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Tortoise Re-Conditioning: Pro-Tip Journals/Blogs
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Super User 708 posts Paul Mac espeelark Super User 708 posts
Paul Mac espeelark

So, on various pages of my "SP Lordsburg Sub - Construction" blog, I posted a couple of entries about how I went about reconditioning a batch of used Tortoise switch machines that I had picked up ...

Tortoise Re-Conditioning
https://forum.mrhmag.com/post/sp-lordsburg-sub-construction-12214626?pid=1331373992

Tortoise Re-Conditioning - round 2
https://forum.mrhmag.com/post/sp-lordsburg-sub-construction-12214626?pid=1331379969

We installed a bunch of them, wired them up and then my Chief Electrical Engineer (on loan from the Cincinnati West) advised that he was getting an open circuit on some of them when he put power to them. We wound up removing and replacing ~six of them!   #&%*@$!(}[$^#%@!

After I opened them up, I found the problem to be that a pair of the copper fingers/wipers were bent out of position and not making contact with the circuit board. Gee, I wonder how that happened!? I had a fleeting thought that perhaps there was sabotage at foot here knowing that my work crew also work on the Cincinnati West - and he pays them with pizza. Alas, I was the only one who worked on those switch machines when the were open so we know where the blame squarely lies.

Here's a photo showing the issue. Look at the pair of copper fingers/wipers to the right. You can clearly see the air-gap between it and the circuit board trace.

0-%20MRH.jpg 

Here's another shot. You can see the fingers/wipers to the left are not in the same plane as those to the right.

0-%20MRH.jpg 

After I gently bent the fingers/wipers back into place and re-assembled the tortoise, they checked out fine electrically in both thrown positions.

And now we arrive at the Pro-Tip: double-check EVERYTHING when you take something apart. Adjacencies to what you were working on may have inadvertently gotten whacked and you didn't realize it. Or, since these switch-machines were used to begin with, perhaps they came into my possession this way and I just never noticed it.

Paul Mac

Modeling the SP in Ohio                                                                                  "Bad is never good until worse happens"
https://model-railroad-hobbyist.com/node/38537
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s_brown Regular poster 160 posts
s_brown

Another solution

I have also CA'd some micro switches to the bodies of my Tortoise Switch Machines as I never really liked the sliding fingers, if you do have a failure of the mushroom nubs and the copper slider goes the wrong way could create a fairly large problem for me as I switch frog polarity with these micro switches.

Whilst I only needed one for this purpose, I have attached two to most switch machines for future use (or even failure replacement).

What this also means I have up to 4 different electrical switch options per switch machine too.

Ironically I've been inside a couple of the cobolt motors I have for exactly same problem as you've seen with the tortoise. I also dont like the way these mount the motor to the PCB and then use caulk or something similar to "attach/stabilise" the motor casings to the plastic switch machine casing. I wont be buying these again as I dont think they are as reliable as tortoise motors

Simon
Melbourne Australia
Modeling the UP - steam to diesel 
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railandsail Prolific poster 8,800 posts
railandsail

Interesting,...as I have a

Interesting,...as I have a whole bunch of these Tortoise machines I will need to sell soon,...both new and used. It will be nice to tell the buyer where he might look to repair any of the 'faulty ones'

(I have most all my turnouts either hand controlled, or manual rod controlled)

Brian

1) First Ideas: Help Designing Dbl-Deck Plan in Dedicated Shed
2) Next Idea: Another Interesting Trackplan to Consider
3) Final Plan: Trans-Continental Connector
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Paul Mac espeelark Super User 708 posts
Paul Mac espeelark
So I recently acquired another bunch of used Tortoise switch machines and I set about re-conditioning them as I had previously done. They all get electrically checked and every single one of them gets opened up to upgrade how the copper wipers are attached. I've switched from using two-part epoxy to using small, metric M1.4 self-tapping screws. I use a chisel bladed X-acto to cut off the plastic mushroom nubs, then drill a #60 pilot hole where each of the nubs had been, then re-attach using the screws. Here's what that looks like after the mod:
MRH 220224 03.jpg

I made a little fixture out of a paint-stirring stick to allow the actuation arm to sit flat while doing surgery on it. It's two thicknesses of paint stick glued together with two wholes drilled through to accommodate the sticky-outie parts on each end of the arm.

I also noticed that some of the Tortoise's "clicked" when being actuated. I looked closely at each of the black-plastic gearsets and observed debris in the teeth. Use a pointy tool (aka tooth-pick) to remove the debris and re-assemble. Volia the clickety-click disappeared!
MRH 220224 04.jpg

While inside, I also use a cotton swab dampened with contact cleaner/lubricant to clean the PC board traces before re-assembling.

Paul Mac

Modeling the SP in Ohio                                                                                  "Bad is never good until worse happens"
https://model-railroad-hobbyist.com/node/38537
Read my Blog Index here
 
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JC Shall Prolific poster 1,493 posts
JC Shall
Tortoise Switch Machine Inspection and Lubrication

I received an email from Circuitron back in  June 2013 with these tips to recondition Tortoises.  Perhaps this will be helpful as a general guide, and will mesh with the posts above.  Note:  do this only for your older Tortoises as damaging the label covering some of the case screws may void your warranty.

The TORTOISE is lubricated at the time of assembly with a small amount of LaBelle 102 heavy gear oil, or equiv. This is a sticky oil that is totally synthetic. To my knowledge, it has no tendency to dry out or gum up. However, considering the age of many of the machines, it might be prudent to open them up and have a look. There are 5 screws holding the case halves together with one of them in the center under the label.

Once you have the case separated, inspect the stem gear (the one going through the circuit board) small end axle pocket in the case halves for wear. Any signs of green particles or elongation of the axle pocket is not good. I would not recommend putting that TORTOISE in service. We can sell you new cases.

If that wear area looks good, remove the arm with the finger contacts on it. Inspect the circuit board for wear where the contacts were riding. As long as there is still copper and it is not worn through, that should be fine. The plating wears off quickly but the copper lasts a long time. Inspect the heat staking of the contacts to the arm. There should be two button rivets on each arm, they should look fully formed and the contact should not be loose and move on the arm if you flex the ends of the contacts.

After checking all the above, reassemble by placing all components into the case bottom (the side where the screw holes DO NOT go all the way through). Apply a TINY drop of 102 to each small spur gear axle - 6 in total. Apply a small drop of 102 to each of the stem gear axles. Using a small brush or Q-tip, place a thin smear of 102 across the circuit board contact area. A single swipe is all that is necessary. Then use the brush to place a film of 102 across the top of the 3 cluster gears' large gears. You want to fill 4 or 5 teeth with lube. Now re-insert the arm making sure that you feel some tension on the contacts as you slide it in against the circuit board. If they are not touching securely, remove the arm and bend the contacts out a bit. Do this carefully. You only want enough tension to ensure good contact. Anything more will cause excess wear and noise. Slip the case top on, reinsert the 5 screws and then test the operation. Should be good for many more years.

-Jack

Louisiana Central Railroad

The Louisiana Central Blog
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danraitz Active Member 82 posts
danraitz
I recently checked out some for the widow of a MRR friend.  As I had about 25+ to check,  I made what I'm calling the "Tortoise Tester Mk2".

Dan

100_2160.jpg100_2164.jpg

If you're not having fun, you're not doing it right! 
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Paul Mac espeelark Super User 708 posts
Paul Mac espeelark
Hey Jack - thanks for passing along the info that Circuitron provided. Always helpful!

Dan - that "Tortoise Tester Mk2" looks like the bee's knees! That will certainly give you a definitive answer if it's currently good or not. I'm of the position however that if the thermo-formed nubs on the actuation arm haven't failed, they will. That's why I open each and every one regardless and implement the process described above.

Paul Mac

Modeling the SP in Ohio                                                                                  "Bad is never good until worse happens"
https://model-railroad-hobbyist.com/node/38537
Read my Blog Index here
 
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