The story of a box

[nah00]

This is the story of a box. While poking around the back shelves of my local hobby shop I found this tucked away.

 

Never one to ignore a Tomix case be it labelled or unlabeled or dirty or clean, I had to know what was inside.

 

 

To my surprise it was a very muddy 381 Series. I was able to see the car number printed on the trailing KuHa so I took out the motor car on a whim to see if I could get it to turn over on the test track at the store. Once I got the chassis apart and spun the motor a few times it came to life! $5 later it went in a bag and came home with me.

 

 

This is what was left after scrubbing (most) of the mud off. I should explain what happened to the train to get it in this condition at this point. A few years back we had the remnants of a hurricane slide up along the interior of the Appalachians and pretty much stall over western Pennsylvania. The shop ended up flooding with 4 feet of water on the first floor and over $90k in stock lost. It would appear this one got lost in the mix somewhere and was set aside for some unknown reason. 

 

 

Disassembled and scrubbed, not using that toothbrush anymore.

 

 

The motor came apart pretty easily. Cleaned all the mud out and used a wire brush to get as much of the rust off of the motor as I could. Disassembled the worm gear housings and got all the gunk out of them, same with the gearing on the trucks and the chassis itself. Cleaned off the metal chassis itself with a fine cotton swab and rubbing alcohol and polished the copper strips with the same. Put it on my layout and let it run at half speed while I more thoroughly cleaned the other parts, only lubrication I did was two drops of lite oil on the worm gears and two drops on the transmission gears under the trucks. The motor still make a scratching noise from time to time and I can hear wheel slippage, I'm thinking i may have to add a SMALL amount of grease to the worm gears. 

 

 

All back together and for the most part clean. I have feeling I'll be finding mud spots on it forever. Doesn't have the front emblems or the Shinano signs on it yet in this picture. 

 

So now on to the parts I can't figure out. I don't want to do it as a JNR train so I'm not worried about those decals but where do the red ones on the right go?

 

Also haven't been able to get the lights to work yet. The one lightboard does work, came on right away when I put it in my Super Yakumo. However the printed circuit board for the other one was cracked. I tried to solder it together the best I could but it still only gives out weak intermittent light when on the clean Yakumo. I don't suppose anyone has a spare old Tomix 0707 light board they're not using? Also I can't figure out why the lights won't work on it, used a multimeter and even though they're still a bit dirty the springs on the trucks are putting out 6 volts at half throttle but I'm getting nothing through the weights in the car. There is corrosion on the plastic between them though, could that be causing a short? 

 

As you can see, this isn't the end of this story. I still have a bit of work to do but I'd like to get this train running like new, lights and all. I was thinking for the light board of just taking off the broken end (it's the side with the contacts) and just using wire to solder it right on to the weights/pickups. Good idea or bad idea?

 

 

 

[railsquid]

Nice fine! Can't really help with your questions though; soldering might be an option but hard to say what I'd do (no expert) without seeing it close up.

[kvp]

You could use a multimeter in continuity tester (beeper) mode to find shorts or broken contacts. Also imho getting new lights would be easier than soldering. Especially if you could fit modern led ones.

 

ps: that train survived the mud surprisingly well...

[Gryphr]

That's some awesome recovery! And 5$ for it is a pretty good value too :)

 

I think the red Decals on the right of the sheet would be for a longer Bonnet-Style Cab car, most of them seemed to have these red "eyebrows" over the headlights:

https://commons.wikimedia.org/wiki/File:JNR_class_485_EMU_Kuha_481-26_at_the_Railway_Museum.jpg

Edited October 15, 2017 by Gryphr

[cteno4]

Nah,

 

excellent, you da man! You have the title of dr Frankenstein now! That's the best resurrection I've ever seen. And you did not have to go up on the roof with a metal kite in a lightning storm to give it life!

 

im guessing there is another cracked trace on the board that barely touched and some corrosion or muck in the crack. I think kvp is right that it may be best in the long run to get new, modern light boards even if you need to mod them a bit to fit. Not sure of how the weights and contacts look on this model to help there.

 

do you have an ultrasonic cleaner? They are perfect for this sort of clean out as it will loosen stuff trapped under stuff and in small pockets and cracks. Especially good for motors and trucks.

 

Could there be another surface to surface contact somewhere between the trucks and the top of the weights that's hidden and corroded? Corrosion loves to happen between two dissimilar metals are present near each other with moisture between them. One metal then takes the brunt of it big time then and more than just a single metal with moisture.

 

also a tiny midge of very light weight bearing oil on the motor bearings, those can sometimes squeal when dry.

 

kudos again nah!

 

cheers

 

jeff

[mry1210]

nah00,

I've seen the before and after photos of the shop. It was amazing anything in the town survived. I drove thru there last week and now seen the trendy coffee shop across the street.

Nice to see the comeback.

Anyhow, I have an ultrasonic cleaner sitting on a shelf. If want to try cteno4's advice, it's yours for the using.

 

Brian

[Quinn]

What a superb find! Looks well worth the restoration work. 

[nah00]

Thank you for all of the compliments and encouragement. I'm happy to say that after many hours of cleaning and at least 4 complete motor tear downs it runs just as well as my Super Yakumo. Only part that had to be replaced on the whole train was the light board (even though the one worked fine I bought a pair since they were only $6 each at HS). Here you can see the two light light boards, pretty each to figure out which is the newer one, sadly it's not a LED:

 

Here was attempt at repairing the old one. The next morning when I went back to it both filaments had broken. My only guess is possibly too much heat from the soldering iron? I was trying to work quickly to just cover the gap but solder isn't terribly cooperative. I circled the bits I attempted to repair:

 

Going with new light boards was the best idea. However I have to do some work on the 'Shinano' signs on the front and back, there's quite a bit of light leakage/diffusion that could probably be solved by simply painting the light block sign black on all sides save for the sign side and where the light enters. The biggest problem with getting the lights to work did turn out to be corrosion - the copper spring sitting against the weight had created a thick enough layer I had to use a wire brush on it as well as some of the wheel backs and wipers (I can honestly say I put some blood into this project, got jabbed with a bristle more then a few times). After that the lights worked fine, had to a little more work on the last car than the first to get the tail lights working.

 

The motor took a bit more work. It was making an awful high-pitched whine/squeak indicative of lack of lubrication. Took me a while to isolate it but finally did and was able to pull back the motor housing just enough to get access to spray in some canned air as well as get a drop of oil in it. I also think it didn't hurt that I dunked the whole motor in 93% rubbing alcohol. It now runs just as good as any other train for the time period and I've noticed over the course of several sessions of running it that the motor housing in the car is feeling progressively less warm, always a good sign.

 

This was a great learning experience and not to mention felt like a pretty big accomplishment for me bringing it back from the dead. It was a very fortunate thing that I had the Super Yakumo that I could use to test bits on as I worked, I knew I bought that train for some reason other than the color scheme. Biggest takeaways from this:

 

1. Use only 93% rubbing alcohol. The 70% stuff doesn't cut it for a job like this.

2. Spend the $5 on the small tube of white lithium grease and you have enough for 3 lifetimes.

And finally:

3. Don't get discouraged when you fix one thing only to find out that it made something else not work.

 

On another note, I was also able to save the plastic case it came in and thank you Casco for re-releasing the foam inserts in a few months since the one in the case was beyond saving. 

 

And a final note, the decals were indeed for the bonnet car. Evidently buying the 2000 Tomix catalog was a good move on my part, after looking I was able to see which sets shared this set of waterslides and sure enough the bonnets did. 

Edited October 23, 2017 by nah00

[Welshbloke]

I love fixing stuff like this. Closest I've had to date was a couple of random Kato coaches (a KuHa 455 and a KiHa 65) described as being in poor condition. They looked as if they'd been involved in a paint fight, but luckily the paint turned out to be water soluable. Some sponging with warm soapy water and a bit of fingernail scraping got rid of it and left the original paint in surprisingly good condition. The KiHa 65 was joined by a cheap old KiHa 58 in need of a good service and clean, they now have interior lighting but are too old to have head or tail lights. The KuHa 455 is sitting with my ten car set of the type as a spare coach.

[cteno4]

Great work nah! 

 

Fixing traces like that is super delicate work. You have to get the area very clean as any little bit of contaminant will sour the solder blob. It can help to take a single strand of wire out of stranded wire and put it across the gap and solder that down, you will find that hit helps make a bridge and a huge blob of solder is not needed on each side to mate up. Also placing a tiny tinyndab of flux on both sides helps to get the solder bonded fast to each side. Also getting the hair thin solder like .3mm. Usual problemin fixing traces like this is what you saw, something else gets overheated like the bulbs.

 

70% does work some as the water in there can help lift some things, but then have to use 93-95% to push out all the water. With the ultrasonic cleaner I usually do a soap bath, then just water, then 70, then 95.

 

jeff

[cteno4]

Btw, these dental brushes are great for contact cleanup with your rototool. They are nylon so not as agressive on thinner strips that wire brushes can be, but clean well and are tiny so can get into the tinier spots. They work about as well as the fiberglass contact cleaner pens, but can get into tinyier spots and don't leave small bits of fiber glass behind that I hate! Also metal brushes can leave behind a lot of scratches that are places gunk starts collecting fast.

 

few shapes to choose from. Very inexpensive.

 

https://www.ebay.com/sch/i.html?_from=R40&_sacat=0&_nkw=dental+brush+10+nylon&rt=nc&LH_BIN=1

 

If you find they are too tiny for your chuck or too close to a bulky chuck then try a dental bur adapter that will hold the standard 1.6mm dental shafts in a small chuck that will get then rototool chuck out of your view and light some.

 

https://www.ebay.com/sch/i.html?_from=R40&_sacat=0&_nkw=dental+bur+adapter&_blrs=spell_check

 

btw dental burs are great as well when you need tiny grinding bits. Most that come with rorotool sets are a bit big for a lot of fine modeling work

 

https://www.ebay.com/itm/Diamond-Burs-FG-102-for-Crown-Bridge-Preparation-Dental-Molar-teeth-10-Pcs-Set/201979000188?epid=9004572882&hash=item2f06e2f57c:g:j84AAOSwHMJYJBMJ

 

gotta love dental tools, nail art tools, and acne tools for hobby stuff!

 

jeff