Todays Crescent Dishwashers

[jetcone]

Doctrine is so Kewl!

At the last Restaurant Show here in Boston, Hobart had on display one of these machines all restored from 1919! It had the bottom arm but I don't remember it having the top arm. But it shocked me when I looked inside and saw the same wash arm as in my KDS-14!! The racks were wooden, the guy there told me they were made of Spruce as that was durable and didn't chip the china.
There were a lot of copper parts inside that were polished to the hilt too!
It was a beautiful machine to look at.


At The Magic Pan by that time Hobart had changed the spray arm to a narrower tubular arm with bolted nozzles mounted across it to the ends. Not like the earlier UM machines nor the 10-14's series.

The brochure tells about the wide slit design of the wash arm, something I always wanted to understand where it came from!

"Compare this heavy duty nozzle with the average slit or spray hole... Notice the width and length of the opening....the unobstructed path of the water.... the volume of the torrent that strikes each soiled dish with full force.
There...<span style="font-family: 'comic sans ms', sans-serif;">and there only...</span><span style="font-family: 'times new roman', times;">the jets expend their force....undermining the dirt...lifting it from every flat surface and crevice...stripping and scrubbing it away."</span>

 

<span style="font-family: 'times new roman', times;">LOVE THAT!!
 </span>

[this post was last edited: 7/1/2012-09:03]

 

[labboy]

Love this...

Great document in the Daily Doctrine. Love the graphics on the front and back cover and all the detail in this document.

Thanks for posting!

Bob

 

[stevet]

Just had to get a copy!

I have seen the machine you speak of Jon and am always amazed to see other technicians' reactions to it. As if we just started making dishwashers a week before we hired them! Sadly, they are not taught much about the history of design of Hobart machines like I was in Warewashing School. I learned about the original AM'S, LM'S and SM"s which they don't even have hanging around for the techs to even see!
Yes the Copper machine is a thing of true beauty and so is this brochure.
I downloaded a copy of it and enjoyed reading it. I go back originally to 1979 with Hobart and can remember very well some if the design elements of these Crescent Machines being carried over to later designs. Where other companies continued the chain drive conveyors, Hobart went to a reciprocating rack drive still using the speed reducer shown in the brochure which was remounted on the end of one of the pump motors thus driving the pump and the conveyor with a single motor.
Can you imagine if the KDS 15 had one of those 4 way cast iron washarms in it! If they could get the big blue arm to work in a small chamber I bet the 4 way would have worked too!

Thanks, Robert for providing this look into the past

 

[toploader55]

Sequel...

I just received some Old Spec Sheets which will show the Progression of Hobart Models.

 

[jetcone]

OMG Stevet

I can't imagine the force a 4 arm would have inside my 14!! WOW!

It says they were mounted on ball bearings, Stevet do you know how they did that against all that caustic dish water?? Were they marine bearings that used water for lubrication?

 

 

 

[toploader55]

Jon...

Look at the Thread I put up on Early Hobart Dishwashers. The CCM-2 has a Phantom Sketch. Look at the Top Wash Arm . The Ball Bearing Assy. is Externally Mounted.

 

[whirlykenmore78]

An example of one of Hobarts revisions of the Crescent arm

This is from a Late 60's/very early 70's AM-9-T2. Notice how many design principles were kept. The latest model I've seen with these arms is the AM-11. The AM series underwent a whole redesign when the AM-12 came out.

 

[stevet]

Thanks Eddie

For all the pics you have posted. Are you sure you never worked for Hobart yourself? It is easy to see how they set the standard for machines and performance.
I cannot tell you how few guys in my own office have never seen some of the classic machines. There are still a few of the old C-Line machines in the Orlando area, many are still at Epcot which was heavily equipped with Hobart products maybe because Hobart was owned by Dart and Kraft and Kraft was a major exhibitor at Epcot when it first opened.

 

[toploader55]

Hey Steve.

I wish I did work for Hobart back in the day.

I still can't believe the restaurant I work at took out a perfectly working UM series out of the bar and replaced it with a LX. The LX breaks down at least 3-4 times in the 6 months we're open. While the UM NEVER broke down.

 

[jetcone]

Ooo Eddie

where is that UM now sitting??

jon

I see the ghost view now, Eddie, thank you. The ball bearings are outside the spray tub and the wash arm must depend through the top supported by the bearing and the water must be injected into the arm below the top of the machine. So the ball bearing never sees the wash liquor.

Thanks

 

[toploader55]

Hi Jon.

Yes, Exactly. The water is fed into the wash arm. The shaft that the wash arm is attached to has the Ball Bearing Assy outside on the top. The AM series upper wash arm is the same set up.

I still can't get over the size of the motors on the CM series

 

[jetcone]

Well Eddie

if those were permanent magnet motors that might explain the size. Hobart may have switched to AC induction motors in the 50's which would make them more powerful and smaller.

Stevet-did Hobart use permanent magnet motors in their machines?

 

[toploader55]

Where...

Is Stevet ???

Calling Dr. Stevet... Calling Dr. Stevet...

Paging... Dr. Stevet... Paging Dr. Stevet...

Hmmmmmmmmmmmmmmm..........

 

[toploader55]

Jon,

I have no idea about Permanent Magnet Motors. But as I type, my imagination is making sense right now. Common sense is telling me about it.

As I recall, when those CM machines fired up, All you heard was the motor start and then just the water being sprayed though the Wash Arms. Vaguely any Motor noise at all.

Hey... Wheres Melvin been (supremewhirlpool) ??? He's the Triple Phase Grand Kahuna.

I love reading his post about conversions.

 

[tolivac]

PM motor

Actually for their size and weight-PM motors pack more Horsepower than induction ones-but PM motors MUST work from DC.If you try to operate a PM motor from AC-it will burn up.the motors in those dishwashers were large frame induction motors meant for heavy continous duty under hot, adverse conditions found in a dishwashing area.Otherwards for their HP rating they were built on a larger frame than for a standard duty induction motor of the same HP rating.This was also done in industrial sectors,too.The PM motor is what made cordless tools and for more efficient,and lighter weight corded tools and appliances.And solid state rectifiers helpted in this,toften the rectifier is built right into the PM motor-usually in the brush end of the frame-that is a minor disadvantage of PM motors-they do use brushes-but their lower speeds(often same as induction motors) make the brushes last a long time-often the life of the motor.

 

[jetcone]

Interesting info on the PM

motors Rex! Yes when I think of it our Hobarts ran almost the whole shift and that meant the whole evening shift too for 12 hours continuous operation. So they would have to be very durable motors do to that!

 

[tolivac]

I have seen similar oversize frame induction motors on older woodworking and metalworking tools.Ie-a 5Hp motor built on a 10hp frame.And those motors lasted thru years of training people-high school guys-how to use tools,and the abuse they went thru-too!And the oversize motors were easily rebuilt.