News:

"The phone is a remarkably complex, simple device,
and very rarely ever needs repairs, once you fix them." - Dan/Panther

Main Menu

Now the Story Can be Told - 1949 WECo 500 Set

Started by Dan/Panther, March 20, 2010, 11:08:11 PM

Previous topic - Next topic

Dan/Panther

The original Material is very brittle I assume it was Tenite. I had anticipated several materials, thought of round stock the decided a flat sheet would be easier to handle as my lathe will not go up to the 3" need to turn the part. However using a faceplate with a piece of flat sheet attached to it, would make the job much easier. the good thing about this is all of the hard portions of the dial are hidden, the easy parts finger holes outside edges etc, are the easiest parts to make.
Every piece of the original phone is being carefully handled and stored. The bask cover for the dial is very warped and the gears rub against it. Being tenite, to straighten it would surely end up damaging it, so I will use the method used by Radio restorers to fabricate new dial covers for radios that have yellowed or cracked after years of heat exposure. Making a wooden mock up, and .020" polycarbonate sheet, heated then formed over the mock up works exceptionally well and makes new dial faces almost undetectable, as originals.
back to the finger wheel material, I think ABS is a good choice, it is easy to machine, is very durable, comes in black, and as far as I know can be polished up to look very bright.
D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

JorgeAmely

D/P:

The tough part will be the rectangular notches into which the card ring snaps into. Have you thought of a method to do those?

Jorge

dencins

#257
I agree with ABS as a substitute.

If you do use Tenite you can find the machining guidelines from Eastman Kodak in this brochure:

http://www.eastman.com/Literature_Center/P/PP110.pdf

You can find the extrusion temperatures here:

http://www.eastman.com/Literature_Center/P/PP108.pdf

Just for reference Tenite II is fiberglass filled Cellulose Acetate Butyrate.

If you want to flatten the back cover you can heat it to pliable (before melting point) then put weight on it.  Tenite is amorphous so it warps less than a crytstaline plastic.  Once it is soft, flattened and cooled, it will maintain the new shape (crystaline tries to go back to the original shape).  Tenite melting point is 284 degrees Farenheit so you would want to stay at least 30 to 40 degrees below that.  

I soften plastic in a toaster oven but I judge the temperature using an oven thermometer.  Toaster ovens overheat then cool to get an avarage temperature.  I use an oven thermometer to make sure the maximum is not too hot.  Also make sure it is on a flat surface in the oven - not directly on the rack or you will get lines.  I also put the part on Reynolds Release aluminum foil so it does not stick to the surface.

I like the radio restorers method using wood and sheet covering.  I will file that for future reference.

Dennis

 

Dan/Panther

#258
Jorge;
I think I will most likely use a round hole, then square file to shape.

Dennis;
The back cover for the dial is very warped and already has a hairline crack, I don't think I will even try to straighten it, Even if I could it's yellowed to the point that it's hard to see through. Polycarb sheet is crystal clear. I'll post a couple photos on the thread to show the mold. With the polycarb sheet, you just wait until it droops. Then it's ready.
Those two articles are keepers. I didn't know Eastman made Tenite, but now it makes sense. Eastman Acetate movie film shrinks after prolonged exposure to heat and improper storage, causing a rare movie not to be able to be projected any longer.
They must not have a very good testing system.
D/P
Gheez, I didn't even realize until after I posted the response I was in the thread.
Below are the photos for the polycarbonite method of dial face covers.
You place the lower part of the first photo onto a flat metal piece, about the same size as the upper part of the mold. Then you cut a polycarb sheet about 1" all around larger than the bottom part of the mold. Place that into the toaster oven on top of the sheet metal and lower portion of the mold. When the poly sheet droops, quickly pull out of the toaster oven and press the upper portion of the mold onto the part you just pulled out of the oven. Hold in place for about 30 seconds. Remove and trim the excess poly sheet. A very good replacement.
The third photo shows the results of this mold, on a 1937 RCA 7T-1 Tombstone radio.

D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

rp2813

Well D/P, I just came across the threads dealing with your fantastic find, and absolutely feel that this rare item has landed in very capable hands.  I can only imagine how elated you are over this!

It's interesting that the bezel's numbers and letters appear to be the later injection style.  Looking at the bezel on my 10/50, the painted characters are more delicate looking, with the "P" and "R" not nearly as filled-in as on an injected type.  And on your set, you have a round letter "O" rather than the elongated numeral "0" at the 10th position.  It seems that with a set like yours, Bell Labs was trying out all of its concepts for the 500, and maybe didn't get the production fine tuned to implement everything at launch, such as the injection type of bezel which showed up in production a little later on.  It's also interesting that your bezel has the dots.  I thought the early trial phones didn't have the dots, which caused some misdialing, and so the dots were added to remedy that situation.

I agree with others who have said your set would have had the T1/U1 elements in a G1 handset.  IMO, Bell Labs would have been trialing those elements along with the rest of the set, and as others have stated, the F1/HA1 elements weren't designed to work with the 500's circuitry.

I have mixed feelings about a clear case vs. a black one.  I'd kind of want this phone to look like it did when it was sent off to be trialed. 

I suspect you'll find the correct early type G1 handset without much trouble, although I doubt it will be dated 1948 or 49.  I think maybe we've learned here that the seriously early 500's won't have the type of dating we're used to seeing on production sets.

CONGRATULATIONS!

Ralph
Ralph

Dan/Panther

Ralph;
Thanks for the kind words. It has been a fun filled journey so far. I'm thankful for all of the very much needed and appreciated advice and parts, and help.
I hope to do this justice and I'm not hurry anything.
D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

Jim Stettler

Quote from: rp2813 on March 29, 2010, 02:19:34 PM
I thought the early trial phones didn't have the dots, which caused some misdialing, and so the dots were added to remedy that situation.


CONGRATULATIONS!

Ralph

Ralph,
The dots are a very good point. I would guess the '48's didn't have dot's (at first) and the '49's did.


They original 50 '48 sets were used w/ 300 field trial users (6 different trials?) . I wonder when they added the dots. I would think the problem became apparenty early on in the trials. I wouldn't be surprised if the dots got added during the '48 field trials.
Has anyone come across a photo w/o dots?
Jim
You live, You learn,
You die, you forget it all.

bwanna

tied w/phones in old movies at 261 posts. i wanted to be the one to put this one in the lead :P
donna

Dennis Markham

I think I read somewhere (it may have been in Ralph Meyer's book) that the dots originated with the 500 sets once the numbers were located outside of the finger holes.  The numbers were located outside the holes to that the user could eyeball the next number while the dial was returning.  The dots were there so the user could tell the returning wheel had stopped.  I'll get that book out and see if I can find that section.  It was my understanding that the dial bezels always had dots beneath the holes. 

I meant to look this up earlier today and I got sidetracked.  But that book is the only one I have.  Perhaps someone else has a reference document on this.


Dan/Panther

#264
I thought the dots were a target to aim your finger at.
I'm still a little, no a lot confused about the clear or black plungers, round top black, or flat top clear ? Two pictures I've seen shows both with O/Operator/Z, each with different plungers.
My train of thought tells me the clear was a older version, and changed to the Black, which would be production. I don't think practice was do something then go back to previous. I think the progression was Clear, Black, then finally Black. Not Black, Clear, back to black. My logic in thinking is this, IF someone had the power to change from Black to clear, and consensus was to go to clear, I don't think anyone would have argued to change it back, politics you know.
D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

Dennis Markham

The black ones are Bakelite, I believe.  The clear ones appear to be Lucite.  Which is cheaper?

Dan/Panther

I would guess bakelite was cheaper, Lucite pointed to the future. The buck wins though.
D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson

Dennis Markham

In Old Time-Telephones! by Ralph Meyer, Chapter 14 beginning on page 86 it covers the Western Electric 500-type Telephones.  

Beginning on the bottom of page 87 he writes:

    The dial, which was part of the Dreyfuss design, was arranged to improve dialing accuracy and speed.  To accomplish this, the numbers and letters were moved outside of the fingerwheel where they would no longer be obscured by portions of the wheel itself.  In principle, a dialer could take aim at the next number while the fingerwheel was still moving, thus accelerating the whole dialing process (Prescott 1952; Donovan 1991).  Ironically, extensive tests with the early design of this type showed that the dialing time was actually slower than with the older 302 set (Black and Cunningham1954; Flinchum 1997, 100-102).  From observiing participants in the tests, it was found that the time loss occurred at the end of the period when the fingerwheel was returning to it's rest position.  The dialer was slow to recognize when the dial had come to rest, because no frame of reference was provided by the black fingerwheel revolving over an all black background.  This was remedied by placing a white dot  at the center of each finger hole so the dialer could tell when the rotation had stopped.

So based on this, there was a trial bezel with no dots.  It is unknown if any sets were released that way based on this report but it appears to have been remedied while in the test phase of the model.


   

McHeath

I agree with you D/P that the clear plungers are probably the older of the two, and for the same reasons that you argue.  

Do the hookswitches push the plungers up on a standard 500 shell when you fit it on?  Wonder if they changed the design so that it would be stronger?  A flat metal bar seems like it would be easier to bend and lose tension than the sideways metal bar of the standard design.  

Any word from Paul F about the phone yet?

Dan/Panther

I was just kidding about using the dot to aim at, but at least it appears to have been a consideration.
D/P

The More People I meet, The More I Love, and MISS My Dog.  Dan Robinson