Wednesday, June 3, 2020

Bachmann pancake motor GP50 and Life-Like pancake motor GP38-2 Multiple Unit Build

Bachmann High Nose GP50 pancake motor
Life-Like High Nose GP38-2 pancake motor
Multiple Unit Build

I've got these 2 locomotives that I found at train shows.  They both have the infamous and notorious pancake motors.  A few years ago I airbrushed them with Rustoleum Gloss Red Enamel.  The paint jobs are actually pretty good, but did take weeks to fully cure.  I also put the decals on and number boards.  Then they sat in the junk pile for about 5 years.

I got the idea that I could use a 2 pin connector and make a connection between the two locomotives so that they would share power.  The reason is that they have plastic front wheels with traction tire and only get power from the rear truck.  Yes I could have replaced the wheels and made it all-wheel pickup, but I've lately been trying to think of ways to improve the original system without investing into replacement parts.

I rebuilt the motors to better than new performance.  In fact, the motors, despite being damaged and beat up, have come back to life in the most amazing way.  I've always believed in the pancake motor concept because it's proven itself in slot car racing.  The motors in DVD and CD-ROM drives are pancake motors with a better enclosure and more modern cores, but they are still pancake motors.  I'll probably be using one of those motors from an old DVD drive on a Bachmann steam engine that I've got sitting in the deadline.

So the concept of this operation is to make a PC board that collects power from the pickup truck.  Then power is routed to the motor.  But, a set of wires with a 2 pin quick connector will also be on that PC board.  The male connector will be on the outside of one of the locomotives and the female with a bit of the wire leads will be on the other.  When connected, the 2 locomotives will be sharing power pickup from 2 trucks instead of 1 truck each.

So let's see where this takes us....

Clean the wheels, polish them and paint the ends if you're going to do that now.  Clean any paint off the part that touches the rail.  Coat the back and tread area with Oxgard - it will stay greasy for a couple weeks then turn to a film.

Wipe a paper thin layer of red lithium high temp brake grease - which you get at any auto parts store in a little tub that will last decades - into the sockets that hold the axles.  No more than a paper thin layer and no excess.

You will lay the wheels into the centerpiece after the wipers are installed - but do not put the side frames on.  When you get to the phosphor bronze wire step, carefully set it upright without the sideframes on and with the wheels in place.

Rebuilding the power pickup trucks is one of the more difficult challenges.  The idea is to keep the copper wipers exactly as they are built.  They need to be cleaned with new black and red 32 awg silicone wire soldered to them.  Then they must be coated with Oxgard.  The new leads are threaded through the existing holes like usual.  But, before doing any of that we need to make a modification for the new parts we're going to make.  Look carefully at the truck and you will see a small hole where the wire gets threaded into the center so it can go up through the frame.  You will need to take a 1/16" drill bit and make a second hole that mirrors the one on the other side.  You will be drilling 2 holes, 1 on each side so that when you are done you will have holes that match.  This is super simple but hard to describe, there will be pictures later.  Look at the truck and see the holes that it came with are drilled near the axle socket.  You will make 2 new holes in the same way near the other socket - like a mirror.

Now you can install the copper wipers and thread the wire - red on one side, black on the other.  This wire goes through the hole that was factory made - right hand hole when you are looking at it laying on its side.

You will need a tube of phosphor bronze wire for the next step.  My goto wire for this is .0125 phosphor bronze from Tichy.  You will need to cut 2 pieces that are long enough to span the tops of the wheels on each side, but not so long that the sideframe can't be put back on.  Lay this piece on top of the wheels and mark a spot just to the right of the hole we drilled earlier.  Now tin this spot with solder and solder a red wire to one piece and a black wire to the other.

Next thread the wires through the holes we made - make sure the red is on the red side and the black is on the black side.  You can't do this wrong because the center piece of the truck will fit either way, it's totally the same.  Just get all the wires of one color on the same sides.

Pull the electric wire tight enough to keep the bronze wire touching the tops of the wheels.  At this point you will probably need a drop of super glue to hold the electric wire tight.  When you have everything they way you like it, put the side frames back on.

Saturday, May 23, 2020

Brass Tenshodo SD24 Total Rebuild

Rebuilding a brass Tenshodo SD24

Part 1

The HO scale SD24 brass diesel locomotive by Tenshodo is a difficult beast to tame.  The goal of this project is to rebuild it and keep as much of the original mechanism as possible - but not the motor.  This locomotive is going to be powered by a rare earth super strong magnet 24 volt motor.

There are 3 mechanical challenges to overcome.  First is the linkage from the motor to the gear tower.  The original design uses a rubber hose.  This is a totally sound concept and the original hose can be replaced by a slightly more flexible silicone hose.  The silicone hose is very cheap and a single roll will probably last a lifetime.  The shaft on the gear tower is one size bigger that the shaft on the motor, but the hose does not have a problem with that.  If you have a locomotive with a worn out hose, the size I used has an outside diameter of 4mm and inside of 1mm.  I also tried a hose with 3mm outside diameter and found it to be too flexible, but still usable.  There is another option and that is to use standard splines and couplings like those found in an Athearn blue box locomotive.  The motor has a much smaller shaft than the Athearn, but since I can 3D print these parts that shouldn't be a problem.  We'll see if it's necessary after everything else is mechanically sound.

The second challenge is the power pickup.  The trucks pickup power from one side only - and then only from 2 of the 3 axles.  The middle axle floats and doesn't contribute to the pickup all the time.  It's not a dead axle, but it's not normally load bearing in order to prevent skidding type derailments.  With little to no weight on it most of the time it shouldn't be considered a reliable source of power, but....  The first upgrade that I am trying is the phosphor bronze wire trick.  If I can use a piece of phosphor bronze wire that wipes the top of all 3 wheels and then use a wire to my power collection board the reliability will improve dramatically.  If that works, it may be possible do it to the insulated side wheels giving me power pickup from all wheels - that would be huge.

Challenge 3 is the drive shaft connecting the 2 trucks on the underside.  This shaft tends to disconnect frequently.  I have successfully test a small silicone hose sleeve on the end that gives the trouble.  This seems to work so far, but the locomotive has yet to complete the obstacle course of tight switches and curves that I setup.  The goal here is to negotiate 18" radius curves and #4 crossovers without derailing.

The first step in the whole procedure is to make sure the trucks have reliable movement.  Gear binding seems to be a serious problem.  One of the worm gears needed sharpening on the drive shaft on the front truck so far, but is still suspect.  One of the axle gears had broken loose.  A single drop of super glue fixed that gear in place very tight, but now we have to see if the tolerance between axle and worm will mesh....

Several hours later.... the binding gear problem was solved.  The gear in question was examined much more closelier, yes closelier.  The gear was split.  To remove it the axle was heated with the big soldering gun and the insulated wheel comes right off.  My first thought was to replace it.  I found a plastic replacement that I could have used if I put one on each geared axle in both trucks.  Like I've said many times, shaft sizes and gears are not special.  When a gear is cut, it's cut using a tool that is a standard size.  The gear cutting set is like a machinist drill bit set in that the sizes are all indexed.  This is why you can almost always find a matching gear to anything that needs it, as long as you know where to look.  For now, I've just removed the old gear and someday I'll run across another wheelset that I can replace that axle.  Unless this project turns out to be much better than expected - then I'll replace all 4 gears from my plastic replacements.

Tomorrow's job will be seeing how smooth I can get it to run before I add the extra power pickup.

The phosphor bronze wire totally did the job.  The multimeter shows full voltage through the wires.  Now that power available, we can test it.  On the road test first we checked to see if the hoses used on the drive shafts both topside and underneath would hold.  The good news is that they work so well that they will be retained.  The hoses have done an excellent job.  The crossover test was successful and without difficulty we went over a large crossover that has long unpowered frogs.  We were able to make several times without derailing or stalling.  Next we tried a string of #4 switches that are from a mix of manufacturers.  Rail is brass, yellow brass, steel, nickel silver and we made it through without stalls or derailments.  Then we moved on to the 18" radius test and that was no problem.  Feeling extra brave, we went through a spaghetti bowl of very sharp turnouts and then down to the 15" radius that crosses open space over a concrete floor.  We went through the 15" with some grinding sounds, but stayed on the track both fast and slow.  I'm calling this rebuild a success so far.

Really digging into the locomotive and its inner workings has helped me step up my game to a new level.  For a couple of years I've considered this SD24 a piece of junk - and for good reason.  I haven't been able to find any good comments from people who have them or any stories of rebuilding them.  I know they are out there and hope this story will bring out other information.  Now that the locomotive is in very good working condition I can move into paint and decals.  I have something exciting in mind....

Now time for some pictures....

And that's a wrap.

Sunday, November 17, 2019

1969 Majorette Saviem Fuel Truck makeover

I had an old 1969 Saviem fuel truck by Majorette.   The frame was bent and the paint was in rough shape.  All the axles were also bent pretty bad.  So let's see what can be sone...

 Rivet removal with a 4 flute end mill in a milling machine

After black primer, Jokaero Orange with a coating of clear gloss.
 Armypainter Kraken Skin fenders and interior walls followed by Liquid Talent aka...Agrax Earthshade

Some decals I whipped up for another project were perfect, also some lining with a silver sharpie pen.

I like it.

Friday, November 1, 2019

A.C. Gilbert HO scale Alco Diesel DL-600

On the workbench we have a 1957 A.C. Gilbert Alco Diesel in HO scale.

These are the before pictures for this rebuild.  I don't collect them, I find them, fix them and run them.  This locomotive has excellent potential and for being 62 years old it was in very good shape.  It was missing a drive shaft, which was easy to fabricate.  The mechanism is similar to Tenshodo brass.  The plan is to replace the fully functional open frame Pittman motor with a new 24 volt rare earth magnet motor.  The wires will be replaced with silicone wiring.  Since the motor will be isolated, there is no reason this can't be an excellent DCC locomotive.  There is also plenty of space to add big sound to this build.

We'll see what happens... I have yet to see where anyone has rebuilt one of these, though I'm sure they're out there somewhere....

More Athearn Blue Box DD40 rebuild photos

Some more photos of the Athearn Blue Box DD40 rebuilds that are on the workbench....

AHM FM C-Liner Rebuild

The AHM FM C-Liner Rebuild Project

The C-Liner project is coming along nicely.  The much maligned from pilot was cut off and replaced with some tin I bent from an oyster tin.

The B unit is a dummy, but I've made it to pickup power which I plan to distribute through tiny 2 pin connectors to the 2 A units making a lash up that gets power from all 3 units together making for a super reliable set up.  Picking up power from many wheels over a long distance should insure that it never stalls from lack of power.

1976 TYCO Midnight Special

1976 TYCO Midnight Special 50th Anniversary Shark Nose Locomotive

The Alco RF-16 Shark Nose Diesel Locomotive built from 1950-1953 was a 1600 horsepower engine.

TYCO came out with a Shark Nose called the Midnight Special for the 50th Anniversary in 1976.

I rebuilt this model and dressed it up a bit to see how it might look.  Turned out pretty good, runs decent and is equipped with LED lighting.