Bidding on HO Trains - Rivarossi 4-6-2 Light Pacific

[articulatedgeared01]

Mon 10-29-18 4:25 p.m.

I like the Rivarossi 4-6-2 Light Pacifics.  They have spoke-type drivers and 4-wheel trucks on the tender.  I have repaired a good number of them.  This post  covers some issues which might be helpful before you bid and buy.  In good shape, they are worth about $25 to $45.

1) Design Flaw - The rear driver on the light pacifics (closest to the cab) has a brass gear and is the operated through gearing by the motor in the loco cab.  The rear driver has to power the other two forward drivers.   Both the forward driver and the rear driver have traction tires on one side.  All of the drivers have light plastic spokes.  The problem is that the design is not balanced (that is, the motor-driven driver is not in the middle between the other two drivers).  This means that there are very large torsional (twisting) loads on the rear driver wheels / axles / crank pins.  If the locomotive is loaded up with lots of cars to pull, the loads on the wheels / axles / crank pins go up with each added car.  So the driver wheels / axles can easily go out of quarter (that is, the knurled brass axle can break away from the plastic driver insert).  In addtition, the plastic driver insert can break where crank pin is located.  Breakage of the spokes in the wheels is common.   beakage of the attachment point for the crank pin / brass hex nut - barrel nut where it attaches to the driver is common.  Finding replacement drivers is difficult.

- To be continued - 

[articulatedgeared01]

Mon 10-29-18 4:45 p.m.

- Continued-

1) To prevent failure of the rear driver, keep the number of cars pulled to a minimum.  If the driver wheel fails, it can be rebuilt with tiny tin can strips insreted in place of the plastic spokes.  The tin can strips can be fitted in place carefully and attached with some super glue on the end of a pin.  If driver goes out of quarter, it is necessary to drill a small hole through the brass driver tire, plastic driver insert, and brass axle.  A short pin 1/4-inch long can be pushed in place to key the axles to the plastic driver inserts.  I usually  insert the 1/4-inch long pin and then push it home with another pin.  Then I pull the pusher pin out.  The pin used as a key must not be so long that the brass axle and driver tire are connected.  This will cause the driver to short out.  A drop of super glue on the end of a pin (a small amount of glue) will hold the pin in place in the driver axle.  An NMRA gauge is needed to be sure that the flange-to-flange width on the driver is proper before drilling and pinning the driver.  If driver is a bit out of alignment, it may wobble when operated.  Be careful when using pliers to re-align the driver wheels or breakage can occur.  A drop of super glue on the end of a pin may be applied on the outside of the axle and plastic insert to strengthen the damged driver.

2) Plastic Motor Mount - The plastic motor mount in the later run Rivarossi Light Pacifics was notorious for breaking.  It may break where the screws attach  the motor to the motor mount.  The motor mount may already be broken (or on the way to breaking) when you purchase the loco.  If the loco rattles around in the shipping box (that is, the loco was not splint packaged), the motor mount may break during shipping.  The motor mount can be repaired with a plastic fusion weld.  Alternately, a reinforcing plate can be made with a piece of tin can.  I suggest making the tin can plate about 3/4 inch to 1 inch in diameter so that it picks up both mounting screws.  Use super glue to attach the reinforcing plate to the broken motor mount.  Use small amounts of glue and keep the glue away from the motor shaft and screws / screw threads in the motor case.  It is a good idea to put some lubricant on the motor shaft  / motor case bushing to prevent prevent glue from seeping on to the shaft and locking down the motor.  Caution: Do not loose the Rivarossi motor mounting screws.  If longer screws are used, they can be turned into the armature windings and detroy the motor.

3) Driver Crank Pins - It is important to have small washers between the crank pins and the hex nut in the drivers.  If the washer is missing, the crank pins can back out and jam the mechanism.  The crank pins need to be snug.  Never - Never glue the crank pins in place.

4) Trailing Truck - The plastic structural member likes to break on the rear of the trailing truck.  It can be repaired with a plastic fusion weld.  A "Z"-shaped bracket (fabricated from tin can stock) can also be fabricted and glued to the metal strip in the middle of the trailing truck plastic structural member.  Simply gluing the structural member will not work because the bond area is too small in cross-section.  Pouring on a blob of epoxy on the trailiing truck looks ugly.  

5) Tender Trucks - Check that the tender trucks have the conducting / spring wipers on the trucks.  Also check that the tender wheels and loco driver wheels are clean / bright.

6) Grab Iron on Cab - Make sure that the grab irons are in place on the back of the cab.  If the grab irons are not there, it means that someone may have been experimenting with the "inards" on the loco.

7) Fasteners - Look for missing screws on the bottom of the loco.

😎 Draw Bar Spring - Make sure there is a conducting spring / tang on the drawbar to ensure proper pickup from the tender.

9) Smoke Box Cover - The smoke box covers are easily lost on many Rivarossi models.  The smoke box covers are expensive and hard to find.  I suggest making one from tin can stock with appropriate detail hardware if the smoke box cover is missing.  After Market Smoke Box Covers may be the wrong diameter and detract from the appearance of a steam loco.

10) Modifications - I don't like locos which have been modified - particularly motor swaps.  The inards are generally chopped up and you can't see this with most of the pictures taken of the outside of the loco.

To Be Continued 

[articulatedgeared01]

Mon 10-29-18 5:21 p.m.

Continued 

11) Sun Damage - Many Rivarossi Loco are destroyed because some nit wit displayed them in the train box and left the box out in the sun.  The train box acts like a solar panel and traps heat - particularly on black locos / tenders.  The result is that the loco or  tender shell may distort.  Make sure that you have "good" picutres of BOTH SIDES OF THE LOCO / TENDER.  Watch out when buying train lots.  The locos are not worth much if they have distorted / melted shells.  Melted shells around the cab may also indicate an overheating motor / burned-up motor.

12) Motors - Look to see if the brushes are about flush with the brush carriers on the back of the motor.  If they are brushes are recessed in the brush carriers, it may mean that the loco has experienced high usage and may have considerable wear.  Watch out for rust buckets from humid states.  Watch out for hurricane survivors from Florida, Texas, etc.

13) Wiring - Watch out for modified wiring.  This is a hint that some experimenting has been going on with the loco / tender.

14) Packaging / Shipping  - pilots / draw bars / cabs can easily be broken / bent during shipping if splint packaging is not used.  The original AHM (blue-yellow) long boxes had plastic inserts.  Many inserts have aged and become brittle since the 1960's.  If the loco is dropped on end / tossed / shipped on end, the loco can smash through the thin / brittle plastic train box liner.  Then all of the griping between byer and seller will ensue.  It helps to take loco out of the original box and ship it with bubble pack and a splint.  

15) Axle Wear - The Rivarossi locos have brass axles which run in steel frames.  The steel frames can wear grooves in the brass axles.  When this happens, the locos may jam during operation.  You cannot see this kind of wear with pictures taken on ebay.  Only tear-down and inspection can confirm if this problem exists.

Regards,

ag01

[articulatedgeared01]

Mon 10-29-18 9:48 p.m.

I goofed !

I discussed using a tin can plate 3/4 inch to 1 inch in diameter to repair a broken motor mount on the loco.  Such a disk will obstruct the cooling holes in the motor and may cause the motor to overheat and fail.  Instead of using a disk, separte tin can straps might be used instead.  This will allow the cooling holes to remain open on the front side (pilot end) of the loco.

On the Rivarossi Light Pacific I repaired this evening, I used a plastic fusion weld to repair the broken motor mount.  I used black zip tie material as filler rod for the plastic fusion weld.  This plastic smells the same as the Riarossi shell plastic.  The motor mount has little forks which stick up and permit retention with short threaded fasteners (machine screws).  If you like, the melted plastic can be used to create a bridge across the top of the fork-type retaining features.  Caution: Use of a soldering iron (for example, a Weller 8200N solder gun with a flattened copper tip) can dump quite a bit of heat into the motor mount.  Be careful not to get two much heat around the loco footboards on side of the loco (next to the motor mount).  It can cause distortion of the footboards.

A final problem is the electrical pick-up pins on the chassis next to the front and rear driver wheels.  Sometimes the pins do not touch the underside of the cover plate which holds the drivers in place.  Then the loco may not run or will run intermittently.  What to do?

Cut out a piece of tin can stock abut 1/16- to 3/32-inch wide using a pair of scissors.  The strip will curl up, so flatten it out.  Scrape all the coatng off both sides of the tin can strip (to make it conductive).  Cut off a section of strip about 3/4 inch long and bend it into a "V" shape in the middle (3/8 inch).  Right above the pick-up pin location (on the cover plate) scrap away the blackened coating to bare shiney metal (steel).  Put a drop of super glue inthe middle of the cover plate and place the end of the "V" - shaped strip in the glue.  This will allow part of the strip (electrically conductive) to touch the outer part of the cover plate (electrically conductive).  You will note that the other side of the "V" - shaped strip will be bent down slightly (on the underside of the cover plate) toward the pick-up pin.  Now install the screws which hold the cover plate in place.  The "V"-shaped strip will touch the pick-up pin and complete the circuit, which is what you want.     

Regards,

ag01

[taz-of-boyds]

ag01,

Thanks for the posts, I don't work in HO, but get some useful info just the same.  Some diagrams or photos in some cases might be handy to show what you are describing.

Thanks,

Charls Sloane

[articulatedgeared01]

Sat 12-8-18 9:00 p.m.

Hi:

I do not have the capability to provide photos or diagrams.  However, if you require additonal information, I can try to explain in more detail or with a different methodology some of the previously provided information.

Regards,

ag01