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Scratchbuilding a Shay (NWSL/Keystone/MDC)

From Siles Bazerman, 10-Aug-97

Part I


These are notes on scratch building a Shay, and are not intended to be step by step instructions. They presuppose that you have a background in scratch building as this in definitely not a beginners project, just as modifying the Keystone Locomotive Works Shay to take the NWSL power kit is for more advanced modelers.

The techniques mentioned here are what I used in building my 16 Ton T-boiler Shay in HOn30 and are based on over 40 years of scratch building and kitbashing locomotives. All dimensions given in feet and inches are scale, while those in decimals and fractions are actual measurements.

This project is based on the NWSL power kit for the Shay. I know that at the present time this is hard to find due to a problem with Sagami motors. However, there are many kits sitting uncompleted on workbenches, on dusty shelves in old time hobby shops and lurking in unexpected places. Also, all the mechanical parts are available from NWSL as individual items, and they might even be persuaded to sell the kits sans motors on request. I use Micro-Momotors which are expensive but give actual scale speeds. My Shay runs at 15 mph at 12 volts with a 1016 motor and a 4:1 gearhead. With the motor in the kit it ran at about 35 mph. What is worse starting speed was about 9 mph while now it is about 1.5 mph.

Start with the power trucks. This is the key to a smooth running model. The inside frame, (black plastic), is the same part for HOn30, HOn3, or HO
standard gauge. It will probably need thinning from side to side to clear the wheel sets and pickups. Be sure to take an equal amount from each side. I found the best way to do this was by using 150 grit garnet paper glued to a flat surface and alternating sides every 5 passes. You might also consider removing the black plastic insulation on the wheel sets that extend inside the wheels.
Oh yes, be sure to check the back to back spacing on the wheels as they are not always correct.

Next, check that the wheels roll free with just the bottom plate in place. You will probably have to widen the U-shaped channel a little by scraping on both sides. The axles should drop in freely but should not have excessive free play. Check the gear mesh while you are working here, the slots might have to be deepened for a proper mesh. If this is needed use a round file of the correct diameter and work very slowly.

At this point clean up the frames and the wheel sets with a little soap and water and assemble the frame, wheels, and bottom plate only. The truck should
coast down a 3% grade without any push. Now is the time to install the kingpin on the truck. I have never been able to get the supplied kingpin to hold
securely in the frame, so I used a nylon 0/80 fillister head screw with the head turned to a press fit in the socket, and also tapped the hole in the frame to fit. A little ACC helps hold it in place.

Assemble the truck side frames, and then reassemble the entire truck with the exception to the worm shaft. Fit the lineshaft in place and glue or
solder the covers in place. Check the fit and bend the non-geared side frame for proper gear mesh. Pushed down a flat track the lineshaft should
rotate correctly with no binds and the truck should coast an inch or two when released. When you are satisfied, disassemble the truck, clean it and
reassemble with the worm shaft, washers, pickups and everything including lube. With any luck you will not have to dissemble it again. Remember, you will need one front truck and one rear truck, and there are differences in which lineshaft is used.

At this point I like to use power to the truck to check for tight spots and a pre-assembly break in. Put a U-joint cup on the truck (this will be needed
anyway). I prefer to use a Grant Line 2020 motor with 59:1 built in gearing for this as it will run on 9 ma freely. I have a wire fixed across the shaft so it will fit in the universal and run it while watching the current draw. About 10 minutes each way will usually smooth out the running and the current draw will remain steady. This finishes the trucks, and I had spent about 10 to 15 hours on each truck to get here.

Check your transfer case gears under a magnifying glass and clean up all flash and burrs. Assemble with grease, and apply power to smooth it out.
This is as far as you can go with the power train until you have a frame to assemble it on.

One note about selecting a prototype; the wheelbase of the NWSL trucks is 48″. This is long for anything under 16 tons and really more appropriate for 20
to 25 tons. Also the longer the distance from truck center to truck center the tighter minimum radius required. This is due to the four U-joints and sliding shafts on the line shaft binding up. The longer the distance, the longer you can make the sliding shafts without having the halves separate.

If you are building the Keystone Shay, just follow the instructions from NWSL and Keystone as to where to cut, drill and tap. I made my frame/deck
from two pieces of half-hard brass stock plus some c-channel to simulate the I-beam frame. The first was .016 thick cut 6’6″ wide by 29′ 6″ long. Under
this I sweat soldered an .032″ by 3′ by 29’6″ offset 6″ on centerline, and added on each side a c-channel 6″ high. Eventually end beams and coupler mounting blocks were added and the deck cover with 2″x12″ stained basswood strips. The end beams were covered with 4″x24″ strips. All this came after the mechanicals were working properly. The soldering for this was done with an alcohol torch. (I also used a Propane torch, a mini Butane torch, resistance soldering tweezers, and two different dual wattage soldering irons [15/30 and 100/150].)

I drilled and tapped the frame at 18′ centers for the kingpin mounts, then cut out for the Shay engine at the spot called for on the prototype. The last step was cutting the hole for the transfer gear case. This was slightly behind center as that was where it would be best hidden by the T-boiler. At this time I mounted the trucks, gear tower and electric motor, made up the Cardan shafts for the power train and wired the pickups. With some weight taped over the front truck it was time to put it on the track and break it in. I ran it around an oval made from Atlas 19″ radius snap track, and actually used a 1520 Micro-Mo with a 6.41:1 gearhead until I was satisfied with the performance and the thrill wore off. I tried several motors until settling on the 1016 as the best for prototypical speeds and concealability. The 1520 would have required a wood load as high as the cab roof, and the Grant Line gave a top speed of .5 mph.

The Shay engine was assembled from a Keystone kit, (it is available separately), and modified. I did not cut the crankshaft but added some thin
brass wire on the throw side. With wire rods attached the rods jiggle and seem to be moving. The engine mount was filed so the bottom tilted in at a
prototypical angle and mounted with screws so it is removable.

The next part is tedious and time consuming. It is making the U-joints and sliding shafts for the connection between the trucks and the Shay engine. I
don’t trust white metal parts for this as I suspect they will not last. They are made from 1/32″ brass rod, 1/8″, 1/16″ and 3/32″ brass tube, 1/32″ square brass rod, 1/16″ and 3/32″ square brass tube. You will need four U-joints, so the place to start is with the rings. These are 1/8″ round brass tube, cross drilled with four holes at 90 intervals. The best way to make these is to drill then cut to size. Find either a square tube or a C channel that will allow the tube to be a press fit. Square tube is the best as it usually has a slight depression down the center of each side which will center your drill. Channel usually has sides just slightly less than half the width, so after drilling through a wire placed in the holes and resting on the sides will allow a 90 interval. Drill #76 and use an.020″ wire for the pivots.

Each yoke will be somewhat different. These should be built one at a time and fitted to the U-joint as built. The yokes attached to the truck line shafts are made from 3/32″ tube, drilled and ears filed out, making the ears as narrow as possible. Cut a short as possible and solder to a 1/16″ tube. Cut short and ream for a press fit on the line shaft. Assemble to the ring using two pieces of .020″ wire. A little solder or ACC will hold them in place. The other yoke is made of 3/32″ square tube, drilled and cut short. Solder it on to a 1/16″ square tube cut to fit the distance to the crankshaft U-joint, allowing for the pivoting of the truck. The yokes joined to the crankshaft are make the same way as the lineshaft ones, adjusting to fit the crankshaft. Since my crankshaft was made of 1/16″ wire, I only needed the 3/32″ tube. My sliding shaft yokes are 3/32″ square tube, reduced to 1/16″ and, on the front a 1/32″ solid square rod, cut to fit. In the rear I used 1/32″ round rod filed to fit in the 1/16″ square tube from the truck so that it would rotate without binding. This was to eliminate any mechanical kickback from the truck gears.

Ok, this finishes all the mechanicals. When you break it in, be sure to not only run it in both directions, but with the engine side both inside and
outside the curves. You will find, most likely, a difference in the minimum radius it will go around depending which side is inside.

The superstructure is really only cosmetic, for show. All you really need is sufficient weight to allow for maximum traction. It can be built in many ways from almost any material. If there is interest, I will be happy to provide information on scratch building this also.

Scratchbuilding a Shay, part II


I haven’t forgotten you. Here is part two on scratch building a Shay. Before I get into building the
superstructure, I want to make a few notes about motor and gears.

As you have probably guessed by now, my motor of choice is the Micro-mo. These are precision instrument motors with an extremely low current draw. They are available in a number of sizes and combined with the slip-on gearheads offer an easy, although expensive, way of custom tailoring your locomotive speed. One note of caution for those of you using or contemplating using them. They do not like AC pulses. This will destroy them in a short time. Throttles like the TAT III and TATIV used AC pulsing for both slow running and momentum effects. The Micro-mo and similar motors are happiest on pure, filtered DC, and if you must use pulse (not need in my opinion) use square wave DC pulses such as produced by a LM555 timing circuit.
Data spec sheets for these motors can be downloaded from www.micromo.com.

Many people mount these motors using Silicon Caulk compound, but I prefer to use a rigid mount and ACC. Before fastening them down I adjust for minimum current draw by blocking the loco up with drivers turning free. I try to always use some form of coupling between the motor/gearhead and the rest of the geartrain, even if nothing more than a wire soldered to the gearhead shaft (at right angle) and a cup on the gear train. This allows bind free operation with a less than perfect alignment.

As I noted before, on a model locomotive, unlike a real one, the superstructure covers the mechanism and goes for the ride. It should be reasonably accurate, look good and have a detail level that you are satisfied with. On my Shay I left out the cab steps as they have a tendency to break off and their absence is not noticeable. I did include a toolbox, steam fire pump and hose reel on the deck.

I have been asked about plans. Shays were pretty much assembled to order from off the shelf components. The railroad got to specify the length, width, and weight, number of cylinders, fuel, and other details like coupler height (apparently loggers and miners each had their own ideas as to what should be standard). Over the years SL&NG Gazette has printed a number of plans for 15 to 20 ton Shays by Al Armitage. NWSL, in their power kit, has a
side view of a 20 Ton model, and MDC not only has their kit but also prints several books about logging and Shays. Gilpin Gold Tram has plans of #s 2, 3, and 5, and photos of all five locos. As #s 1 & 2 went to the Silver City, Pinos Altos and Mongalon they would work for this too.

They Felled the Redwoods has a number of useful photos, and The Crookedest Railroad in the World not only has plans for Shays but a Heisler and several interesting special purpose cars. Do not forget the useful Titans of the Timber. My favorite is long out of print. It is a 1965(?) Kemtron catalog and manual for their 36 ton Shay. It has drawings of most of the parts, articles by Al Armitage, Sheldon Schwedler, and Dan Ranger. Also are plans for
several 36 ton models, and a 10 Ton by Dan Ranger. Very helpful is a page of stacks, domes, cabs and boilers showing the years they were in use. The boilers also show intake and exhaust layouts. If memory serves correctly the predecessor to Gazette, Finelines also printed several Shay features.

Superstructures are much easier to build then mechanisms, and are a good way to get into scratch building. Just use an existing N scale mechanism and go to work.
Materials can be brass, plastic, wood, tin and even cardboard. Many a prizewinner in the 1950′s was built from laminated Strathmore Board, and they would hold their own with todays models. Jack Alexander is the name that comes to mind. Mel Thornborough (sp) built many models with only hand tools, turning boilers, stacks and domes, etc. with a hand Breast Drill mounted in a vice and files to cut with. Lacking a lathe we can use a 1/4″ or 3/8″ electric
drill in the same way. Parts can be laminated if they cant be turned.

You have a variety of sources for purchasing parts now, and can add all the detail you want. No one, short of the NMRA contest boards, says you get more credit for making everything. It is your railroad, build it the way you want to.

My tools consist of the following:

  • a home built small lathe (not built by me)
  • a 1/4″ power drill
  • a modelmakers drill press (#0 Jacobs Chuck)
  • a Flex-Shaft Dremell hand tool
  • a 100/150 watt soldering gun
  • a 15/30 watt soldering iron
  • a large Propane torch
  • an Alcohol torch
  • a Butane torch
  • a resistance soldering unit with tweezers
  • assorted drills (1/4″ to #80)
  • assorted files
  • knives
  • small screwdrivers
  • taps and dies (more taps than dies)
  • assorted hand tools

This is a fairly extensive list, but I have been building models since I was 7 and am now 64. You do not need anywhere this much to build. The minimum are knives, files, a good drill, pinvice, screwdrivers, SCALE RULE, and soldering equipment

This got longer than I expected so I will go into building techniques in the next part, in a few days.

Scratchbuilding a Shay, part III


As I mentioned before the superstructure just goes along for the ride, and hides the working gear. But, it is the only part of your work that the vast
majority of people will see. You want it to look good and be accurate. Sometimes the last may be sacrificed so that the works will fit. Some of you may even remember Lonnie Shay’s Dyn’ Glory #1 with its 16′ high wood load to cover a micro-mo motor.

I always start building with the boiler. The straight boiler is the easiest, with the T-boiler a close second. I have always had trouble with the wagon top boiler that changes diameters along the way. If I need one of these I try to find one I can get from another model, and kitbash. The straight boiler can be turned from solid brass stock, and can include the stepdown for the smokebox. If you are good you can even include the boiler bands. You do not need a lathe to turn this, a 3/8″ electric drill clamped to the bench and files are the bare minimum. A steady rest for the files or scrapers will definitely help. I turned mine on a homemade lathe (made by someone else) and included the hint of a smokebox door.

If this seems too much for you to try, just use telescoping brass tubing. Start with the smokebox, slip on the next size for the main lagged boiler
and cut thin bands for the banding, or build them from thin brass stock strips such as sold by Russ Simpson. Use a boiler front from an N scale
loco (the Bachman 0-4-0 is about right). Oh yes, solder everything together before attaching the plastic boiler front. You can even build a boiler from
Evergreen Plastic tubing. Wrap the tube with .010 stock for the lagging and add bands. This last method will produce a very light boiler and for that
reason is not recommended. If you really are a glutton for hard work roll your boiler, etc. from shim brass. If you can do this, you don’t need
instructions.

A T-boiler is just a straight boiler with a brass rod or capped tube at a right angle to the main boiler. File the end of your boiler to fit the
round shape of the T (actually the smokebox) and solder. Wrap your boiler with wet tissue or coat with a paste of yellow ochre to keep the already
completed joints from de-soldering. I used a hollow tube for this part with a turned boiler for weight. The hollow tube let the transfer gearcase slip
up inside and hide. Sand dome, headlights, stack, bell, whistle and pop valves are available from Cal Scale, Precision Scale, Keystone Locomotive
Works (try their logging junk pack), and Kemtron (still showing up in a few hobby shops and swap meets).

My loco has a Keystone sand dome, Cal scale bell and front headlight, Kemtron headlight bracket, turned stack with a base from the scrap box.
Tool box is from Kemtron (Precision has it now) and a Cal Scale fire pump and hose reel which hides the lack of detail on the boiler front. Don’t
forget hand rails. Also use soft brass wire for the exhaust manifold(s) and the sand lines.

My cab was made from a left-over MDC Shay cab (Sn2 project) by cutting and narrowing the width to fit. A scrap or two of plastic was formed into a
hatch to help hide the joint and plastic filler and sanding took care of most of the rest. Cabs can also be built from scratch from brass sheet,
plastic sheet ans strips or wood stock. Just remember the right side has the cut out for the Shay engine, and has a shield extending into the cab.

The water tank and fuel bunker is just a wrapper with a top and enough of a bottom to allow mounting to the deck. I made mine of plastic due the close
clearances with the motor, and fears of shorts. It has a sheet top, a filler tube from scrap, and railing for the wood made from HO plastic ladder
stock. You can use wood or coal for fuel in this type of bunker. Oil calls for a square tank fitted in the fuel space and extending back over the water
tank. A rear headlight looks good mounted on the tank. Rear sand tanks usually were fitted on the rear deck and were in the shape of flattened
cones. Make these from whatever scrap material you have on hand.

Add whatever level of details you feel comfortable with, also remember that most of these locos were loaded with junk, chains, retailers, jacks, tools
etc. Paint and weather to suit.

Shays were usually assembled to order from off the shelf components, (kit bashed?) And the details of dome ans stack shapes, headlights, etc changed
over a period of time. Study photos but don’t worry about the exact prototype as each loco was an individual one of a kind.

I know that this is only a brief coverage of the topic, there are so many ways of doing things that it is hard to cover them all. Materials are cheep
and you figure the time spent is enjoyable, so don’t settle for less than your best. If you do not like a part, make another. You get better with
practice. If you have specific questions write, but put it on the Mail Car, rather than Email. That way everyone can benifit.

Siles Bazerman

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