Russco Cue Master build

[Blackdog61]

I am now the owner of two Cue Masters that each seem to be in very good condition which hopefully means that it won’t take too much time, effort and expense to get them running well. Hopefully………..
Only one had a power switch so I chose to start with that one. A quick spin of the motor was encouraging so I wired a power cord and turned it on. The motor seems to be fairly quiet, which I judged by suspending the turntable with both hands and detect the slightest vibration and a barely audible mechanical hum. A heavy plinth should take care of that. All three motor mounts are intact and flexible so they are probably OK. The platter spindle and steel ball look great with no flat spot on the ball. The well appears to have the steel ball and from what I can see it looks OK. Unfortunately, the nut and grub screw seem to be seized tight and I’m inclined to leave that alone for now. I cleaned the well and gave it some hydraulic oil (because it was at hand) before inserting the platter. It spins very quietly.
Both idler wheels appear to be free of defects or flat spots, and flexible. The idler arms are shot; in pieces and a wobbly mess.
Do I try to use the best of the idler wheels and just replace the arm or should I go ahead and get a new wheel?
I am very encouraged by the condition of these. They came to the seller with Shure M232 tonearms and I negotiated a lower price and he kept the arms. I’ll put a Syntec arm on this to start with. Any guidance from here will help.

 

[Blackdog61]

 

[Blackdog61]

Alright. After letting the motor run for about two hours it started to bog down a bit and pulse, for lack of a better word. I removed the bottom cover and cleaned it, although it didn’t look too bad. I replaced the ball bearing and oiled it. It seems quieter and I’ll let it run to see if it really is OK. I’m ordering a new idler arm from Serge and will use the better of the two wheels for now.

 

[Blackdog61]

Serge emailed to tell me the idler arm is out of stock for at least another month so I am going to either try to repair what I have or make a new one. I have what is shown in the pic above and another one with a good wheel mounted to the arm but it is missing the long post which goes to the lever part. I can possibly drill that one out and secure a post in that. If I made one I have some ebony and pakkawood which is a composite of ebony and phenolic resin. The later is very dense and hard but would be stiff. Not sure where to go with this.

 

[Blackdog61]

I had some free time today so I went ahead and took a crack at an idler arm. With parts from two arms to work with, I reused the idler axle and the longer one which goes into the lever. They each had grooves on the end I pressed into the crosspiece made from pakkawood, secured with CA glue. There is very little play in the idler and it will spin freely so it seems to be good. Success! Although I am basically clueless regarding the best front to back motor position I kind of understand the adjustment screws on the front. Still, the rumble at 33 seems to be minimal, but 45 and 78 are pretty bad. This is regardless of the respective screw adjustments. I may need to address the motor again because after it warms up it pulses a bit and it can be felt at the plinth. I did center the capstan but it may need to be done again.
Any guidance regarding setting this up for proper operation will be helpful.

 

[Blackdog61]

My phone app says it is running 25rpm at 33 and 35rpm at 45. Is that the motor?? After letting it cool off it was 33.7rpm for a few minutes and dropped to 28rpm. Looks like the motor will get completely gone through.

 

[adnick]

My phone app says it is running 25rpm at 33 and 35rpm at 45. Is that the motor?? After letting it cool off it was 33.7rpm for a few minutes and dropped to 28rpm. Looks like the motor will get completely gone through.

Possibly some “resistance” causing the reduction, the screws are idler pressure adjustments, ROK calls them “fine speed adjustments” and platter height can have minor effects on speed/vibration

Check the voltage to the motor before and after the switch/capacitor, you could even switch out parts between tables to troubleshoot…

The Derlin idler makes a noticeable difference on my Studio Pro….



Good luck,
Andy

 

[Blackdog61]

Thanks Andy. The other one had #67 written boldly in Sharpie and I can only assume it was the lot number being bid on. Since I couldn’t remove it I decided to paint it. A can of etching primer and bronze hammer tone paint has it is looking stellar. I disassembled that motor and cleaned it thoroughly, although it looked good other than some sludge in the bottom bearing. Back together I ran it for about thirty minutes and barely got warm. My hope is to get this one running this evening. once it’s playing music I will better evaluate and consider improvements going forward.
I removed the grub screw and can find no gunk or wear so I don’t know that this one got much use. Weird. Has anyone discussed just using threaded delrin rod there? Is there some magic in having delrin in a metal bolt? Curious.

 

[Blackdog61]

Wow! We have music and it’s big! I put an old Empire with a worn conical at the business end and set the VTF to about 1.6g. Even with a very rough alignment and sitting on a rolling file crate it sounds huge. Rumble is inaudible. Can’t wait to hear this in a stacked plywood plinth. Thanks for the inspiration everyone.

 

[Blackdog61]

Really stoked about this. One minor thing I should address is there is a hum with the stylus in the groove. 1-2mm above the groove it doesn’t hum. Is there a connection I missed? I mounted a Shure M55 with VividLine cart and it is ultra smooth.

 

[adnick]

Congrats, for some idlers have a special appeal, but it’s a deep hole

When you build the plinth I’d recommend making it large enough for another tonearm off of the metal table…

VR
Andy

 

[Blackdog61]

Congrats, for some idlers have a special appeal, but it’s a deep hole

When you build the plinth I’d recommend making it large enough for another tonearm off of the metal table…

VR
Andy

That’s the plan. I have plenty of birch plywood for a stacked plinth about 17”D x 21”W. Minor setback about two hrs in when the motor started sounding like pennies in a can and the speed……..wasn’t. It didn’t feel painfully hot but after a few minutes it cooled off and behaved. Probably need to tear it down again. Any advice there?

 

[adnick]

That’s the plan. I have plenty of birch plywood for a stacked plinth about 17”D x 21”W. Minor setback about two hrs in when the motor started sounding like pennies in a can and the speed……..wasn’t. It didn’t feel painfully hot but after a few minutes it cooled off and behaved. Probably need to tear it down again. Any advice there?

Send @BillWojo a note, he has more experience with that older motor, @MisterDK (Duane) may have worked on those motors also….I’d check the voltage from the run capacitor when it acts up, just to be sure there’s no other causes.

 

[adnick]

You can also make a thin layered Armboard, after the Studio Pro pattern, to mount over the stock arm location…..that will help.

 

[Blackdog61]

You can also make a thin layered Armboard, after the Studio Pro pattern, to mount over the stock arm location…..that will help.

I can feel motor vibration in the tonearm so I considered that. The Cue Master has three bolts to secure the tonearm so I thought about using those and maybe the one for the armrest. If you have a pattern for that I will appreciate it. Otherwise, I may do something that only comes as far forward as the armrest. !/2” birch ply OK for that? Should it be tight to the aluminum plinth or be isolated, maybe 1/4” Sorbothane or something. I am happy with this Syntec arm. An arm board would make it easier to incorporate a lifter.

 

[Blackdog61]

After running for about ten minutes the motor was only 90 degrees F at the center (I couldn’t get the red dot of the thermometer closer to the top). After flipping the album over but not starting it, I walked away to feed the dogs and get fresh coffee. Coming back for side two, the motor was knocking and it measured 111 degrees F. Looks like another trip inside the motor. I’m a bit stumped because it looked very clean when I assembled it. Possibly the bronze sleeves are dry. The red oil caps don’t actually go through to the motor shaft but serve as a reservoir for replenishment through the outside of those sleeves. that what it looks like. After another cleaning my plan is to fully coat those with oil and see if it is absorbed. I only put a few drops in the lower ball bearing area and a light film on the shaft.

 

[adnick]

After running for about ten minutes the motor was only 90 degrees F at the center (I couldn’t get the red dot of the thermometer closer to the top). After flipping the album over but not starting it, I walked away to feed the dogs and get fresh coffee. Coming back for side two, the motor was knocking and it measured 111 degrees F. Looks like another trip inside the motor. I’m a bit stumped because it looked very clean when I assembled it. Possibly the bronze sleeves are dry. The red oil caps don’t actually go through to the motor shaft but serve as a reservoir for replenishment through the outside of those sleeves. that what it looks like. After another cleaning my plan is to fully coat those with oil and see if it is absorbed. I only put a few drops in the lower ball bearing area and a light film on the shaft.

That would not be considered “hot” for that type motor, did you check the voltage? Doesn’t mean there’s not drag within, in my testing those type motors make more noise above 115 - 120v and start having speed issues below 100v @60hz *

The higher line voltage of today doesn’t have an effect on speed, just noise, and lowered line voltage to a certain point won’t effectively reduce speed until the motor starts to have problems functioning but a bad capacitor will present issues…

*Ability to adjust both voltage & Hz change my observations listed above….

Reference the armboard: I’d use the tonearm mount location and the tonearm rest as the hold down, the pattern is up to you unless you want it to look more like a Studio Pro armboard?

 

[Blackdog61]

I didn’t check the voltage but I did check the capon the other table and it measures 3.7 so that’s probably good. Bill didn‘t suspect a bad cap. Since the other table is just sitting I may disassemble it, paint it and thoroughly go through the motor in hopes of making that the new number one. I’ll Make an arm board on that since it lacks an arm.

 

[adnick]

Bill is a better source on motors

 

[Blackdog61]

Unable to find a 3.75mfd cap I bought a 3.5mfd polypropylene cap sold to run ceiling fans. Bill thought it should work fine so we will see. I serviced the other motor and am confident it is right as rain and it ran very well until the speed dropped to 26rpm. Has to be the cap. Also made an armboard from 1/2” birch. Will update when it’s consistently making music.