Best Of New Brass EP-2 assembly & Mod clinic

[u18b]

well, with the issues with the mechanism and wiring worked out....

I'm ready to turn to detailing.
There are a few very important details to add.  Some in brass, some in plastic- as needed.
The most important is the steps.  The etched steps are a great addition (since the 1983 NJ model had no steps) but they just don't do justice to the real thing.

There are handrails that go up the side of the steps.

Now, if I'm going to be soldering on a rare and expensive brass model....

I figured it was time to move to Resistance soldering.

A basic set-up from Micro-Mark is about $200.  But the better set runs for about $445.  Yikes! 

I've been reading on the net about people who made their own set-ups.
I was almost ready to pop for the $200 set, when I decided to go for the home-made set up.

While there are several tutorials on various websites I came across, the truth is- some people are great hobbyists and come up with very creative ideas..... but they are just not very good at technical descriptions.  I hate reading someone's step-by-step tutorial.... and STILL feeling like I'm not sure what they did or how to proceed.

So I have decided to write my own tutorial.

It is not N scale specific, so I will probably publish it as a PDF on my website:  u18b.com

Should have it finished before the weekend.

Then I should be able to get back to detailing.

Ohhhh. and the Resistance Soldering Station that I built cost me somewhere around $35 and is comparable to the $445 version.

[skytop35]

Ohhhh. and the Resistance Soldering Station that I built cost me somewhere around $35 and is comparable to the $445 version.

+1

[u18b]

Thanks to all who have been following this thread.

Having just a little delay.

I took a side excursion to build a resistance soldering outfit.

I had success.






The hold up is that I wanted to make a PDF article on how I did it.
So I'm building a second to show the steps.

But there is one part that I had on hand for the first- but not any more.
And I could not find it locally.
So I special ordered it.

When that part comes in next week, I'll be able to finish this little side excursion and get back to work.

Stay tuned.

[u18b]

I finished building a Resistance Soldering Station.



It was much more involved a project than I thought.  Not the device, but all the photography, and thinking, and writing.  It is 31 pages- which sounds like a lot, but my hope is that it is VERY clear.  Magazines just can't do something like this.

So download away.  And enjoy.  I'd love to know if you build one and it works.  I can already see that this will be a very valuable tool in the future.  I've already used it to repair one of my damaged brass locomotives.

http://u18b.com/wp-content/uploads/2013/03/ResisSolder1403.pdf

I tried VERY hard to keep the size under 1 meg so as to reduce my bandwidth hit from my website.

[mmagliaro]

Downloaded it.
Read it.

FABULOUS!

Ron, the things I always wondered about with home-building one of these were:
1. Where to get carbon electrodes?   People get them out of the inside of carbon batteries and such, but
that always seemed like a royal pain, and they are so thick.  I'm surprised that the mechanical pencil
leads work.  I didn't think they really had that much carbon in them.  But that's great!

2. What to use for a power supply?  I mean, I'm not afraid to build one.  But I had no idea what voltage and current
I really wanted to shoot for.  A PC switching supply.   Ha!  You can get those anywhere and CHEAP, as you point out.

QUESTION:
Do you have any idea how many amps your probe is really drawing?  Did you by any chance stick an ammeter in
there and see if it's drawing 5 amps, 12 amps, whatever?   Your supply is rated for 22A at 5V, so you're not drawing
more than that.  But I've always been curious about how much power really you really need to make one of these work.

And one more question... how finicky are those pencil leads when you make a joint?  I would have thought they would
break off very easily and be a nuisance.

Loved your paper. 

[Sokramiketes]

Nice Ron.  My only comment would be that the American Beauty Ni-Chrome electrodes are extremely cheap.  With a much longer life and strength than the pencil lead, I think they would still qualify for your budget build at just over $10:

https://www.americanbeautytools.com/site/Resistance-Soldering/152

[u18b]

Thanks Max,

I'm with you.  I see that many people consider AA or AAA batteries as a source for carbon electrodes.
Who knows, maybe there's nothing to it... but I just don't want to deal with acid or a mess.

As for mechanical pencils, I'm sure there are differences as to carbon content.  My paper shows differences between two brands.  I might have just had dumb luck that one of the brands was high quality in the carbon department.

As to workability of the micro-electrodes I'm using.  Yes, they are a bit delicate.  But they are also cheap cheap cheap.

You have to remember, this is a different kind of soldering.  In regular soldering, the heat is transferred by touch.  The more surface area of the tip that touches, the more heat is transferred.  I know that when I'm trying to UN-solder something from a PC-board, I often press down pretty hard-- trying to transfer as much heat as possible to get that part loose.

This system works in an entirely different way.  Pressure has zero effect on heat.  Heat is only created by one thing-- electricity flow.  So you have to train your brain to be very delicate with these electrodes.  Let the electricity do the work.  So in answer to your question, once your brain is trained to touch and not press, I found I broke very few electrode-- until they get very thin that is.

I have never hand laid track, so I am wondering if this setup would be ideal for that application.

As to actual amperage, no it did not occur to me.  When I get a chance, I will see what I can find out.

[u18b]

Nice Ron.  My only comment would be that the American Beauty Ni-Chrome electrodes are extremely cheap.  With a much longer life and strength than the pencil lead, I think they would still qualify for your budget build at just over $10:

https://www.americanbeautytools.com/site/Resistance-Soldering/152

Mike, thanks for the suggestion.

I'm wondering if the product by MicroMark is similar.
http://www.micromark.com/extra-tips-for-needlepoint-electrodes-set-of-2,8240.html

They are a fraction cheaper.

[u18b]

Let's move the resistance soldering topic to another thread.

I started this......

https://www.therailwire.net/forum/index.php?topic=32362.0

Thanks.

Looking forward to doing more on the EP-2 soon.

[nkalanaga]

"As I say in the book, it did not work (first try) with 12 volts.  If the resistance is the same, then V= IR...... V/I = R.  So if the voltage goes up by almost a factor of 3, then the amperage should go down by about 1/3 (if I understand the math).  So I'm not sure why it didn't work."

No, if the voltage goes up, and the resistance remains the same, the current will INCREASE by the same factor.

Example:  1 volt through 1 ohm = 1 amp:   1V/1I = 1R
3 volts gives 3V/?I = 1R, where you need 3I to balance the equation.

[u18b]

Here is a quick update.
Got a little side tracked with the resistance soldering issue. 

Springs have been ordered.


Overall loco is built.
About to make some changes in detailing.

Forming a plan.  Been spending a good amount of times researching, studying photos, and thinking.

Here is a hi-rez shot of the as-delivered look.
http://upload.wikimedia.org/wikipedia/commons/0/09/MILW_Bi-Polar.jpg

Now, while my model has some major differences, this photo is adequate to show some details that I have been investigating if I could add.

Here is the same photo, cropped and sized for our purposes.



1.  Green.  The most important must-add detail is the railing for the ladders.  These are VERY distinctive and they will add significant support to those frustratingly delicate step ladders.  Since this ladder is HIGHLY susceptible to eventually getting broken off from so much bending, then these rails will help.

Notice the left rail comes through the floor and up to the cab wall.  This is missing on the model.  There is another little tiny rail right where the step meets the walkway.  That would be pretty small in N scale, so I will leave it off.

2.  Red.  While Kumata did a WONDERFUL detailing job on these models, I'm really sorry they left off the jacking pads.  They are pretty distinctive.  But they are also pretty small.

I have been pondering how I might add these, but I see only two solutions.

a.  Make some out of styrene.  They would be pretty small and delicate.  But more important- they would have to be glued on.  More than likely, they would just fall off one day.

b.  The part really needs to be etched.  That way it could be carefully soldered onto the walkway edge and be permanent.   But that is pretty fine etching – beyond my skills.  And the cost to get someone else to do it would be prohibitive.

So sadly, I plan to leave these off.  This might fit into the 3-foot rule, especially since they are black.

3.  Orange.  The prototype has two hoses under and around the coupler (one is the brake line).  I may trim the MicroTrains trip pin on the front, and add both of these to the front.  Even if one hose is plastic, I can drill the hole now and add it later.

4.  Purple.  The uncoupling bar is pretty distinctive.  I'd really like to add this, but I'm leaning away from it.

There is already a primitive part molded into the cast brass piece- but you can hardly see it.  To replace it, I would have to totally disassemble the truck and file it off.  Drill new holes for the pins and fashion a new wire.  The wire is not the problem, drilling into the heavy cast brass is.  I don't have any high quality #80 bits and they would probably break.

I'll have to do some thinking on this one.

5.  Yellow.  There is some kind of electrical socket up high on the face.  Missing on the model.  While it may lack some detail, I will probably drill a hole and solder a wire sub into the hole.  Will look a LOT better than nothing in that empty space.

6.  Light blue.  While the model has a lot of grabs, they missed this one.  Actually, while it appears to have one as delivered, a matching one was added later- as can be seen in this later photo.

http://upload.wikimedia.org/wikipedia/commons/7/76/Milwaukee_Road_EP-2_electric_locomotive.JPG

The challenge will be that these grab will need holes drilled where the shell meets the cast front face.

7.  Dark blue.  There is a large and significant grab iron (step) below the cab on the left side only of each cab.  Hard to see in the photo above, but captured in this highly detailed brass HO model.

[u18b]

Well, I spent probably 4 hours today.  Reading,  searching out photos.  Getting ready for the detailing.

A lot of thinking.  Instead of giving up on the distinctive jacking pads, I spent a good deal of time trying to solve the problem.

Tried some tiny square tubing.  Hmmmm.  Better than nothing, but still not right.  And too much trouble when I tried to cut off a sliver cross-section.

I then I had a brainstorm.  A lot of experimentation then followed.

And I think it will work.  I still have to actually install then, but wait till you see them. I have to admit, it is rather amazing.


I also figured out some of that piping around the coupler.

The big pipe on the left side is for water from the boiler.
You passenger guys would have known that, but I had to figure it out.

So I'm only just getting started on the extra detailing.

First step was to disassemble a cab- almost totally.  Wow depressing to see it back like this after coming so far.



Then I printed some photos on card stock to have in front of me.




More coming in the next day or so.

[u18b]

Finally time to do some detailing.

In my research, I discovered this cover photo on a book had almost all the details I will be adding referenced above.



When drilling, it is often helpful to make some kind of mark to help the drill bit stay put.  An awl is a pointed object that does just that.  This awl is made by placing a pin in a drill.



Starting with the grabs up top.  I studied photos to see where to start in relation to the etched hinges on those hatches.  It looks like the best place to drill will be at the solder seam.




Using the awl, I mark the solder for the drill spot.




I now hold my breath as I use cheap quality #80 drill bits to drill the holes.  (sorry, had to throw that in.  We had a discussion recently on how drill bit quality has gone down in recent years).
Notice how I use my fingers as braces, guides, and supports.




Now the matching hole on the other side.




Now the hard holes!  Had to clear the number boards.



I had some .008 wire in stock.



Good guestimate for size.



Test fit the wire.  It is a bit too short.



So I bent it again.  Don't forget to put a slight curve in it.



Fits better now.  Time to solder.  I want there to be some space between the shell and the rail.  So I insert a little piece of business card.




I now hold that firmly in place and turn the shell over so I can get inside.




I then bend the wire ends toward each other.  (see red).



Solder the wires to each other and to the shell.



Little minor tiny bends with a razor blade in the gap gets them into final shape.
That's the look that was missing.

[u18b]

Now the electrical connection.
I had some 1/32 brass wire.
Might be a little large, but it looks OK.




After cutting, I file the cut smooth.  I then switch to a fine file.




Hahaha.  Normally, we want to scrape off all the flash and excess around the edges.
But not here.  I WANT it to make it look like there is a little hatch.




Drill the right size hole.



And test fit.



Solder in place on the inside.
Looks better with it being present.  Glaringly absent on the original model.

[u18b]

Continuing on with the cab.
Time for the horn.

I did not have any proper brass horns.
But the horns on an Atlas FM H15-44 looked about right.



STUDY THE PHOTO!!!!!!!!!!  Don't get confused, Bearden.
OK, this is the A end.  My photos above show that the horn goes over the cab window.
(on the B end, it goes on the nose).



Drill a #72 hole, and mount horn.
Progress.



Now I can move to the walkway.

More in the next few days.