Dual 1229 Motor Question

[Tim D]

I've been slowly restoring a 1229 that I picked up from the big auction site and the most recent item is that I'm wondering if I might have a motor issue. Here's what I'm seeing.

I disassembled the motor to clean and oil the bearings and I noticed that on the bottom of the motor shaft were it sits on the the thrust plate in the lower bearing it is showing a small area of brass color where it would contact the thrust plate. Is this brass color normal or has it burned though the stainless plating and I'm on borrowed time? I'm hoping that one of the guys that works on Duals would know.

I did use the iphone app to measure W&F and it showed 0.25%. I know these apps aren't the best but I am hearing that this is a bit high for the 1229 and it made me pay more attention to these kinds of details. It is able to get up to speed and all speeds work. I'm just worried about longevity and also the W&F might be affected if the shaft is damaged.

 

[tourmax]

Higher WOW numbers on idler tables are usually in the idler system somewhere.

The rubber condition, the platter surface cleanliness (just needs a good wipe down on the running surface with some IPA and then don’t contaminate it with you finger oils) or the idler spindle and linkage cleaning/lubrication are the usual culprits.

The center bearing can also be a source of higher wow numbers if it hasn’t been cleaned and relubricated recently

My 1229Q returns a wow number of 0.05 on the iphone app:



And thats a repeatable number on successive runs. Well, it will vary between 0.05 and 0.06 on the app, but thats still pretty consistent.

But mine has also had a lot of work done:



It uses an aftermarket idler and a dry moly graphite impregnated “multi-ball” center bearing (aftermarket). The rest of the table gets torn down once a year and cleaned, adjusted and relubricated. I use synthetic oils and Gadus grease (modern equivalent for the original Alvania grease) specifically for the various components in the table:



Its a regular enough maintenance thing for me I built a TT rotisserie maint stand:





Tearing it down once a year is a bit of overkill for most people and I’ll admit I’m a little “over the top” on upkeep for both my 1229Q and 1249 (my 1249 is regularly in the 0.03/0.04 range) tables, but I’m retired and have lots of time to spend on fettling them.



On a less worked over 1229, I would say anything around/under 0.10 is acceptable or a few ticks over that is probably still good. Highly doubtful you’ll hear any difference when playing records at anything under that.

They were only rated at 0.06 wow from the oem brand new: https://www.dual-reference.com/tables/1229.htm

0.25 needs some work though. They’re capable of better number than that even in a somewhat less than ideal condition.

I’d chase down the idler wheel area first if it were mine…

 

[Tim D]

The aftermarket tire is interesting. What is the source?

I'm not seeing anything wrong with the current tire, but I've replaced lotsa tires on other TT's. My usual source is the VoM site.

I'm still hoping to hear from the Dual guys about that brass colored spot on the bottom of the shaft. Is that normal or a worry?

 

[tourmax]

The aftermarket tire is interesting. What is the source?

I'm not seeing anything wrong with the current tire, but I've replaced lotsa tires on other TT's. My usual source is the VoM site.

I'm still hoping to hear from the Dual guys about that brass colored spot on the bottom of the shaft. Is that normal or a worry?

Sorry, forum rules won’t let me post the source. Not allowed to potentially advertise for a non registered seller.

Google custom 1229 idler and it should turn up. I believe they also sell them on the auction site. But be forewarned: they’re not cheap.

Same place sells the center bearing and those oil bottles I use on their web site.

The idler can look perfectly fine and even feel somewhat supple, but still be causing wow and flutter. 45+ year old rubber just doesn’t behave like a new/newer idler does. The brass center bushing in the idler can also wear over 45+ years of use and can allow it to “rumble” on its shaft a bit too much. Especially of it hasn’t been oiled on a somewhat regular basis over those 45+ years. The new idler I’m using also does away with the possibility of wear on the brass center bushing and makes it a nice close tolerance fit… like when it was new.

I’d have to see the motor shaft and bushings to be able to tell you either way if its good or not…

 

[analogadict]

The Dual idler drive tables have pitch control and to enable that ,each step on the pulley has a taper. If the idler bush is worn out in the slightest, or the retaining clip on the top is loose ,then the idler rides up and down on the pulley . This leads to higher wow . Check the idler for these two issues.

Regards,

 

[Tim D]

Thanks analogadict,

What's an "idler bush"? Did you mean bushing?

I'll check the nylon clip and bushing. Good idea!

I'm still hoping to hear from the Dual guys about that brass colored spot on the bottom of the shaft. Is that normal or a worry?

 

[tourmax]

Thanks analogadict,

What's an "idler bush"? Did you mean bushing?

I'll check the nylon clip and bushing. Good idea!

I'm still hoping to hear from the Dual guys about that brass colored spot on the bottom of the shaft. Is that normal or a worry?

Idler wheel center bushing.

 

[Tim D]

He are some pictures. Can anyone confirm that the bottom of the motor shaft is normal or damaged from these?

 

[Osibisa]

Wow, I've serviced a few 1219 & 1229 motors and none looked like the one you have, was there any lubrication left in the bottom bearing when you disassembled? The copper disc was designed to wear before the motor shaft, are there any remains of the disc? Motor shaft should not have the amount of wear shown in your images.

 

[Tim D]

Wow, I've serviced a few 1219 & 1229 motors and none looked like the one you have, was there any lubrication left in the bottom bearing when you disassembled? The copper disc was designed to wear before the motor shaft, are there any remains of the disc? Motor shaft should not have the amount of wear shown in your images.

Thanks! That's the kind or response that I've been needing. Seems I probably have a damaged shaft then.

It's hard to see the disk through the bearing. The hole is only about 1/4" wide. I think I can see wear on it though. What I will do is to drill out the rivets and get a closer look at the disk. I'll probably do it this weekend when I can get my drill press out.

 

[RWood]

Drilling out the bottom bearing seems to be the best way to clean and then relube it anyway. #4 machine screw sets go back in.

User on VE named mrow sells kits for this job, along with the other handy parts.

Let us know what you see about the disc.

 

[Tim D]

Drilling out the bottom bearing seems to be the best way to clean and then relube it anyway. #4 machine screw sets go back in.

User on VE named mrow sells kits for this job, along with the other handy parts.

Let us know what you see about the disc.

Thanks RWood,

I've got Don's PDF, grease and steuerpimples for servicing Duals. Great guy. I'll go over to VE and look around for info on his kit.

I've posted a WTB in BT for a replacement motor (or just the rotor) to see if I can skip past trying to work with the damaged shaft.

 

[Tim D]

So, I got ambitious and pulled out the drill press and drilled out the rivets holding the thrust bearing in place. Not much interesting to report. The little copper disk has stains on both sides, but there isn't any concerning wear on it. Also the felt ring is in great condition. I now just need to clean it up a bit and find the tiny bolts to put it back together. Any idea on what are the size of bolts needed?

 

[RWood]

#4 machine screw 3/8” length with a washer, lock washer and nut. 12 items total.

Was the motor noisy before?

 

[Tim D]

Thanks RWood.

Exactly what I needed!

 

[mfenberg]

The aftermarket tire is interesting. What is the source?

I'm not seeing anything wrong with the current tire, but I've replaced lotsa tires on other TT's. My usual source is the VoM site.

I'm still hoping to hear from the Dual guys about that brass colored spot on the bottom of the shaft. Is that normal or a worry?

I've got the same idler wheel on my 1219! Here's the link, check out post #8... HERE

 

[Tim D]

So, I obtained another motor courtesy of a kind AK member and that has fixed my problem. After doing the full service, the new motor is smoother and the W&F is hugely better at 0.05. It runs quiet and is probably the way that Dual intended it to be. Thanks everyone for your support. On to final cleanup and restoration of the plinth now.

 

[TechEd58]

<snip>

It uses an aftermarket idler and a dry moly graphite impregnated “multi-ball” center bearing (aftermarket). The rest of the table gets torn down once a year and cleaned, adjusted and relubricated. I use synthetic oils and Gadus grease (modern equivalent for the original Alvania grease) specifically for the various components in the table:

I have used the new aftermarket AV idler on my 1216 restoration and I can verify its quality.

I had had a retread idler, but it wasn't stiff enough and performance was poor.

I didn't touch the platter bearing, because I'm a Garrard guy and the Dual bearings seem to me to be harder to assess because Dual specifies chainsaw/stiction oil, whereas the Garrards use regular, clean oil.