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CT-F1250 Reel Motor Rebuild (CT-F800/900/950/1250)

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Just before leaving for vacation this summer my CT-F1250 decided to take a vacation also and just stopped dead in it's tracks. No motor drive at all? I was a little fustrated not having the time to dig into and correct the problem. Don't like having things staring me in the face that do not operate properly. So after a few days back and jet lag recovery I decide to crack open the beast and try to determine the problem. I first checked for voltage to the motor before just tearing in to it. Voltage was present when engaging the play button. So I cut the wires very close to the posts and proceed to open er' up. I expected the motor to be pretty dirty, but suprisingly it was alot cleaner than I anticipated. After doing the complete workout of the proceeding steps I only encountered one small problem. While cleaning the brushes one brush detatched itself from the armiture. I had to solder that mustard seed size brush back on without having any magnified goggles/glasses. But I got er' done. Checked motor every step of the way before complete installation by temporarily attaching the wires and pressing play. Once after motor was assembled, again when the motor was placed into the outer case, again after installed into the deck. I don't like doing things twice or thirds!! Altogether about an hour and a half to get the deck back into working order. I urge you to get this done by DIY or by a pro. My deck proved the motor does not have to be badly soiled to stop cold on a dead spot! :thmbsp:
 
madpioneer said:
Just before leaving for vacation this summer my CT-F1250 decided to take a vacation also and just stopped dead in it's tracks. No motor drive at all? I was a little fustrated not having the time to dig into and correct the problem. Don't like having things staring me in the face that do not operate properly. So after a few days back and jet lag recovery I decide to crack open the beast and try to determine the problem. I first checked for voltage to the motor before just tearing in to it. Voltage was present when engaging the play button. So I cut the wires very close to the posts and proceed to open er' up. I expected the motor to be pretty dirty, but suprisingly it was alot cleaner than I anticipated. After doing the complete workout of the proceeding steps I only encountered one small problem. While cleaning the brushes one brush detatched itself from the armiture. I had to solder that mustard seed size brush back on without having any magnified goggles/glasses. But I got er' done. Checked motor every step of the way before complete installation by temporarily attaching the wires and pressing play. Once after motor was assembled, again when the motor was placed into the outer case, again after installed into the deck. I don't like doing things twice or thirds!! Altogether about an hour and a half to get the deck back into working order. I urge you to get this done by DIY or by a pro. My deck proved the motor does not have to be badly soiled to stop cold on a dead spot! :thmbsp:
Click to expand...
If a brush detaches, do not try soldering it back on. Re-attach it with what it was originally attached with: a silver-bearing, highly conductive epoxy. For such occasions I use Chemtronics CW2400 Conductive Epoxy. It is expensive stuff (over $20 for a .5 oz pkg), but it will go a long way. I have used it to re-attach these brushes, fix conductive traces in slide pots, repaired PCB traces (bridging fractures), etc.

Enjoy,
Rich P
 
For those that might want to try substituting some other motor for the one in consideration in this thread...

Just because a motor screws in and rotates in the correct direction, does not make it a suitable substitute for the original. There are many parameters that must be considered: speed, torque, current, voltage, thermal characteristics, current and voltage operating range, etc. Finding a deck with a substitute motor does not qualify the motor for use in this deck. The transport and motor drive circuitry is designed, specifically for the original motor. I do not recommend substitution of these motors without consideration of the required design criteria, which are not available outside the Pioneer design group, and not even to them any longer.

Disregard at your own risk.

Rich P
 
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Pustelniakr,

Did you ever find a source for the brushes? My Sanyo M9935K boombox motor has brushes like those shown and, wow, there is about no more than 1 mm worth of material on the brushes. My motor runs slightly slow but would like to either rebuild mine or find an equivalent motor to use. One note, though, is that it looks like the armature on mine is very badly worn. Instead of straight all the way across my dips about 1/8" in the middle.

Any recommendations?
 
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The motors that are the focus of this thread do not significantly wear the brushes. Unless you break one loose and lose it, you should not need to replace them.

Sorry. I have not found a source for brushes. That is the way it is with so much of this hobby. Parts units are your friend.

Enjoy,
Rich P
 
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Well done, especially the pictures- I think of the cutting open of tape deck motors I've done over the years with similar repairs and no-one (especially the hapless customer) ever really knows what's involved- thank goodness for digital cameras. These pictorials are going to be really useful down the track for future restorers. Kudos.
On another note, have you ever come across a centrifugal governed motor that actually has a decent performance on the W&F meter after a rebuild? I haven't, but I often wonder whether they were much good to start with- the pre servo controlled motors were pretty crap standalone as compared to a servo motor- that's why they needed the massive flywheels to get partially decent specs and then the associated high current startup was needed to get a reasonable spin up time. If you could replace them with a modern (1980s vintage!) electronic servo motor and be happy with a slower startup from stop or drop-in from pause- you have a better performing deck.
 
The centrifugally regulated motors discussed here were used to supply light torque to the take-up reel only. The capstan motor is most influencial in wow and flutter performance. Generally, the capstan motor is some sort of closed loop servo motor with these TOTL Pioneer decks. Also, one MUST obtain capstan belts that are originally specified width, diameter, and THICKNESS. The thickness is what is hard to obtain. After market belts tend to be at least 50% too thick, sending wow and flutter through the roof.

Enjoy,
Rich P
 
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Thankyou!

That was an unbelievable post and you deserve a lot of credit for what must have been quite an effort! Bravo to you, Sir!
 
pustelniakr said:
The centrifugally regulated motors discussed here were used to supply light torque to the take-up reel only. The capstan motor is most influencial in wow and flutter performance. Generally, the capstan motor is some sort of closed loop servo motor with these TOTL Pioneer decks. Also, one MUST obtain capstan belts that are originally specified width, diameter, and THICKNESS. The thickness is what is hard to obtain. After market belts tend to be at least 50% too thick, sending wow and flutter through the roof.

Enjoy,
Rich P
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Rich,
Who has the correct (thickness) replacement belts for Pioneer?
Thanks
Bill
 
Admiral said:
Rich,
Who has the correct (thickness) replacement belts for Pioneer?
Thanks
Bill
Click to expand...
Unfortunately, the OEM capstan belt is no longer available for the CT-F1250, but it remains available for the CT-F900 and CT-F950. Here is the source:

https://parts.pioneerelectronics.com/

I have had pretty good luck with this source for Pioneer belts. The capstan belts are not OEM, but, at least they will work decently: https://www.vintage-electronics.net/apioneerbeltkit.aspx

Remember, the capstan belt is what I am talking about for necessary thickness, not the other belts that may be present.

Enjoy,
Rich P
 
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I've got a CT-F850 with a dodgy reel motor - just today it started to cut out a lot and on fast forward and rewind you could see it running through a few dead spots. Is the motor the same in the 850 as the other Pioneer models you've mentioned? If I were to rebuild, following your instructions would be the way to go.
 
QSilver said:
I've got a CT-F850 with a dodgy reel motor - just today it started to cut out a lot and on fast forward and rewind you could see it running through a few dead spots. Is the motor the same in the 850 as the other Pioneer models you've mentioned? If I were to rebuild, following your instructions would be the way to go.
Click to expand...
Yes, same motor and rebuild. http://parts.pioneerelectronics.com/part.asp?productNum=RXM-047 Sounds like the armature and brushed need to be cleaned. Follow Rich's instructions and be very careful with the brushes.
 
Rich-
I just wanted to thank you for this write-up. I re-built my CTF-950 take-up motor Sunday (during the hurricane). The deck works great now!
I actually removed just the motor to rebuild, and not the entire transport mechanism. The belts and idler tire looked and worked good, it's also not my main cassette deck.

Thanks again!
 
I always had luck with PRB belts. But it has been 15 Years since I worked on cassettes so their parts standards might have changed since then (Doubtful, since they pride themselves to be the belt source for A/V equipment. But companies do get bought off and fundamentals sometimes suffer).
 
wonderful write-up.....i don't see the ct-f750 listed but i have 2 with the same issue..1 worse than the other. i've never been scared to try something new so if this will help solve my issue i'll dive right in....also, i do not have a contact burnishing tool...anything else i could use?
 
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d.russell said:
wonderful write-up.....i don't see the ct-f750 listed but i have 2 with the same issue..1 worse than the other. i've never been scared to try something new so if this will help solve my issue i'll dive right in....also, i do not have a contact burnishing tool...anything else i could use?
Click to expand...
A strip of 1500 grit silicone carbide sandpaper, drawn between the contacts, once per contact side. The plating on the contacts (if present) is very thin. Do not remove it or corrosion will be an issue. Examine the contacts, for results, using a jeweler's loupe. Stop when contact surface is clean. Apply a bit of extra contact pressure while cleaning (carefully).

Enjoy,
Rich P
 
my 1979 ct-f1250

bought it new in 79...died in the 90"s. glad I kept it. your post showing how to rebuild the take-up motor was a life saver. followed your instructions to the letter(didn't want a paper weight) and she's back running again!!! thanks so much. when attaching to my dremel I lightly wrapped a bread twisty around the weights to keep them from low earth orbit.

Mike
SA Texas
 
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