid=10459841973&mkgroupid=123050527180&rlsatarget=pla-1262779892609&abcId=2146002&merchantid=426106294&gclid=CjwKCAjww-CGBhALEiwAQzWxOjJvRCReoJJyObLUHOOr_uadMihzwQ6_4LlfsdRjbheagJel5Hvh1xoCQHAQAvD_BwE


Looking Good!

Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951



My Model Railroad    
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Aging is not for wimps.

  • Member since
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Posted by ChrisVA on Sunday, June 27, 2021 12:06 PM

Any recommendations on a good brand of #50 drill bit to drill into a Mantua frame? I tried this one but it doesnt do so well. Assuming slower RPM for drilling in this situation?

https://www.ebay.com/itm/391917558653

 

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Posted by tstage on Sunday, June 27, 2021 12:18 PM

ChrisVA
Question 4: If I wanted to put a sound decoder in the boiler, what is a good one that is small enough to fit in there? I looking at using a Tsunami2 TSU-1100 but is there another sound decoder that would be better suited for this situation?

Chris,

ESU makes a micro version of the Loksound 5 decoders and has a sound file for a Baldwin 0-6-0.  Here's the webpage link where you can find that.  The TCS WOW101-Steam decoder is also very good - especially motor-control - but it doesn't come in a small size and may be a bit long (1.35") to fit in the boiler.

The Tsunami2 is slightly over 1" in length so it might fit.  The Loksound5 micro is only 0.82"L (x 0.39"W) and might make a better choice.  Measuring your "free" space above the motor will dictate that.  And the Loksound 5 have excellent motor control, too.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

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Posted by RR_Mel on Sunday, June 27, 2021 12:18 PM

I just buy the cheapos from Harbor Freight or off eBay.  When they break or go dull I’m not out much.  Cutting oil helps.


Mel

 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

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Posted by speedybee on Sunday, June 27, 2021 7:49 PM

RR_Mel

Yes I’ve had some problems using the female sockets for male connectors coming apart after a lot of disconnecting.  That is why I went with the male header strips, the male to female stay together much better.

 

Thanks! I've ordered some males

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Posted by hon30critter on Monday, June 28, 2021 3:58 AM

ChrisVA
Question 1: How can I get the current from the motor frame to the right contact on the motor?

Hi ChrisVA,

If you are going to install a decoder, you do NOT want to connect the power from the frame directly to the motor. Likewise, you do not want to connect power directly from the wheels to the motor. The power goes to the decoder red and black wires. Then the decoder is connected to the motor using the gray and orange wires. The motor must be completely isolated from direct track power. You may have to insulate the motor from the frame.

Once you have the decoder installed, if the locomotive runs in reverse when it should be going forward, you have two options. One is to reverse the orange and gray wires on the motor (preferable), or there is a CV that can be changed to correct the problem. If you just change the CV you will have to remember to do that each time the decoder is reset.

I use the pin connectors too. Here is one of my installations. It is very similar to what previous posters have done:

Note that I have colour coded one of the sockets so I know which way the plugs go in. The next time I do something like this I will reverse one of the sockets like Mel does. Then there is no chance of getting the plugs in backwards.

I also put a small dab of epoxy on the plug wires to reduce the chance of the wires breaking due to fatigue.

By the way, congratulations on doing your first decoder install!

Cheers!!

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by woodone on Friday, July 2, 2021 12:20 PM

These work real well in HO models, but with N scale I have found that the NEM 651 works well and it is much smaller. There are DCC supply stores that stock these in bulk 40 pin strips. You can cut to the length you need. These will also work in your HO models.

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Posted by hon30critter on Saturday, July 3, 2021 9:48 PM

woodone
These work real well in HO models, but with N scale I have found that the NEM 651 works well and it is much smaller.

Hi woodone,

Thank you for reminding me of the part # for the NEM 651 connectors. I bought some a while ago and threw out the paperwork by mistake. Now I can number the bin for future reference.Thumbs UpBow

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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