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Here are 2 pictures of a Dynaco ST-70 I restored for a customer. I replaced the chassis, all the caps, a few out of tolerance resistors, bias selenium, rca jacks and speaker terminals. I replaced some wires including the line cord with a 3 wire line cord. I also took the transformers apart and gave them 2 coats of primer and 2 coats of semi-gloss paint.

He gave me 2 of them to restore...

Regards,
Sal

Now the before picture...


And the after picture....

You must have cheated on the chassis. How'd you get it shiny?

Ty_Bower wrote:You must have cheated on the chassis. How'd you get it shiny?

I used chrome spray paint... only kidding. I edited my post while you responded, I bought a new reproduction stainless steel chassis from Dynakitparts.com

Sal

That is a top-notch restoration Sal. I wish there were people out here that would bring me old Dynacos to rebuild for them. I wouldn't be surrounded with so many amps just keeping my flux fume addiction up. Yellow_Light_Colorz_PDT_09

How did you clean the circuit board? Did you remove the components first?

Thanks! Here is a before and after picture of the circuit board. To answer how I cleaned the board I used a stiff toothbrush and pure alcohol and pored the alcohol on the toothbrush and brushed away, I cleaned it the best I could with a rag to get the crud off and tooth brushed it with alcohol again. Then I got Q-Tips dipped in alcohol and cleaned what I could. I then (a lot of thens... ) used a toothpick with a old tee-shirt and cleaned the nooks and crannies. I cleaned the board in 3 sections, the left, middle and the right side. The only components I removed were the capacitors before I cleaned the board.

Regards,
Sal

Sal, I can't look at your St-70 without a pair of shades on. Yellow_Light_Colorz_PDT_11 They are bright as the summer sun. Great work. It's like seeing how the orginal ST-70 would have looked when they were new in the 60's. -Min

I can see a lot of elbow grease was used also to clean the board. Were the traces on the other side in good shape? I'm surprised that the carbon comps were still in spec. Were the two 47ks in the cathodyne PI still matched?

Quote:

It's like seeing how the orginal ST-70 would have looked when they were new in the 60's.

Its far better than they looked new. Way to go Sal!!!

Sal -

Beautiful work.
It helps many Dynaco restorers to see these before and after pictures.
It provides a good baseline reference for new restorers of what is possible -- IF you take a bit more time (and spit and polish).
Some have to "see" to believe it is possible.

g. beat

Thanks for the compliment guys, I am almost done with the second ST-70 I am restoring. The first one sounds pretty damn good... Yellow_Light_Colorz_PDT_12

Regards,
Sal

Great job Sal. Your resto is an inspiration to me!

Thanks for the compliment!

Sal

Hey Sal, what will you do with that old rusty chassis? They are great for experiments etc, hope you didn't throw it out! :o

TerrySmith wrote:Hey Sal, what will you do with that old rusty chassis? They are great for experiments etc, hope you didn't throw it out! :o

There's gotta be a local engine shop that would be willing to sandblast and powdercoat for a small fee. Maybe even re-chrome if you're lucky.

Or they can bright copper plate the chassis.