Cincinatti 15x54 traytop inconsistent start

[JENIUS]

Not a machinist, 1st time lathe owner. I bought a 15x54 cincinatti tray-top, non-hydrashift, lathe. According to the manual, it is an "all electric drive verses the clutch drive model" I witnessed it run off of the rotary phase converter at the previous owners shop. He mentioned "in-consistent" starting when engaging the head stock spindle start/stop lever, but it functioned at his shop. I am now experiencing the inconsistent starting issue. The electrical appears correct, but i (and a machinist friend of mine) have only been able to get the spindle to turn on 2 occasions. The spindle will turn about 1/16 turn in forward and reverse every time, but has only turned on fully twice. I assume there is switch or adjustment to be made. I looked at "clutch adjustments" but my model is the all "electric model" according to the manual. There is also a filter located in the headstock gear area that is also actuated by the start rod, although this is not a hydra shift model. The spindle rotates in neutral by hand and you can feel the gears engage when changing speeds on the transmission while it is off. Where do i start? Edit: Added some pics of the drum switch and oil filter.

 

[Elwood1968]

Do you have a copy of the parts and service manual T-107-3?

Pub T-107-3 on vintagemachinery.org

It shows the wiring diagrams for the electrically controlled (i.e. non-clutch controlled) lathes. Perhaps a problem with the drum switch?

 

[JENIUS]

Do you have a copy of the parts and service manual T-107-3?

Pub T-107-3 on vintagemachinery.org

It shows the wiring diagrams for the electrically controlled (i.e. non-clutch controlled) lathes. Perhaps a problem with the drum switch?

I do have that puplication and have reviewed it, The drum switch on my lathe is at the top of the gear box as opposed to under it as shown in the diagram on page 71. I examined the drum switch and contacts, they "appear" intact and corrosion free, and rotate positions when the engagement handle is moved from forward to reverse and neutral.

 

[Elwood1968]

I'd want to verify the continuity of each drum circuit per the diagram (with power disconnected!). Also, have you checked the heaters for correct spec based on your input voltage? Could be you have the wrong size(s) or one or both defective.

 

[JENIUS]

The continuity checks are next on my list. Although i am adept at 12v and to a lesser extent residential 110/220v, the mention of "heaters" as it applies to this lathe and its controls is beyond my current level of understanding. I am sure i could check them, but have no experience identifying them nor do i understand their function.

 

[Elwood1968]

While I generally agree with Thermite's advice here, especially the part about bad connections and faulty crimps, my experience with heaters is a bit different. When I purchased my Toolmaster mill, it was set up for 440v with the appropriate heaters on the main spindle motor and the X-axis power feed motor. I'm running 220v three phase, and when I first test ran the mill in my shop, I did not have the correct heaters for 200v, so ran it with the heaters as it arrived. The spindle motor stopped within about two minutes. Once the heaters had cooled enough, it re-started normally, then died again. Granted, the very short spindle run time before failure on your TrayTop lathe suggests that the heater ratings are likely not the problem.

 

[JENIUS]

It certainly acts like an out of adjustment mechanical to electrical connection point. But i can find no indication of that so far.

 

[JENIUS]

Interesting, I did see in anothe thread about a filter on a hydra shift cincinatti. Mine is not a hydra shift, but there is a filter that has a lever arm that is actuated by the drum switch activation linkage. That may be the case. Although i cannot find it mentioned in the manual thus far. I better pull it out and clean it.

 

[JENIUS]

Added a couple pics to the original post for clarity.

 

[JohnEvans]

How are you powering it? If rotary converter you will need 2X the lathe motor HP for the idler not having a clutch.

 

[JENIUS]

It is powered by a 7.5 HORSE RPC. I got a little more info out of the guy i bought it from concerning the hard start. He said he had to be quick and forcefull with the spindle engage handles and some times had to cycle between neutral and fwd. or rev. Out of frustration i tried his rough start procedure, and to my surprise it worked. However, i now know why there is slop in the handles, this condition must have been a larger issue judging from the slop in the handles from beating them in and out of gear. So despite my checking the accessible contacts in the drum switch and finding continuity there, i am guessing there are other issues with it. The matching drum switches i found online have been discontinued for some time and are very expensive. Even at that, i am still not entirely sure 100% that it is the drum switch. I would hate to buy a drum switch and have it still not work. At this stage a VFD may make more sense, although the original electrical panel wiring is a work of art, and it would be a shame to remove it. Any other ideas as to why it requires this violent of starting procedure?

 

[JENIUS]

Not desperate, but a tool to me is one that works every time i need it, even though i may only use the lathe once in a while. I certainly have no pressing need for the lathe, but i dont want to spend more weekends without results, as the lathe will be handy for support of my other pursuits, motorcycles, hot rods, etc. If i can find a clear path to full functionality, i will do that over continuous troubleshooting.