ClockClass - The Half-Deadbeat Escapement

This tutorial from the ClockClass DVD selection, "The Half-Deadbeat Escapement," shows a technique for properly adjusting this type of escapement. A poorly adjusted escapement could result in the clock not running so this is a very important adjustment in the restoration of an antique clock.

[@normshafer2243]

Thank you. Seeing the adjustments and the effect they have makes the written word easier to understand.

[@MrsH352]

Thank you so much for a excellent explanation and demonstration .

[@mrphysh]

Thanks. I am working on a clock for a customer. it is identical. I was stumbling around until I saw your video. Okay. I was stumbling around after that also. but: very helpful. Someone before me was messing with it. pretty common in lots of businesses.

[@1dd434]

Thanks for the great video, learning learning.

[@weejohnoo]

Thanks a million, you just really helped me with this video!!!

[@MarkSWilliams27]

Excellent video. Thank you. Adjusting the pallets/verge/crutch, etc. has always been troublesome. I think I better see what is going on now. You took it slow and explained along the way.

[@premierclocks]

Very clear explanation! Thank you, it was helpful

[@jordanrenaud-pq7rx]

Well done. Surprising how small a difference was made by moving the pallet anchor away from the wheel.The move looked huge, but the result was not so drastic, and of course just what was needed. Interesting what happens when the pivot for the anchor moves in an arc when adjusting on these clocks. Truly though, the segment of an arc is very small so of no real consequence.

[@sputnik4216]

Thanks! You make it look easy. I'm going to try again now, especially that last adjustment move. I have problem where it won't keep running .. stops after a few hours ..

[@clockclass5480]

Hi Sputnik- Your stopping issue may not be escapement related. Everything about the movement needs to be considered when troubleshooting power issues. Make sure the movement doesn't have significant wear and is well lubricated. And yes, the escapement does need to be properly adjusted 🙂. But, if your movement is running for several hours before stopping, the problem might not be the escapement.

[@darkgreenambulance]

Noted your adjustment re. catching the back of the escaped tooth. However, I noted also that, as the title states, the closing shot just before the scene faded, showed quite a bit of recoil. Surely this could be eliminated completely? If the anchor surface presented to the escape wheel is radiused to the pivot, there should be no problem.

[@clockclass5480]

Hi Bev- Half-deadbeat escapements do indeed have some recoil and could instead be called "half-recoil" escapements :-). They have a combination of recoil and deadbeat characteristics which make them neither deadbeat nor recoil. American clock companies developed this strap anchor style as an inexpensive deadbeat, not caring that the exit pallet wasn't radial and exhibited some recoil. You are obviously advanced in your escapement knowledge and realize that reshaping the exit pallet would make this escapement a true deadbeat. However, this isn't what the manufacturer had in mind and the effort to eliminate the recoil would exceed the benefit (in my opinion). In other words, a half-deadbeat strap pallet escapement which has recoil isn't problematic. Thanks for your comments!

[@darkgreenambulance]

@@clockclass5480 Many thanks for your reply! Yes, I have seen the term used before and was not doubting your info for one moment! It`s just that I wondered why a half factor would be used. Was it perhaps that a full dead-beat could be a little more noisy - especially on a movement made to a price in various aspects?

[@clockclass5480]

@@darkgreenambulance A deadbeat wouldn't necessarily be noisier but it would take more time to properly shape the pallets. More time means more expense and the clock market has almost always been driven by "faster/cheaper", even at the expense of accuracy. American clock companies mass produced clocks with the half-deadbeat escapement in the early 1910s when society became more dependent on knowing what time it was. America was industrializing (and at war!) and needed to know what time it was in order to catch their train, get to work on time, and know when to quit for the day. The clock market became very competitive and companies which could turn out clocks faster and less expensive than their competition had the best chance of not going bankrupt. So, I don't believe the half-deadbeat strap pallet escapement is anything other than an attempt at deadbeat accuracy on a shoe-string budget.

[@chuckotto7021]

It would be helpful to watch the corrected escapement running for a bit.

[@clockclass5480]

It can be seen here... www.abouttime-clockmaking.com/downloads.shtml or on the full-length DVD. Unfortunately, this 3.5 minute segment can't show everything :-).

[@kwacz]

Would an out of adjustment escapement cause the ticking sound of the clock to be more of a knocking sound?
My clock knocks for a while, then fades to the normal ticking and then back to the knocking.

[@clockclass5480]

Knocking sounds as you describe are more than likely the pendulum hitting something as it swings. The pendulum tries to reach its normal amplitude but then hits the side of the case, or other obstruction, before it reaches its maximum excursion. This dampens the pendulum action, reducing the swing, and the sound goes back to normal. There are several solutions to this issue...
-Make sure the case is level and the clock is in beat. If the clock isn't level, the pendulum will come closer to one side of the case than the other and could strike the side of the case.
-If the pendulum hits both sides, the escapement will need adjusting so there is more exit and entrance drop. This will reduce the amount of swing of the pendulum by reducing the lock.
-See if the obstruction can be moved. I've seen gong standards improperly positioned and interfering with the swing of the pendulum.
Hope that helps!

[@kwacz]

@@clockclass5480 yea, thats what i thought at first, but if i reduce the swing by hand, it doesn't get any better, so i assumed it was escape mechanism because i cant find where the pendulum is hitting anything.

[@clockclass5480]

@@kwacz Ok! This is all part of the troubleshooting process. Look for the easy stuff first 🙂. Since your pendulum isn't hitting anything, it could be your escape wheel has damaged teeth or is out-of-round. This would cause the pallets to lightly catch an escape wheel tooth rather than fully releasing it and cause the knocking sound. This would generally stop the clock. One way to tell if it is the escape wheel is to count the ticks. If you consistently get 7 knocking sounds, for example, followed by 31 normal ticks, it is the EW that's the problem.
Here is an article which discusses escape wheel problems... abouttime-clockmaking.com/pdfs/escape_wheel_problems.pdf

[@paddypup1836]

Could you Bend the anchor slightly to create distance instead of moving the stud ?
Thanks

[@clockclass5480]

Hi Paddy Pup-
Bending the anchor adjusts the entrance drop and moving the stud adjusts the exit drop. So no, you can't really bend the anchor slightly to adjust the exit drop :-).
Great question!

[@paddypup1836]

@@clockclass5480 thanks for reply. This question is actually related to the verge on a cuckoo clock that doesn’t have a stud that’s why I wondered.

[@clockclass5480]

@@paddypup1836 There actually is a stud, sort of, on a cuckoo. It is a finger which is part of the plate and can be bent upwards or downwards. However, repeated bending will cause it to break so try to get it right the first time :-).

[@paddypup1836]

@@clockclass5480 oh thanks.

[@paddypup1836]

@@clockclass5480 so it’s on the brass plate? The anchor on the cuckoo is welded to the pivot bar for use of a better term.

[@bikashbehera3280]

Alarm repair

[@clockclass5480]

Here is a link to an article covering the repair of the alarm on American mantel clocks...
abouttime-clockmaking.com/pdfs/alarms_of_american_mantel_clocks_labounty.pdf