Author Topic: New Resto Project- 1961 Imperial Magnavox  (Read 3174 times)

TC Chris

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #30 on: March 07, 2018, 10:13:43 PM »

As for the cabinetry if it's really yucky an application of Gojo waterless hand cleaner (the original creamy kind without pumice/grit) will get off a surprising amount of gook and is especially good at removing build up of nicotine and furniture polish.  Then a quick once over with Old English Furniture Polish (the scratch cover type) and finally a coat of two of good old Johnsons paste wax.

I certainly agree about the paste wax.  I have been working slowly but steadily on the cabinet for the 1936 GE console radio.  I don't have spray facilities so I use varnish.  The varnish I bought from Sherwin Williams was way too fast drying so I've been dosing it liberally with Penetrol so it levels better and holds a wet edge as I'm brushing.  But still, it has to be wet sanded and then brought up with hand rubbed pumice and rottenstone. After that it gets paste wax.  My real favorite was my old can of Simonize paste wax (not the automotive cleaner-wax  version) but it's almost gone, so I'll be using my Johnson's that lives under the kitchen sink.  I tend not to use paste wax on table tops that get lots of human touching because arms and hands can leave traces.  My old dark-stained gate-leg table that I use as an office conference table got Howard's but not wax.  I may try a thin coat and see if it helps.

The GE radio cabinet is a bit complex, and some parts will just get 4-0 steel wool to remove the dust bits in the varnished surface, then the wax.  Those are parts that are very skinny, not larger surfaces where the gloss shows.

Chris Campbell

electra225

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #31 on: March 25, 2018, 07:33:40 PM »
I suppose I should be more careful advising people to use steel wool on electronics chassis.  Using steel wool is how I was taught to do it.  Compressed air and certain careful procedures have allowed me to use steel wool on radio chassis and that with no problems.  My experience with Scotchbrite has not been as successful as using steel wool.  I do not use steel wool in close proximity of transformers, especially IF transformers.  But, for most other uses, I like it.  I always am careful to use compressed air and a good light to make sure I have nothing left that might cause a problem.  Scotchbrite is good for certain jobs, but it is not nearly as aggressive as steel wool.  0000 steel wool and Simichrome polish is the nectar of the gods as far as I'm concerned.  I do not use steel wool around speakers or on soft metals.  It is the berries on glass and chrome.  Scotchbrite shards left in the wrong spot can cause problems in their own right.  You need to be careful and insure you get all the debris off regardless of what you use.  I try to be careful around tube markings.  I might know what the tubes are, but the guy who comes behind me might appreciate being able to identify a tube.
I'm great at multi-tasking.  I can listen, ignore, and forget all at the same time.

Motorola Minion

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #32 on: March 27, 2018, 10:21:42 AM »
Many times there is a yellow dust covering a cadmium plated chassis. Gently dust with swiffer pad or a dry paper towel and above all, have good ventilation.

A product called "Spray-nine" will clean up a chassis from the usual aftermath of handling it for a recap.
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Dave

Motorola Minion

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #33 on: March 27, 2018, 10:24:49 AM »
A pretty sight indeed  :D The chassis looks like it was not serviced, its all original.

Check all your resistors, in my 1960 Mag most had drifted high, often more than 10%. The same resistor that is spot-on for the channel 1 circuit could be beyond 20% on channel 2. This helps tremendously when there is no front panel balance control. 
Tubes - Magical - Tubes

Dave

electra225

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #34 on: March 27, 2018, 03:34:34 PM »
I have found the 220K ohm grid resistors in Magnavox amplifiers to be drifted twice their value.  I have also found the 100 ohm (nominal) cathode bypass resistor to be burned internally.  I like to replace these resistors as a matter of course.    Using 1% resistors is also helpful to eliminate concerns with channel balance.  PB Blaster will also work to eliminate the dust found on cad plated surfaces.  Mallory made many of the electrolytic can caps Magnavox used in their equipment.  They are of good quality originally, but some of them are showing their age by now.  The coupling caps and the resistors Magnavox used were not very good quality.  Goodall caps should be replaced whenever they are encountered.  The advice to check all resistors was good.  I typically replace all the capacitors, except ceramics and 80% of all the resistors in amps.  Maybe 40% of the resistors in tuners are drifted out of spec.  I like to replace any that have drifted more than 10%.  I like to measure new resistors and choose those closest in value.  My Imperial has its balance control located in the hollow shaft of the treble control.  It takes a special screw driver to access and is a pain to deal with.
I'm great at multi-tasking.  I can listen, ignore, and forget all at the same time.

AC207

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #35 on: June 03, 2018, 11:11:55 AM »
Well, time for an update!  Over the winter I did recap the amp but the actual unit was being stored in a friend's garage... until last weekend when I was able to bring it home.  Anyway, this morning I set the amp in place, plugged some things in and was able to get power! Progress at last.  As I haven't yet done anything with the tuner I didn't push to hard to get sound- I was thrilled just seeing it light up and seeing those tubes glow for the first time in 35 years or so!

Maybe I'll pull the other components out today so we can get to work on them... or maybe I'll just clean the heck out of the cabinet!
An honest man's pillow is his peace of mind.

Bill

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #36 on: June 04, 2018, 05:50:14 AM »
That's a beautiful sight!  Keep up the good work, music is just around the corner.

Bill

AC207

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #37 on: June 04, 2018, 07:30:08 AM »
That's a beautiful sight!  Keep up the good work, music is just around the corner.

Bill

Now that I think about it, I may have gotten sound if the speaker selection switch had been in the right place... but pretty sure I turned that dial to make sure it moved freely.  Oops!  :)
An honest man's pillow is his peace of mind.

electra225

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #38 on: June 13, 2018, 12:33:51 PM »
If you can get the tubes to light without releasing any magic smoke, you are 90% there.   ;)
I'm great at multi-tasking.  I can listen, ignore, and forget all at the same time.

AC207

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #39 on: September 30, 2018, 04:59:56 PM »
Well, the summer was so darn hot I didn't make nearly the progress I had hoped for.  The autumn weather has been more favorable to working in the garage so I was able to work on my Imperial a bit today. 

The intent was to simply remove the tuner and multiplex unit but once I had removed those components I felt the need to clean and polish a little :)  I used some Dawn detergent on the turntable, Howard's Restor-A-Finish on some of the wood and some Windex on the tuner glass.  So yeah, excitement for this project greatly increased after seeing how well this is cleaning up!
An honest man's pillow is his peace of mind.

TC Chris

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Re: New Resto Project- 1961 Imperial Magnavox
« Reply #40 on: September 30, 2018, 10:39:50 PM »
My problem is that summer is so darn pleasant for other activities that I don't get much indoor work done.

Keep us updated on your progress.  It's fun to see things all cleaned up.

Chris Campbell