How to Repair BOJ Brass Turtle Hotel Bell?
April 25, 2012 at 7:41 pm #12045TurtleBellParticipant
I purchased a BOJ brass turtle hotel bell (PAT Nos 195396 & 30365) that does not ring when the head/tail are depressed. The wind up knob on the outside base seems “overwound” in that it will not wind willingly any further without stubborn clicks. The clockworks inside look fairly gummy. The clockworks also seemingly cannot be removed from the turtle base for easier inspection/cleaning since I do not know how to separate them from the wind up knob on the outside of the base.
Does anyone know of a standard way to inspect the clockworks mechanism for trouble, what to look for, or the sort of repair shop that may be able to do this? This is the first wind up bell I’ve ventured into that is not working, so I do not have experience in what to look for.
Thank you sincerely for any input.
May 4, 2012 at 5:43 pm #16955halanbParticipant
Note: I am not an expert. These are my observations and opinions.
Two options at this point:
(1) Take the turtle bell to a watch repairer and see if you can get him to fool around with it, or
(2) Proceed as below.
Pic 1 shows a common BOJ turtle bell, this one depicting Don Quixote. PAT Nos 19536 & 30366.
Pic 2 shows the four vertical screws that hold the top (shell) in place.
There are also two horizontal screws, one each for the head and tail, but do not remove these.
Pic 3 shows the top removed, the chrome plated bell, and the brass nut that holds it in place.
Pic 4 shows a notch in the rim of the bell, which must be assembled in this position.
With the bell removed, you can begin to see the mechanical assembly and the gear train mechanism. The assembly is steel, and you can see some superficial rust spots. You can see some wear on the gears. This is not a precision pocket watch, but an inexpensive mechanism and it will wear out. The coiled leaf spring is under the top plate, and turns a large single gear (G1) as it unwinds. The other two are double gears, with a small and a large gear on the same shaft. G1 turns the small gear on G2. The large gear on G2 turns the small gear on G3. The large gear on G3 interacts with a ratchet mechanism, which will be discussed below.
Pic 5 focuses on G2, which rotates counterclockwise when viewed from the top. Press down on both the head and the tail, and see if you can manually rotate the large gear on G2 counterclockwise. This may free up the spring if it is overwound. If it does, then you may stop at this point. You might want to clean/lubricate it with something like WD-40 or a graphite based lubricant like Lock-Ease. I would suggest you stay away from oil or anything with water in it.
Pic 6 shows the brass winder for the spring. It has a right-handed thread (screws on clockwise). It should unscrew to the left if given a sharp tap.
Pic 7 shows the winder removed. Note the three brass screws that hold the assembly. They did us a favor by making the mount assymmetric, so there is only one possible way to assemble it.
Pic 8 shows the inside of the brass base. The leaf spring toward the top returns the head and tail to their rest (raised) positions. Note the squarish brass piece running backward from the top of the head. That is the release mechanism to ring the bell.
Pic 9 shows the assembly when removed from the base. You can see the slightly higher G2 on the left, and the slightly lower G3 on the right. The teeth of the large gear on G3 contact the ratchet mechanism that in turn is attached to an L-shaped wire that terminates in the round hammer (clapper). The ratchet rocks back and forth on a central pivot, causing the hammer to strike the bell and then retract.
Pic 10 shows the assembly reattached to the base. When the turtle head is raised, the square piece presses down on the ratchet, holding it so it cannot move and thus freezing the gear assembly. When the head (or tail) is pressed down, the square piece moves upward and allows the gears to turn and the bell to ring.
If you have come this far, you might wish to attempt to clean the assembly further. Again, I would stay away from anything with water (like alcohol), but you might soak it in paint thinner. Then lubricate with WD-40 or Lock-Ease. I would suggest you do not use oil, because you (and I) would always use too much, the excess oil will attract dirt, and the problem begins again.
A better idea might be to take the assembly and winder to a watch repairer, who can clean and lubricate it properly.
May 5, 2012 at 4:32 am #16956TurtleBellParticipant
Thank you so much for your response, and for taking the time to provide such detailed, well-lit photos. Hopefully other owners of dysfunctional BOJ bells will benefit from your effort. Your suggestions for getting the exterior winder loose and hand-winding G2 counterclockwise to free up the jammed spring has resulted in this BOJ bell working perfectly. If bells could think and talk, this one would say thank you. But, since they can’t, it says rrriiinnng!
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