[morzh]

I have just taken the board to the restoration place. Huge antique warehouse, they restore what they can.

So, the question is, should I have gloss or semi-gloss finish?
Who thinks what?

[Chas]

A-K used shellac in many forms for wood and metal finishes. Tinted shellac for wood finishing and pigmented shellac for metal. Mixed with naphtha for crackle finish. Often, aggressive cleaning with alcohol will remove both the wood and metal finishes. Wood grain metal panel of the A-K 55 Kiel table will be ruined as well as the painted device cans on the chassis if splattered with alcohol...

The filler in the mahogany on the breadboard is intact. removal of the tinted shellac can be done with alcohol/rags and wood chips. If the color of the board is brighter and desirable then white shellac applied and then French Polished will bring back the OEM "Piano" finish. Many online sites have the French Polish method well described..

Allan Douglas preferred that type of finish over changing to varnish. Lacquer is also an option in a transparent toner. With toner it can be highlighted or darken around instruments and lighter in open areas. A coat of gloss clear lacquer would complete the job. Done in a hour or so, left for a week to cure hard...

Colored tinted shellac may be hard to find, but Mohawk will have the transparent toner.

GL

Chas

BTW thanks for the 5-wire cable tip. I have been looking for some time for a cable for a Browning-Drake Resistance coupled kit set...

[radiorich]

Hello Chase,
I first bought that 5wire cable from Grand Brass lamp parts back a couple years ago but need to pull my General Electric chassis to install it when I restored my chassis I used PVC wire to replace all the rubber wire .

mike Gloss finish would look nice but I have used Semi Gloss finish too .

Sincerely Richard

[morzh]

Chas,

I literally found this cable 5 minutes after I thought of changing it.
I simply went up the stairs, from the workshop to my computer, typed in Google "cloth-covered brown 5-wire cable" and it gave me the picture of that very wire.
I had no idea about this company and its product.

[Chas]

Shellac or lacquer, the finish performance is practically the same. Both can be built up to enhance grain depth, both can be tinted, both can have an incredible gloss. The one difference if the coating has flattening agent, silica, the finish will for ever be flat or semi-gloss and cannot ever shine. Such a coating will also dull the effect of the grain which is to "flash" the cell structure of the wood so as to make it appear to have glint to the finish.

Either shellac or Lacquer can be "de-glossed" mechanically with powdered (fine) pumice and oil polishing giving that semi-gloss look but still revealing the flash of grain. Levels of gloss can be achieved by polishing with rotten stone and oil. Furniture makers often highlighted finishes by polishing selected areas of wear to enhance authenticity by selectively polishing with rottenstone in larger areas to give the effect of owner care but being able only to reach those large areas with the polish.

Sixty years ago, I re-finished some seven battery radio using cabinet rubbing varnish. I did not have access to lacquer and did not have skills and materials to properly do a shellac finish. To this day the hand rubbed varnish finish looks the same. Slight crazing is evident so there is an aged look.

Philco 70, Thompson Neutrodyne, Splitdorf, a Browning-Drake home-brew in oak, a FADA Neutrodyne kit with a white camphor panel. A Malone-Lemon Neutrodyne with an ebony finish over solid walnut despite the dark wood it still flashes in sunlight. Themyodyne 1-tube kit, A Grebe Syncrophase, even a Music Master wood bell horn. which had extensive re-glue of the wooden petals and hand electroplating of the horn neck. However, the polymerized varnish is brittle and one of the sets has a tiny chip in the finish. Varnish is not as rugged and cannot be "repaired" like Shellac or Lacquer. Yet Shellac is softer and can take minor knock, Lacquer is a little tougher over all but varnish is alcohol proof. That is the choice of Luthiers.

YMMV

Chas

[radiorich]

Hello mike,
If I would only known instead keep the secret I would posted about is few years ago !
Sincerely Richard

[MrFixr55]

I would try to duplicate the finish that was under the 3 tube island upon disassembly and cleaning. One minor detail is the brass (?) grommets where visible wires pass through the board (3 tube island, etc.). Did you push them out prior to finishing the board? What did AK do upon original manufacture?

[morzh]

I will leave the grommets be. They are the same color, and whatever film forms on them, I will be able to puncture it easily.
I actually asked the question with a suggestion to plug them with pieces of wood toothpicks if they think the lacquer would form a plug and not a thin film.
They just said they will make sure the grommets are not plugged.

[morzh]

O this is the way I made the tires for the tuning caps.
I had no luck finding something that looks like what it should look like and works.

I also am not sure if the tire should engage when the knob is pushed in, in order to the dial to be able to rotate freely otherwise for fast tuning, or stay engaged all the time.

All grommets that look similar and could be cur in hald to resemble the original are either too thick, or too thin, or have the inner hole diameter too large.
I liteerally spent hours on the web.

Here's what I came up with eventually.

I bought rubber bushings ID=7mm OD=16mm  Height =8mm, made by PATIKIL, sold on Amazon. This is the only size that is close enough.
The original tire (dried up) is ID 8mm OD 16mm Height 5mm. 

So then I took the bushings to a grinding wheel and just took 1mm off first. Then used sandpaper to round the edges. 
This proved too much. When the screw holding the knob was tightened, the bushing pressed onto the dial so much the latter could barely be turned.
So I took another 1.5mm, again, took some of the walls at an angle to make a cone, and then smoother the edges with sandpaper.

Works fine. One is engaged all tthe time but rotates almost freely; the other two need to be lightly pressed upon, and this is my understanding this is how it should be in order to be able to fast-tune.


This is the bushing
   

This is the machined bushing.
   

This is the knob and the tire assembled.
   

And the whole thing
   

[MrFixr55]

Looking really nice! The verniers engage only when pushed in; they were used on all the other early A-K radios including the Model 20, 30 and 40 series and possibly later. I think that the friction material was cork, but your fix certainly will work!

[morzh]

So, yesterday I picked up the refinished board. Here it is.
Semi-gloss finished.
The burnmarks have been there before. Probably factory defect. Will be covered by the parts under which they were found.

Tomorrow will start putting parts back.



   
   

[Arran]

Mike;
I hope they didn't waste too much time in trying to get the burn marks out. Even wood bleach has a tough time on those.
Regards
Arran

[morzh]

They didn't. I specifically told them not to, as this is concealed under the potentiometer.

[radiorich]

Hello mike,
It really turned out very nice !

Sincerely Richard

[MrFixr55]

Morzh, sorry, I missed the post asking if the AK10 could drive the Model E speaker.

I believe that the Model E speaker was introduced in around 1927 or so and is more commonly associated with AC sets like the Model 36 or very commonly with the Model 40 and was built into the "Stove" models. It was also likely used with sets like the model 35 which had provisions for biasing the output stage so tubes like that 112 or 71A could be used. It is kind of an anachronism, as the Model E was introduced in about 1927 and the A-K breadboard set production ended in 1924 or 1925

However, here is a page from Atwater Kent.net stating that for a speaker, that any horn or magnetic type speaker can be used:

http://atwater-kent.net/breadboards/page2-3.jpg

Horn and "magnetic" speakers had similar impedances, around 1KOhm or so. However, I assume that magnetic speakers required more power. for battery sets, speakers or headphones were connected directly between the plate of the output tube and B+. For AC sets or sets using "Power" tubes like the 112 or 71A, LC coupling or, in the case of the Radiola 17, transformer coupling was used.

I was not able to find any documentation on the model E but here is an instruction manual for the Radiola 100-A speaker, also Ca 1927:

http://radiolaville.com/graphics/docs/ra...iption.pdf

Hope this helps.