Two questions RE Bulova 16AB Movement.

[Fissile]

Hello, everyone.  

I'm just starting in this fascinating hobby.  I rate my skills as a half-step above noob.  I recently purchased a broken Bulova 16AB movement on eBay for $26 utilizing my expert sniper skills...my apologies to any of you gals/guys whom may have been bidding on this hunk-o-junk.    The 16AB appears to be a standard Unitas 6497 but I have not seen the Unitas mark in the usual place (only partly disassembled at this point).   Like I said, it seems to be a 6497 but it does have on notable difference, instead of the usual Incabloc found on these movements this has got a Kif.   

These are my two questions: 

1) When I removed the dial, I found two dial washers installed in reverse orientation.   I've never encountered this before.  Is this how some watches came from the factory, or does anyone think this may have been some half-a**ed repair attempt? 

2) When I removed the hands the cannon pinion popped off as well.  Hmmm.   I'm guessing I will be ordering a new cannon pinion and/or center wheel.   I checked with the usual suspects, and they offer 3 different cannon pinion heights for the 6497/8.   I'm really not sure how to measure the cannon pinion height.   Do I measure the overall height of the cannon pinion, or just the shaft (no dirty pun intended)?  Having worked on cars since I was 14 years of age, I'm not a fan of 'repairing' broken stuff by firing the parts 'cannon' at it (pun intended).  

Anyway, if I can get this bowel-movement running, my plan is to install it in a Panerai-esque case I purchased on Ali Express for $32 Murican (delivered).   Any info you folks can provide will be greatly appreciated.  

[JohnC]

Cannon pinion can be tightened using a staking tool or cannon pinion tightener. Described in Fried's Watch Repairer's Manual, a great reference book to have around.

[Fissile]

32 minutes ago, JohnC said:

Cannon pinion can be tightened using a staking tool or cannon pinion tightener. Described in Fried's Watch Repairer's Manual, a great reference book to have around.

Thanks for your answer.  Yes, I know the cannon pinion can be tightened.   Unfortunately, that doesn't answer my question regarding how to properly measure the height of the cannon pinion.  

[watchweasol]

Hi  The unitas 6497  brings up the ETA6497 and as no tech seems to be available for the Unitas/UT and everything equates to the ETA movement .   from the drawings (attached) there are three heights measured from top to bottom of,     2.65        3.00     3.15           so in answer to your question it would look like you measure the total height of the canon pinion         Hope all this is some use to you        cheers                        Unitas 6497-1, 6498-1 (1).pdf

Unitas 6497-2, 6498-2 (2).pdf

[Plato]

2 hours ago, Fissile said:

I'm guessing I will be ordering a new cannon pinion and/or center wheel.   I checked with the usual suspects, and they offer 3 different cannon pinion heights for the 6497/8

You can service and get the watch running before ordering these parts, you might need others.

[watchweasol]

Have a look at Ranff.de unitas 9647 for further details and information.

[Fissile]

1 hour ago, Plato said:

You can service and get the watch running before ordering these parts, you might need others.

That's a good idea.  Now that I look at this thing a bit closer it's clear there are some differences between this and the ETA 6497-1 even though it measures the same diameter as the ETA @ 36.6mm

The first picture is from the bridge side.   It appears to be a bog standard 6497, the obvious exceptions are the shock system (this uses Kif and ETA uses Incabloc) and the fact that this uses a pallet cock instead of the ETA's pallet bridge. 

Second picture is from the dial side.  That keyless works is definitely not like the ETA.  The setting spring and setting lever are very different.  The setting wheel layout is also different.  The slot on the setting lever screw is totally buggered and the stem is broken off in the movement.  

What have I got myself into?

[Fissile]

Well, I did some research and found out that the movement I purchased is NOT a Unitas 6497, it is a Unitas 497, which is an older version.   This particular movement was made in 1965.   Now I need to take it apart completely and find out why it doesn't run. 

[JohnR725]

14 hours ago, Fissile said:

Bulova 16AB movement on eBay

http://cgi.julesborel.com/cgi-bin/matcgi2?ref=BUL_16AB

4 hours ago, Fissile said:

Well, I did some research and found out that the movement I purchased is NOT a Unitas 6497, it is a Unitas 497, which is an older version.

Looks like your research be doing better than the material house did? Found your movement above parts list including the Canon pinion height. Normally if you click on a part it give you everything Including a cross references to, and they don't seem to think cross to anything?

Although it Does look a lot like the 497 in the picture below except the balance wheel jewels?

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&0&2uswk&Unitas_497

Then I did find You a parts list.

Bulova_Bulova 16AB.pdf

Edited November 12, 2021 by JohnR725

[JohnR725]

4 hours ago, Fissile said:

Now I need to take it apart completely and find out why it doesn't run. 

Looking at your pictures again one of things that bothers me is look where the stud holder is? Typically get find the regulator in that position and the stud holder should be moved back considerably. But in need to look at whether the watch visually is in beat and put that where it's supposed to be it may be somebody is bumped that it may be grossly out of beat or it may just be fine. The understand what I mean by this look at the link for the 694 I have above and you'll notice that the stud is in a different location

[watchweasol]

Hi   Unitas 497 attached  to be able yo make a comparison with JohnR725's  Bulova 16 sheet

Unitas 285, 497, 498, 6500 (1).pdf

[Klassiker]

Going back to your original question about the two dial washers, I wouldn't be concerned. It is a valid method of increasing the distance over which a disc spring acts, without increasing the rate, or taking up play in other words. The orientation is the key. The other way round you get the same deflection as a single spring, but double the rate.

[Fissile]

17 hours ago, JohnR725 said:

Looking at your pictures again one of things that bothers me is look where the stud holder is? Typically get find the regulator in that position and the stud holder should be moved back considerably. But in need to look at whether the watch visually is in beat and put that where it's supposed to be it may be somebody is bumped that it may be grossly out of beat or it may just be fine. The understand what I mean by this look at the link for the 694 I have above and you'll notice that the stud is in a different location

You win one internet!

I was so preoccupied  chasing broken or jammed up parts that I totally overlooked the obvious.   I set the beat where it should be...more or less..and it started running!   Put on the timegrapher and the little SOB has 260 degrees of amplitude!  That's in it's current crusty condition.   Let's see what it does after a wash and lube. 

[HectorLooi]

I still don't get the part about the cannon pinion. Did it break into two? Did the tube come off the wheel?

If not, just tighten it pop it back on.

[Fissile]

56 minutes ago, HectorLooi said:

I still don't get the part about the cannon pinion. Did it break into two? Did the tube come off the wheel?

If not, just tighten it pop it back on.

The stem is broken off in the movement and the setting lever screw is totally buggered.  I have to order those parts at a minimum, may as well just order a new cannon pinion and be done with it.