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Post by viperz on Feb 9, 2022 5:01:25 GMT
I started repair and restoration of 259B stepper for my 3010 Wurlitzer jukebox yesterday.
Cleaned as much as I could, cleaned all contacts, and started replacing capacitors. Interesting that capacitor across the coil of Latch relay is marked as 150uF on schematic, but parts layout in the manual shows 100uF on top of 150uF capacitor. On both of my 259B steppers, those capacitors are connected in parallel for a total value of 250uF. I will be ordering a new 250uF capacitor. The other big electrolytic is 35uF across the coil of Timing relay - closest modern equivalent is 33uF, which should work, since originals were +/-20% at best to begin with...
What I am struggling with right now is that the assemblies that are supposed to move the moving spider contacts are stuck. They are supposed to move freely in one direction, and then springs on their shafts are supposed to return them to rest. One of them barely moves when I try to push the plastic gear on the shaft (and does not return - I have to push it back), the other is completely stuck. (both are completely stuck on the other stepper). Is this something that requires complete disassembly, or should I try oiling the shafts/bearings to try to make them move freely again?
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Post by jukenorman on Feb 9, 2022 11:50:51 GMT
Hi Eugen, You probably have nothing to lose by oiling but sometimes disassambly is the only solution.
Norman.
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Post by Ron Rich on Feb 9, 2022 12:52:31 GMT
Hi Eugen, I do not know what this stepper looks like, but GUESSING, I am thinking it may be a Guardian Product ? If so, the "plastic wheels", were formed over an aluminum shaft. WRONG proceedure as the aluminum expands at a different rate then does the "plastic". This happened to all the later Seeburg, Guardian built, steppers. The only GOOD solution we found was wheel replacement with a non-formed wheel and a "loose" aluminum center. If WurliTzer did not provide replacement wheels, you will need to dis-assemble them and "shave" the shafts-- this will need repeating every few years ! Just FYI-- The "bad" ones Seeburg used were white in color, the improved ones were black. IMHO, you do not want oil on this shaft-- you may try a bit of the "silly-stuff" on a "Q stick" rubbed into the shaft area-- Oil gets into the splits in the plastic, and attracts more dirt-- Ron Rich
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Post by viperz on Feb 9, 2022 13:04:33 GMT
Hi Ron, yes, that's the one with white plastic gear wheels on aluminum shafts... Damn. Here is a quick photo of them: photos.app.goo.gl/cumL3t5SJ6YrNGUBASo I guess the whole thing needs to come apart... fun fun... Thank you for the advice.
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Post by Ron Rich on Feb 9, 2022 13:11:30 GMT
Hi Eugen, Looks awful "suspicious" -- It definitely is of a slightly different design -- but it sure looks to be of Guardian manufacture ? Ron Rich
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Post by viperz on Feb 9, 2022 13:37:19 GMT
Hi Ron, not sure about the manufacturer, but it does exactly what you described. Those plastic gears are supposed to be 'stepped' using small solenoids, which would move two sets of spider contacts in a circle making proper connections. When the stepping is done, solenoid that prevents wheels from spinning back would disengage little "tooth brake", and springs on the shaft are supposed to return both sets of contacts back to rest. So these plastic gears are supposed to be freely rotating on the metal shafts. I guess the crap white plastic contracted/shrank over time around the aluminum... I have never done this, but I guess I have no choice but to disassemble the whole mechanics now.
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Post by Ron Rich on Feb 9, 2022 23:13:48 GMT
Hi Eugen, It is a Guardian built to WurliTzer specs-- No the plastic does not "shrink", it splits-- and yep-- I know what you going to be "doing", for awhile ! Advise: PHOTO's--more PHOTO's and MUCHO More photo's ! Ron Rich
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Post by viperz on Feb 11, 2022 17:38:21 GMT
Finished replacing all capacitors today, then started to disassemble the mechanical portion to pull out the stepper assembly. Took a ton of photos, marked all the screw positions. Still trying to figure out how to pull out only the stepper portion. So far I unscrewed the two contact boards on the sides (now I can clean all contacts properly). I see three nuts that hold the whole assembly on rubber insulators. The problem is the three coil assemblies - wires to the top contacts go through the top of the frame, wires to the coils themselves go through the bottom. Ideally I want to pull out the stepping assemblies with just wiper contacts on them, remove wiper contacts, and have just the shafts with plastic gears on them. We will see...
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Post by viperz on Feb 12, 2022 19:50:44 GMT
OK, so the gear assemblies are out of the main frame. photos.app.goo.gl/e9dmGjv458M6iaTc8 and photos.app.goo.gl/AUxuTqyydwMveYPG6I can see a couple of small cracks in the gears where they are pressed onto the shafts, but they should not affect the motion of the assembly. The assembly has metal shafts rotating inside metal frames - on one side of the shaft we have plastic gear (and return spring), on the other side we have the spider contacts. The spider contacts' collar has two set screws connecting them to the shaft, and it does not look like those set screws are meant to be removed - they are drilled round inside and filled with thread locker. I am afraid of using penetrating oil or 3-in-1 in case it may touch the plastic gear, so I am using thin sewing machine oil - putting it onto the shaft and waiting for it to sip in (I also cleaned and oiled the return springs). The assembly with 4 contacts, which only has about 90 degrees of motion, almost comes back after about an hour. The assembly with 2 contacts, which have about ~300 degrees of motion, moves ok by hand, but does not come back on its own.
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Post by Ron Rich on Feb 12, 2022 20:02:04 GMT
Hi Eugen, I would not use "sewing machine oil" on this, as I have no idea as to what that is-- You will need to remove all "contaminants", and polish the shafts, real well, if they are like the ones used on Seeburgs-- A small drop of 20 wt. also works for awhile-- till the plastic expands again --- I could never attribute the expansion of the shafts to the 20 wt. oil -- Ron Rich
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Post by viperz on Feb 12, 2022 21:16:44 GMT
Ron, the problem is that to access the shafts I need to remove the set screws that holds spider contact collars. Those set screws are round inside, so none of my metric or imperial hex drivers can move them. Sewing machine oil is a very light weight oil, at least it penetrates onto the shaft for now. I don't see how metal shaft would expand inside the metal frame either?
So if anyone ever removed those set screws (looks like they are the same in Seeburg, Wurlitzer, whatever Guardians have built), please help me with what tool to use. Thanks.
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Post by viperz on Feb 13, 2022 2:19:17 GMT
Apparently I don't have the right tools... Need Bristol wrench... Just ordered a set out of USA, will have to wait until it arrives - www.ebay.ca/itm/181062812929
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Post by Ron Rich on Feb 13, 2022 3:25:56 GMT
Hi Eugen, Seeburg's do not have the contacts connected directly to the plastic, as do the WurliTzers. IF, this is the same problem as Seeburg's had, the aluminum shaft the plastic is molded to, expands, causing the plastic to split, and "get fat", so it can not turn freely inside the stepper bearing housing. Sounds as if that's the problem here ? Do you know the "chemical make-up" of that sewing machine oil-- Neither do I, and I can't say if it re-acts to the plastic in the wheels ? I KNOW that WD 40 is NOT to be used in this circumstance as it does tend to soften some plastics---Did you also purchase a bottle of "red glyph(tol)" to re seal the grub Bristol screws, which are painted with glyph to prevent an contamination to the screw threads. ? Ron Rich
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Post by viperz on Mar 7, 2022 23:52:11 GMT
OK, so only four weeks later, I received my Bristol spline wrenches. Took apart my one spare stepping assembly with no issues. Of course, took me forever to take apart the two of mine. One metal sleeve was previously drilled out, retapped, so took me a bit to figure out that they actually used the regular small imperial hex screw. All three plastic shafts have a few cracks in them. So I guess I will clean them up with alcohol, superglue the cracks, then sand them down a little using something like 400 or 600 grit sandpaper? The metal shaft would fit into the drill chuck perfectly. Ron, don't have any red stuff, but I have a bottle of regular blue threadlocker. Here is one of them: photos.app.goo.gl/n4SdXVzm2JBTagc19And here are all three: photos.app.goo.gl/9G9bvCKu9XcUfnTp9
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Post by Ron Rich on Mar 8, 2022 14:18:22 GMT
Hi Eugen, Quitchorbitchin'-- You got the wrenches right ? After all, they had to fly all the way from Bristol, to you ! All kidding aside-- Yep-- them thar wheels look egg-zactly the same as the Seeburg style--including the splits--I don't know if up-grade wheels were ever made, or offered ? Good luck-- let us know how it comes out--Ron Rich
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