# New Departure Model A Questions



## Ed Minas (Aug 8, 2018)

I have been putting Model A’s on my TOC riders.  The other day I was riding and the hub basically exploded.  All of the sudden when I stopped peddling and applied back pressure to brake the cones became loose and the wheel was wobbly.  After taking a close look I thought this would not have happened had there been jam nuts between the cones and the rear stays on one side and a locking nut between the brake arm and the rear stay on the other side.    Here is my question.  Should there be thin jam nuts to lock the cones and brake arm in place?  If not what keeps the whole mess from not backing out like mine did.   I found a parts list for the Model A but not an exploded diagram.  Any help and expertise on the Model A Hub would grateful appreciated.


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## bikiba (Aug 8, 2018)

https://www.sheldonbrown.com/coaster-brakes/new-departure.html

do you have an A13? I believe tht wld prevent the cones from loosening.


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## Ed Minas (Aug 8, 2018)

bikiba said:


> https://www.sheldonbrown.com/coaster-brakes/new-departure.html
> 
> do you have an A13? I believe tht wld prevent the cones from loosening.



I saw that in parts list but wasn’t sure if that was the nut that is used on the outside of the stays to hold the axle in place on the frame.  That is my conundrum


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## bikiba (Aug 9, 2018)

ah i see - you think that might be the outer nut. Hmmm. I see your point. On all my model As come to think of it i dont remember an inner nut. i dont have any left. Im sure someone on the site has the answer


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## mickeyc (Aug 9, 2018)

The part #A13 is the thin nut that holds the brake arm in place.  Definitely need that.


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## Archie Sturmer (Aug 9, 2018)

When somebody says "Axle nut" does one then usually think "lock nut".

I recall wondering the same question; I believe that the catalog pictures showed the parts disassembled, and laid flat, but not a break-down type or isometric diagram.  Sometimes more insightful pictures may be found at the patent office; often a product may be the result of more than one design patent.

The 1902/03 Albert Fenimore Rockwell patent # 745,524 figures show what look like dish-shaped washers (socket washers) on both sides, next to the brake arm (L) and the adjusting cone (R).  The patent describes that loosening the axle nuts alone, without disconnecting the brake arm, would allow for the parts (brake & cone) to be loosened or tightened; it further describes that as an "important" feature.  [No mention of additional locknuts to also be loosened].

Another 1910 ND design patent (MacGuyer) states that "Preferably the ends of the axle receive lock nuts to prevent displacement of the cone and brake plate".  Wonder how they figured that out.  When we use an old design, unimproved, sometimes we are stuck with their original faults.

https://thecabe.com/forum/threads/c...g-project-need-everyones-help-pre-1933.34160/


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## Ed Minas (Aug 9, 2018)

Wow I am speechless.  Everyone who chimed in has been super helpful.  Believe or not Scott McCaskey sells the dished washer that fits against the brake arm and I have purchased the same, now all I need is the thin nut to scure everything (item A13).  I wonder if the nut is the same for C and D hubs?  That might make easier to find some.
 Thanks again.


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## Archie Sturmer (Aug 10, 2018)

There are no "thin" nuts in the ND catalog picture; what we can see depicted are the washers (round sides) and "Axle Nuts" (six sided).


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## Ed Minas (Aug 10, 2018)

Thanks Archie, great picture. Does the brake arm just flop loosely until the hub is bolted between the stays?   Any idea why my hub separated (exploded) when I applied braking pressure?


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## Archie Sturmer (Aug 10, 2018)

Yes, the brake arm could flop loosely, if it were not otherwise secured.  Note that only one cone is threaded to the axle in this design, that is the adjusting cone on the right hand drive side.  The other element that is threaded to the axle is the brake assembly.  The left cone, which is called a brake actuator, is not quite a perfect cone, perhaps more of a pulley-shaped wheel, shaped so that the ball bearings would move L-R with the moving 'cone'.



No, not sure about your case of the "exploded" hub; were any parts damaged or broken inside, or just the loosening as you described.
If the engaging teeth between the brake-arm to brake-plate (threaded) were loose or worn, to allow the brake to turn (forward with the hub/wheel), then that could cause the axle to turn, and that cause the RHS cone and axle nut to loosen, allowing for even more loosening, slippage, and turning.


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## Ed Minas (Aug 12, 2018)

This is fascinating.  I am going to take another look at the assembly.  Thanks again Archie


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## dnc1 (Aug 12, 2018)

So, do I need the 'dished' washers for this?
(I realise I need a better sprocket!).....









Please note that the large knurled-edge washers are for fitment to a  'National' frame.


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## Ed Minas (Aug 14, 2018)

From what I know I would say yes.  What I find very interesting though is you have the thin nut holding the brake arm in place.  That nut seems to be the subject of much discussion and some controversy


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## gkeep (Aug 15, 2018)

From the hub thread posted above.
This NOS in the box 1908 does not appear to have the thin nut on the brake arm side.


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## bricycle (Aug 15, 2018)

all the many A's I have had never had a lock nut (always thought that was goofy, but then I'm goofy).


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## dnc1 (Aug 15, 2018)

Ed Minas said:


> From what I know I would say yes.  What I find very interesting though is you have the thin nut holding the brake arm in place.  That nut seems to be the subject of much discussion and some controversy



So do you think perhaps, the locknut on my example is a later owners modification to ameliorate the aforementioned 'exploding' hub situation? Or a factory update during the hubs production period?
Nice photo @gkeep, nice to see an unused, very original item.


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## dnc1 (Aug 15, 2018)

Also, can anyone inform me as to whether sprockets are easily available?
Are there any differences to look out for to identify a model 'A"' sprocket?
These hubs are pretty uncommon over here, so any advice is greatly appreciated, thanks.


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## gkeep (Aug 15, 2018)

I had to replace my shark toothed sprocket before I could ride the bike. The standard skip tooth sprockets that everyone has for sale here fit just fine. The bike came with a 9 tooth rear, I should have gone with a larger rear to lower the gearing, I'm getting old...


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## dnc1 (Aug 16, 2018)

gkeep said:


> I had to replace my shark toothed sprocket before I could ride the bike. The standard skip tooth sprockets that everyone has for sale here fit just fine. The bike came with a 9 tooth rear, I should have gone with a larger rear to lower the gearing, I'm getting old...
> 
> View attachment 853252



Thanks!


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## Ed Minas (Aug 25, 2018)

Well it is anybody’s guess as to a nut was added as the design evolved but, am certain the the hub would not have come apart if one was present.


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