Atlas Turntable

Ed,

 

I did the same thing a while back

 

I didn't find anything that said which one goes where, but if you put them in the "cups" where they're suppose to go, look at them to see if they're sticking out the same.  I think that's the way I determined if they were in the correct "cups".

 

I held mine in place by applying some conductive grease then turning the platter back over to install.

 

Here's what the manual says:

 

Warning! - Connecting the turntable motor directly to AC power
can damage it. Please use the supplied rectifier and Twin as
described above.

Use the speed control knob on your power supply to regulate the speed that the
table turns. To best simulate prototype operation, it is suggested that the turning
speed be kept at the lower end of the controller range. Too high of a speed could
disengage the drive belt from the motor assembly (I found under 7.5 vdc works good, I'm using a switchable wall-wart to select the voltage I want). Should this occur, please refer
to the Maintenance section of these instructions.

Powering the Tracks for 3-Rail Operation
The turntable is factory-wired for 3-rail operation. Fig. 3 shows the power connections from the transformer to the table. These connections power the turntable track only.

Each of the turntable storage tracks will require similar connections to the outside
common rails and center rails. It is suggested that each stall track be wired through
an on-off switch, such as the Atlas #205 Connector, for easy power shut off.

If you are using Lionel® T r a i n M a s t e r ® Command Control, ensure that the command base is connected to the common (outer) rails of the turntable track and
every storage track. If you are using strictly command-controlled equipment, it is
not necessary to have the storage tracks powered through an on-off switch.

 

The diagram in the manual shows that the terminal to the left of the motor housing is the outer rails and the terminal to the right of the motor housing is the middle rail.

I had that same problem, I know the feeling of frustration trying to get those bebe sized contacts back in place. Turn it updide down, put a very small amount of vasoline on the contacts to hold them in place while you reattach the table top, then turn it over. Might take a few tries but hopefully the pins stick in the tracks

Its a toy like flimsy drive system that has never been upgraded by Atlas

Mine recently stopped working in one direction. 

Unless I jolt it with 20 volts it just sits there and hums.  I won't go through the work of taking up from the layout until I figure out how to improve the drive.

So, I picked up a used second table on the cheap and I hope to convert to a more robust direct drive when I figure out how to do it.  

Joe 

Thanks to both of you.  Good idea about grease holding the pins, however are they suppose to match up wit the holes from the other side or just make contact wherever it hits.  I don't think I explained myself correctly, but I will give it a whirl after diner.  The motors for these things drive  HO, talk about flimsy.  I afraid to even but my "A" of my 2333 Santa Fe in fear of wrecking the whole thing. I will keep you posted and thanks.

Ed

OK!  You guys did it again.  I inserted the pins using Vaseline and it worked perfectly.  Now I have current running through the middle.  The next issue is I switched it to the manual crank during this time and occasionally the table gets hung up and doesn't do a full i80.  I can push it with my hand, but that is not what I have in mind.  I tried tightening and loosening the screw on the bridge and it helps a little but not a lot.  Before I hook up the power to turn it, I want to make sure it stops correctly at each space.  Any suggestions on how to make it index correctly? Let's make it two for two.

Thanks again,

Eddie, The only way I've ever heard to make it work as intended is to trash the flimsy drive system and replace it with a direct drive..

Should you or anyone on the forum decide to do that,  here's the directions a fellow formite gave me years ago to ugrade it. I sadly forgot who it was.

You may want to copy the directions and photos for future use.

When you're finished I suspect that table will work as good as any on the market. I intend to upgrade my table this way. 

Someone with a little ingenuity probably could make a good side income doing what Atlas should have did years ago selling a ready to install upgrade to those hundreds or more suffering Atlas turntable users in trainland.   

Joe

 

"Strip the unit of all the Atlas electrical components and revert it to the manual hand crank arrangement.

Then the motor assembly is mounted where the hand crank would be, takes over and winds via the small toothed wheel under the crank (see picture)

 

The motor is attached to a small aluminium plate, the only thing that needs a bit of engineering is attaching the small geared wheel to the motor shaft with a small brass boss

 

The result is that the turntable operates as normally including the pause at each siding rail"

 

Ed,

 

Check the gears for ANYTHING that may interfere with the teeth, next do the same for the "cam" that's the underside of the platter.  Make sure there's no loose ballast, molding flash, etc that would bind the operation.  I even put some grease on the "cam" to make it slippery, but that will also be a collecting point for tiny bits of ballast so be careful.  A tiny ballast rock will stop this thing dead in its tracks.

 

Make sure the rubber belt isn't twisted, as a matter of fact, remove the one that came on it and put the spare on if you have one.  Don't use more than 7.5vdc to power the motor.

 

I haven't read this, but IMO the more it's run the better it will perform after it "breaks in".  The "cam" is the indexing cam, that's what makes the TT stop at each stall track.

 

I'm really surprised there has been no commercial upgrade to the drive on the TT, the "cam" IMO works fine but the drive could be made beefier.

Thanks for both suggestions.  I have enough odd ball motors in the house to try replacing the existing system, but first I'll try to clean it.  It seems a tad easier.  I will post my remarks. Actually, since I fixed the turntable from an earlier suggestion and went back to electric power it seems to be indexing better.  The slower I run it the better it gets.  But, I  don't like how long it takes to position it correctly, but it does seem to work.

Ed

Glad to hear it's working Ed!

 

I didn't look too long at the cam underneath, but I wonder if the slots for the stalls that aren't used could be blanked over somehow to bypass them?  Stopping at every stall position does make things slow.  I only use 4 of the positions.

Hi Eddie.  I was given one that I spent considerable timeon and now have it running very smoothly in both directions.  I took it apart several times and after seeing the problem with reassembling with the two contacts staying in I did a search on the forum and read everything I could on the Atlas TT.   After determining that one of the contact pockets in slightly deeper than the other, I reassembled it upside down using 5 small clamps to hold it together.  I also applied a dab of CA to the small nut which holds the two halves together.

I also applied a small amount of super lube to the plastic gears and the brass piece of the motor assembly.  BTW, somewhere in the archives someone listed the replacement belt that you can use from one of the big box stores plumbing departments.

Then the light bulb finally lit up in my head!  I noticed that on one end of the TT tracks had a fine amount of white on the end.  I put back the manual crank and by turning real slow I saw where the TTtrack was hitting the raised box (for lack of the proper nome of them) that separates each track location.  I hit the end of the tracks with a dremmel and ground down just enough so they cleared the box.  It now runs smoothly in both directions, even at a speed of 10 VDC.

For an inexpensive TT I find the indexing system pretty ingenious the way the cog on the gear moves the TT to the next position and then moves out of the slot causing the table to stay at the position until the cog rotates into the next slot and moves the table to the next position.  Remember, this TT will require some maintenance as all of our (toy) trains do.  With this in mind, I installed mine to be removed, with all track leading to it no longer than 6 inches.

Sorry to be so lengthy, but I hope this helps.

John

John,

Great information. One thing I did notice and did nothing about is the fact the contact pins are not the same length.  That coincides with your comment that one of the contact pockets is deeper then the other. Also, I will get the Dremel out to do some sanding.  This evening I took my wife into the train room to show her how nicely the TT was working.  Little did I know I would be taking it apart again. 

All you folks on OGR are the greatest.  I guess that's why we call it "The Greatest Hobby in the World".

Thanks again to everyone and I will continue updates. 

Ed

 

Eddie, glad I could help.  Don't forget to glue that bottom nut to make reassembly easier.

How does one re-install a brand new belt, rubber band, O ring to the pulleys?  How does it come apart in order for belt drive to be replaced?

John,

Take the shed off the motor cover, then remove the 2 or 3 small screws covering the gears.  Note the position of the top gear spindle which is held in place by the cover you just removed.  You should see the two pulleys, one to the motor and one to the gear box.

Before you reassemble place the manual crank on the top gear and rotate it by hand to see it hangs up anywhere.  Mine did and I had to adjust the TT track so it didn't hit any of the pylons.  When it hangs up the belt sometimes spins and this is what causes it to wear out.  Good luck.

John

Thank you!  Belt: Danco #33 "O" ring installed.  It works like a charm, perfect!!!  The Atlas Model Railroad Company should strongly consider installing this O ring directly from the factory to eliminate the stream of complaints.  The factory installed band is a square shape and not as thick.  The #33 O ring is a better shape for this pulley system and better made.