Narrow Gauge Diesel conversion from HO.


7

747flier

Well-Known Member
OK, not totally original and maybe a slow adventure, but a while back I bought a KATO switcher on Evil Bay for cheap. These are lovely locomotives, smooth and strong pullers. I had seen part of an article about someone who had done this while back. However not seeing the whole article, I really had no idea how to re gauge this critter. Some prying fiddling and I got the trucks apart. The central spur gear has each wheel has a half shaft pressed in so one pulls the wheels off, trims the spur gear shafts and the wheel shafts and puts them back together at the appropriate gauge. So I have one truck sort of back together, the outside frames and wipers need to be moved inward, a little plastic surgery! So once I have both trucks re gauged I can adjust the electrical contacts and see if it runs OK! Then it remains to construct an appropriate WP&YR top using mostly 3D printing. Be interesting to see what sort of minimum radius this will traverse.

Photos on a round-tuit basis. For those not knowing of maritime terminology , the "Round Tuit" is a small circular railed structure in the superstructure of a ship which the Mail Buoy Watch Officer or designee stands his lookout for the essential mail buoy.
 
Under the aegis of the old Bill Clinton homily: "Even a blind hog can find a chestnut now and then". I re assembled the locomotive with the narrowguaged trucks. This required some adjustment and re engineering of the pickup system. I fully expected no action or a failure of the smoke testing (smoke leaks out).

However the loco smoothly and silently ran in both directions! With all the weight will be a good puller! . So now I have to design an appropriate shell to more or less White Pass specs. The GE 90 "Shovel Nose" would be a good candidate, though the Montreal Loco Works that now grace the D&S still in their mostly original WP paint, would be fun as well.
 
So far having issues finding good scaled drawings of the GE shovel nose Diesel locomotives. Strange as I thought I had some somewhere. The large fly wheels carry the loco a long way after running at medium/slow speed through a turnout onto an unpowered track, maybe 18 inches!

The weight is 12 1/2 oz which is pretty good for a narrow gauge loco without a shell. If I go with the GE type loco there will be room to add a DCC etc if desired. The KATO locos had an unusual snap on coupler holder, which help hold the two shell halves together, one was missing and they were setup for standard gauge couplers anyway, with a too high coupler height. So printing a couple of modified ones to hold the HON3 Kadee ones.
 
These are the GEX 3341 Locos used from the early 50's
GEX loco.png
 
I installed my version of the KATO coupler adapter (Printed) and having just a short span of track wired, could only run a train back and forth through a switch, but she pulled a nine car train like it wasn't even there. At 12 1/2 oz she has a lot of weight. Enough drawbar pull to pull a glued on draft box on a flatcar. Hard to screw in a draft box on an NG flatcar! I may print a beefier adapter though with the short train it worked well.

When I get some more track laid will be interesting to see how she pulls a grade. The prototype had some 4% plus slopes!
Bare engine.JPG
 
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I'm a crappy track layer, my soldering skills are good but I hate the rail joiners, hard to slip on! But getting enough track to run the loco and a number of cars back and forth. As everything is scratch built some cars have operational issues so some tuneup in progress. The engine is a sweet runner and able to handle tight radius. Master of White Pass, Rob Bell is sending me some ancient drawings of the GE shovel nose engines, so I should be able to proceed on the shell soon.
 
Awaiting the scanned drawings of the GE loco, then I can proceed with the shell design. So far I have roughed it out , mostly to figure out some of the kinks to be overcome in the design. I did beef up the coupler adapters. I did add some switches and have been pulling the trains through them, though some electric feeds necessary to be able to run the loco through those. Learning a few things about my cars etc and what is needed to make them good runners. The trucks are going through a mod to keep the axels from popping out, which in this case is a sleeve around the shaft, which requires a little more oomph to insert the wheels.

Cheers: Tom
 
A new in box HO KATO switcher came up on Evil Bay and I got it for $52. I received the GE Loco drawings from some ancient 1960's MRR Magazine, but they look very clear, especially the dimensions. The major effort here is figuring out how to do the first one, a second should be quite easy.

The well known White Pass modeler and real Silverton Train hand, Mike May published an article on the 211 car for WP with excellent drawings. I'll try my hand at this with 3D.

Cheers: Tom
 
Slowly getting better at track laying. As to the diesels, the GE and other White Pass Locos had six wheel tucks and my KATO's four, a major difference, but the short frame locos for conversion are such. What I wonder is if the KATO six wheel trucks are identical in their power train and could be incorporated in the shorter frame by doing surgery on the fuel tank area. Anybody out there have a KATO six wheel truck loco?
 
Going through what you have done, and doing, - I would say that the best plan would be to stick with the four wheel trucks. If they work good, then dont screw with it?
 
As I mentioned, I found a second KATO switcher, NIB for $52. So for now I'll be happy doing shells for these locos, under the KISS principal. However also keeping the eyes and ears open for possible six wheel projects. All the WP road diesels were six wheel units. Interesting to see the Durango-Silverton obtained WP's DL535E engine/s still in WP colors. If it turns out that a six wheel conversion is possible, then I will explore that possibility. Rob Bell and Mike May converted an Australian engine (six wheel) to the experimental USA engine WP had as a switcher.

Rob kindly sent me drawings of the GE shovel nose engines which will help a lot. Being away from the hobby for many decades, the old MRC power pack have is a pulse power type, which is apparently dangerous to the electronic health of many new engines. The idea is to eventually go DCC and I have a NEC unit for that, but currently DC. Anybody have thoughts on power packs and if this is a serious issue (pulse power).

Tom
 
Some track laying ensued, I now have a loop, a key ingredient of any under the Christmas Tree train set. However loco and car wise I can run the thing and check for any track or switch issues She's a good puller which means I need to get back to designing the GE shell.
 
Now I have two running chassis, new in box KATO NW2 arrived today at the PO, fast delivery. Seems a little sacrilegious to take the dermal tool to a never run loco! She seems a little stiff, being brand new. Maybe just a small amount of tuneup on the pickup setup. Have to install couplers which take an accessory holder, which I printed for the first one. I'd need to make a much larger layout to require a double header! I did find an article on how to DCC these.

Tom
 
This is HON3, it would not be possible to re gauge the KATO loco's further than HON3 because of the width of the gearbox. I had need for some smaller radius locos as my inner loop is a bit tight for the two Blackstone K27's I have.
 
747flier said:
This is HON3, it would not be possible to re gauge the KATO loco's further than HON3 because of the width of the gearbox. I had need for some smaller radius locos as my inner loop is a bit tight for the two Blackstone K27's I have.
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ok im going to build a Hon30 industry switcher and some car for my layout.
I also scored some On30 engine the other day so im looking at building a micro layout for them.
 
Murphy is quite the lawyer, perhaps he should be appointed to the Supreme Court? I accordance with his general law, if something can go wrong... Now that I have two converted loco chassis, I decided to see how they ran as a double header. It turned into a tractor pull competition with the older broken in loco having slight advantage. In the KATO case it is possible to re insert the motor/flywheel assembly backwards and get a loco that runs the other way. Just took about 10 minutes to take it apart and reverse the motor drive train assembly. So yet indeed they can run as a double header, now...

Good luck with your new project! Tom
 
Both conversions run well and are very quiet, even without shells. Currently I am working on shells for this pair. I successfully printed a test shell which gives me guidance as how to mate this to the chassis, minor modification seems to be in order but it's an overall good fit. Plenty of room in the cab area for DCC controllers and sound if desired.

The loco's have a number of grills along the side, often these would be of brass etch. In this case I was able to make very convincing and useful grills by designing these with 0.25 mm openings on a 0.4mm spacing. I think I will make the shell walls somewhat thicker to increase rigidity.

Tom
 
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A decision to thicken the shell was a mistake, sometime less is more with resins. However making progress on how tp position and support this shell. The rear coupler module needs to be extended a little, quite a bit of overhang at the aft end beyond the truck.

It does look cute running around the X has tree loop, quite a small engine as these things go!
 
zzr1200guy said:
ok im going to build a Hon30 industry switcher and some car for my layout.
I also scored some On30 engine the other day so im looking at building a micro layout for them.
Click to expand...
Not trying to hijack this thread, but I went down the HOn30 rabbit hole (again). I'm back to HO standard gauge. It was too small for my mid 60's eyes and DC wiring was a PITA. I'm spoiled by the simplicity of DCC.;)

Here's the thread with my engine and rolling stock conversions. https://modelrailroadforums.com/for...w-gauge-of-my-youth-2-7-layout-started.34935/
 
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