My Last Locomotive Project

[jonathan]

Doneldon,

Thanks for the compliment.  I enjoy looking at other's work as well...

How small do LED's get?  The smallest regular bulb I've found is a 1.5 volt.  It's tiny--half the volume of a GOR bulb.  Even that wasn't going to fit.  Probably this is beyond my skill level.  I love to tinker, but I also have limitations.

This is almost a job for fiber optics.  I doubt if I will go that extreme.  For now, I've glued a lens on and can always pull it off and start over... from bare metal if I have to.  I bought extra lenses and plenty of paint:






Speaking of 1.5 volt bulbs, that's what I'm using in the headlight.  I've tested, completed, and retested my smokebox project and it's ready for installation:



I may have used too much resistor, but better for the light to be a little dim than have to replace bulbs and start over.  In order to feed the wiring through the boiler, I had to cut the top off the boiler weight:



I believe I can put most of the weight back after I've completed the shell (I saved the pieces).

Thanks for the longer drawbar idea.  That sounds like the answer.  Of course, there may be no problem.  I didn't run the loco on my layout before I took it apart.  Doh!...

Waiting on the motor...

Regards,

Jonathan

[Doneldon]

jonathan-

LEDs get very small. The so-called surface
mount LEDs are almost too small to measure.
They are maybe 1.5 x 2.0 mm, ideal for
placement in a light housing.

                                                  -- D

[BestSnowman]

Fiber optics may not be that extreme of a solution. The other day I was looking for some lighting options for an idea I had and found some ready to go fiber optic solutions. I don't recall them being expensive, when I get home I'll try to find more information for you.

[J3a-614]

Re: Potential short circuits between engine and tender

Taking care to avoid such short circuits should not be too much of a problem, and you shouldn't have to lengthen the drawbar, either.  The paint on the handrails of both locomotive and tender will help prevent shorts by insulating each from the other, but this will not likely last very long.

The first thing to consider is somehow to insulate the tender body from the frame, and hence from the locomotive, which is of opposite polarity.  Beyond the paint on the handrails, mentioned above, the next thing to consider would be how to make the tender body electrically "dead."  This could be by insulating the tender body from its frame with thin layers of paper, possibly a coat of insulating paint or nail polish also being insulating combined with plastic screws substituting for metal ones.  The late John Allen supposedly cobbled up a whole new tank frame and bottom out of wood for his tenders (and he had to wire truck posts together to get current flow).  He took advantage of this work to improve both enngine and tender with a weathered paint job, etc., and a standard drawbar that gave consistent locomotive and tender coupling distances, allowing him to use any engine with any tender.

In any event, I would not alter the drawbar unless there was no alternative.  Many older models had their appearance degraded by a too-long drawbar.  This engine is not really huge, and your curve radius doesn't sound too extreme for it.

Have fun!

[jonathan]

Interesting... As I painted the shell and the frame seperately, there is the possibility I've unwittingly insulated the shell already.  Each piece has a coat of primer, gloss paint, and two coats of dullcote.  I like the insulating paper or fingernail polish idea.  I would have to tap the tender holes, but I have seen plastic 2-56 screws that my LHS. These seem like simple fixes that will be relatively invisible when done.  

Thanks, again!

Regards,

Jonathan

[ebtnut]

I note that the drawbar already has two holes in it for close coupling and wider space coupling for sharper curves.  My guess, based on old experience with PFM's, is that if you use the wider spacing, the loco should be OK on 18" curves. 

[hotrainlover]

Jonathan,
I drilled a hole up through the tender into the brass light housing.  Then I used a clear sproon, (from a Athearn window kit) to transfer the light from inside the tender to the lens area.  I used heat sink tubing to attach a 3mm LED bulb to the bottom, added a resistor, and it worked well.  I have noticed that my Bachmann 0-6-0-t Saddle tank has this arrangement for the tender light.
(P.S.  That is where I  got the idea!)

hotrainlover

[jonathan]

Happy New Year to one and all!

You have given me some great ideas for the tender light.  I like the 'transfer the light' idea from hotrainlover.  That might just work, in other words, something I might be able to handle, without doing any real damage.

Anyway, I will continue on with other parts of the project for now.  I've begun tinkering with the motor.  Here are a few shots of my efforts so far.  Note that the motor is just laying in position and not glued in, yet.



I'm afraid I won't have room for a backhead.  In fact, with the flywheel and large size of the motor, I can just barely get the shell down into position.  The flywheel sits in the top of the cab.  I suppose with the flywheel painted black, and a crew in the windows, it might not be too noticable. I really wanted the flywheel in front of the motor, but couldn't get the arrangement to fit.  I couldn't get the shell down over the motor that way.



I'm using a kind of ball and socket arrangement to connect the motor and gearbox:



I'm using some old, open frame motor pieces to construct a mounting bracket.  There is lots of epoxy smeared around these pieces, in an effort to isolate the motor.  When I decide the angles are just right, I will use silicon to attach the motor to the bracket.  The bracket screws to the original mounting plate, which is adjustable as well.  With this arrangement, I can still remove the motor if needed, for servicing.





Notice there is a strip of electrical tape, as a precaution, to prevent the left side wire from touching the frame.

The motor wiring is fairly well hidden under the frame pieces:



I will be doing a lot of testing before I add the silicon.  However, at this point everything seems to line up well.  Most importantly,  I made sure the wires were arranged so this loco would travel the same direction as all my other locos.  Polarity seemed like priority "1" when I started tinkering with this part.



Regards,

Jonathan

[Doneldon]

jonathan-

I must admit, I laugh a little every time I see the name you've given this thread. Not at you, mind you, but just at how far from reality it really is. I predict you'll finish your "last locomotive project" and start another before summer even gets here.

You're not only making good progress, by the way; what you have looks very good. I don't think you need to worry about isolating the motor from the frame as can motors take care of that for you. And you don't have to worry about gluing things down prematurely, either. While silicon sealer sticks like mad, it's also very easy to remove should you need/want to do so. I'm sure you know that.
                                                                                                          -- D

[jonathan]

Thanks, Doneldon. 

I really hope this is the last project.  There's really a lot of time and money that goes into one of these things.  I can't go on forever.

The motor does look good... before the shell gets put on:





It really takes some effort to get the shell on.  I have hand-turned the fllywheel, and nothings seems to be rubbing so far.  This will take some tinkerin'

Regards,

Jonathan

[Doneldon]

Jonathan-

Speaking of hand turning the flywheel, you could take it to a machine shop and get it turned down a couple of hundredths to get a wee bit more clearance without materially affecting the motor's performance. (I'm assuming you do not have tooling which would let you do this yourself.) You could try spinning the flywheel with an electric drill while holding a file against it. I think that would take the size down some but it may not result in a completely balanced flywheel which could lead to potentially destructive vibration and wear. Either way (or neither way), good luck.

                                                                                                                 -- D

[jonathan]

Doneldon,

You're right, I don't have those kinds of tools.   And thank you; a little luck always helps.

Did some more tinkering this morning.  Turns out, I can lay the motor sideways and still get the shell on.  It's a little tough, and I may end up filing a little on the inside of the shell.  However, it does help with the fit a great deal.

I can turn the motor back around and have the flywheel on the inside where I wanted.





I also made a bronze clip that stabilizes the gearbox:



It's lined with electrical tape on the inside, and a small metal bar (wire) prevents it from springing loose.

The motor is still adjustable, so I can flatten it out some more.  However, it completelly fills the cab of the shell.  I'll be lucky to get a crew in the windows.  Oh well, I knew that might happen.

Regards,

Jonathan

[jonathan]

OK,

If you're interested, here's a minute-long video of the initial motor/mechanism test.  Be sure to crank up the volume so you can hear the whir of the horned connecting rod.  Cuidado!  The sound of me changing polarity on the throttle could hurt your ears.   Power is turned to 50% in both forward and reverse:  



Next, a few shots of the shell placed on the frame.  I need a friend with a dremel and cut off wheel so I can remove the end of the motor axle.  Well, at least it all fits in the cab.  Perhaps a little trickery with paint and mirrors will hide the oversized motor:





My next update might not be for a while.  I have to do some boring stuff.  Like, I may need to reverse the motor wiring since I turned the motor around   ;  lots of touch up work to do on the frame; a test run with the tender to check for shorts... and oh, yes... fun with chemicals:



Regards,

Jonathan

[ebtnut]

Jonathon:  Just a caution re:  the Tarn-X in the pic.  Many of those old PFM's were sprayed with a clear lacquer coating over the brass at the factory.  You may need to strip it off first if your intent is bring up the bright brass.  If you are just cleaning it up for painting, then a good detergent and water wash will suffice.

[jonathan]

ebtnut,

Thanks for the heads up! 

I didn't use tarn-x on the tender, steam chest or pilot.  I considered it for the boiler because of the stains and overall dark condition of the brass (handled allot).

I will test a hidden area with some thinner and see if anything comes off.

My concern is getting the paint to stick.  A lengthy vinegar bath seems to have worked with the other parts.  Can save the strong stuff for my wife's baubles, if not needed for the loco. 

Thankfully,

Jonathan