Since first laying eyes on Chambers' visual tragedy many years ago, I've been loath to grant the Model D any respect.  Aesthetically, if such a word even applies, I consider it the Edsel of the Chambers brand.  After decades of minimal changes to a warm, timeless design, the folks at Chambers seem to have taken a flying leap into steely cold Bauhaus pop.  Well actually, likely NOT the folks at Chambers: my friend Todd White, keeper of the Chambers Stove Lovers website, writes that Rangaire had taken over by 1964.  So the new owners probably felt the need to make their mark.  Just like dogs make their marks on trees, if you ask me. 

There might be uglier stoves out there, but considering how nice looking and un-gimmicky Chambers stoves had been for so many years, even the plainest model D gives me a headache.  Then there's the top of the line Stainless Steel and Ivory Imperial shown here, trimmed with airbrushed Avocado.  It simply shocks the senses.  The squared structure, multiple facets of varying colors and surfaces, yards of channel trim, and wacko, uncomfortable handles on the broiler, oven door and service cabinet.  Hard to keep clean, unpleasant to touch...  And the looks - like fingernails scraping on chalkboard, while chugging a castor oil martini!
The many years and service calls that have passed since that first encounter have somewhat tempered my revulsion.  They are still ugly - no yielding on that - but I realize that the basic concept and layout remains true to that of the A, B/Z, and C.  While Rangaire had obviously decided that a visual update was needed, it seems they were confident enough in the unique character and value of their acquisition to leave the basics alone.  Let's see:  I believe that the model A originates in the early 1920's, when American farms still had way more horses pulling plows than tractors.  40 years later with the model D, we are blasting off to the moon, yet the Chambers stove had not been significantly altered, avoiding the yearly "ALL NEW!" marketing path followed by every other appliance (and car) manufacturer for decades.  Not abandoning Cooking With the Gas Turned Off (CWTGTO)?:  gotta give Rangair some credit on that account.

Also, I must say that the D's oven safety system is quite impressive, in terms of functionality and well-built components.  

The most significant technical change of the D from the C is also it's most dubious characteristic: incorporation of the Auto Timer, designed to automatically turn the oven on and off at pre-selected times.  Why dubious?  First, the Auto Timer only applies to conventional oven use:  it cannot be used for CWTGTO, the primary feature setting Chambers apart from all others.  That's like putting an electric motor on a Harley.  Secondly, my investigations of the D's Auto Timer reveal that Chambers now shared a safety flaw that had previously been the sole provence of all lesser makes with similar systems.  From this comes my obligatory warning to Chambers D clients:

DANGER:  If an electrical power outage occurs with the ThermoStat dial turned on and an "Auto Start" time selected, the loss of power to the Heater Valve Solenoid will open the Heater Valve, prematurely turning the oven on.  Similarly, since electricity is required to close the Heater Valve (which turns off the oven when the ThermoStat dial is turned on),  a power outage while "Auto Stop" is engaged prevents  the oven from being turned off at a selected "Stop" time. 

Yeah, sounds scary.  But for current and wannabe D owners, it's hardly a deal killer.  First of all, the chances of a power outage while using the Auto Timer are slim, though not impossible.  Secondly, by not using the stupidly irrelevant Auto Timer system, the scary irrelevant problem is avoided altogether.   An ancienttechnology - used on other makes since the early 40's - practically useless to anyone sold on the CWTGTO pillar of Chambers marketing.  Why it suddenly appeared on a Chambers in the 60's is anybody's guess. Rangaire probably wanted to attract potential purchasers who were used to this feature on other brands they had owned.  Why hadn't Chambers incorporated Auto Timers earlier?  Here's a quote from a 1940's Chambers brochure that reveals their confident and reasoned wisdom:

(Cooking With The Gas Turned Off) is a feature of Chambers Ranges that is not to be confused with automatic timing devices becoming more widely advertised. There is not much logic in buying a fine refrigerator to preserve food and then leaving perishables in a room tempera­ture oven where the heat is not set to come on until 3:00 or 4:00 o'clock in the after­noon. With the remarkable Chambers method, no bacteria can develop because food starts to cook before you leave home; the cooking Finishes on retained heat and the Chambers oven and Thermowell act as sealed warming closets until it suits your con­venience to serve the meal. Cook the food first - the Chambers way - and play safe!

Ha!  Rangair thought it knew better.  Looking back, their confusion - or cluelessness - made evident by the Model D, was the first, clear indication of the decline of the Chambers brand. 

Despite it's bizarre looks, increased complexity and ridiculous Auto Timer, the D for the most part inherited the same well thought-out functionality and build quality as previous iterations. Chambers purists may scoff at the fact that D's have electric controls (for the oven, if the Auto Timer is utilized), but beneath this and the D's visual changes, the heart of the same old Chambers is still beating.  Sure, the oven's Auto Timer operation does require electricity, but its CWTGTO and conventional operations function safely and normally, by choice when not using the Auto Timer, or by default in an electrical outage.
Would I have a D in my kitchen?  Not a snowball's chance in a pre-heated ThermoWell,  but if I run across one whose owner has requested some TLC, I promise to be polite and stifle any opinions I may have about their baby's looks.

TECH HINT:  Has your Model D oven stopped working?  IE, does it refuse to light when you turn the dial on?  If so, first be sure your oven's pilot is lit.  If it is, there's a good chance your Auto Timer is malfunctioning.   Try unplugging the stove's cord from the electrical outlet.  You should hear an immediate "click" from inside the service cabinet.  Unplugging the cord de-powers the Auto Timer and puts it into default "Manual" mode, which opens a valve between the oven thermostat and oven burner.  A handy remedy when the Auto Timer switches start malfunctioning.