Setting up a grasshopper type clock

[dorsetman]

I recently bought from ebay a battered and rusty grasshopper fusee type clock to restore. This I have now done and it now runs but often stops. The spring is in good order and pretensioned 1.5 revs. Everything is super clean and all the repairs now done. What I want is some kind of procedure to set up the little twin pallets that engage the large scape wheel. I do know that the big twin pendulums should be in line with their opposite number at the rear so its not that. I will get there eventually but a bullet point check list type thing would be nice on setting up the little black pallets, their little springs and their relative positioning to the scape wheel as I feel this is where the error is. When the clock stops its always the left hand pallet appearing not to release from the scape wheel but that might be a red herring. So who out there has got one of these? I look forward to some advice. thanks. Peter

 

[Dave Diel]

I have spent a lot of time with one of these. The basic clock looks virtually identical, although some of the cosmetic features are different.

The (6) ball bearings felt like they had sand in them so I replaced them with Butterbearings and did not oil them per thinking at that time. Since you are in England, you probably won't have any difficulty finding metric bearings. With everything clean and properly lubricated, I spent hours and hours messing around with pallet and pendulum adjustment. Finally, out of desperation, I grabbed the syringe and put some light oil on the ball bearings and it took off like a rocket. With all that motion the clock is very sensitive to friction. The pendulums are adjusted like a compound pendulum and both should be the same height. I would recommend adjusting the springs last and only if absolutely necessary. The one pallet should fully engage the EW just before the other pallet drops off the escape wheel. This should happen when the batons (pendulums) are close to vertical. If your bearings are not perfect, get some new bearings. Then if you can't get it to work, let us know and I can give you a hand.

By the way, it is a crappy timekeeper, but it looks great when it is running.

 

[dorsetman]

I have spent a lot of time with one of these. The basic clock looks virtually identical, although some of the cosmetic features are different.

The (6) ball bearings felt like they had sand in them so I replaced them with Butterbearings and did not oil them per thinking at that time. Since you are in England, you probably won't have any difficulty finding metric bearings. With everything clean and properly lubricated, I spent hours and hours messing around with pallet and pendulum adjustment. Finally, out of desperation, I grabbed the syringe and put some light oil on the ball bearings and it took off like a rocket. With all that motion the clock is very sensitive to friction. The pendulums are adjusted like a compound pendulum and both should be the same height. I would recommend adjusting the springs last and only if absolutely necessary. The one pallet should fully engage the EW just before the other pallet drops off the escape wheel. This should happen when the batons (pendulums) are close to vertical. If your bearings are not perfect, get some new bearings. Then if you can't get it to work, let us know and I can give you a hand.

By the way, it is a crappy timekeeper, but it looks great when it is running.

Thanks dave. I will get back to you. Regards Peter UK

 

[dorsetman]

Thanks dave. I will get back to you. Regards Peter UK

Hi Dave. Clock now running without stopping and hopefully it will go a full week. I had removed the scape wheel and polished the teeth like you wouldn't believe and that seemed to do the trick but I also had adjusted the pallets. I have another question if I may. See picture attached which shows the mechanism (red arrow in the resting position) to push the moon dial around. Once it has pushed up, it will not drop back down again under its own weight. Should it or is their a return spring missing attached to the seemingly useless pin (yellow arrow) and the long black bolt.? I look forward to your reply and thanks. Peter

 

[Dave Diel]

The clock I worked on did not have a moon dial and the photo you attached does not show the overall operation of the moon dial. Could you post another photo from a little bit farther away? BTW, I sure wish everyone would take the quality of photos that you have.

I'm kind of surprised that polishing the EW teeth had that much effect, but you can't argue with results. Yay! I sure hope that yours is a better timekeeper than mine was. It ran fast during the first part of the wind and slow during the second part.

 

[dorsetman]

The clock I worked on did not have a moon dial and the photo you attached does not show the overall operation of the moon dial. Could you post another photo from a little bit farther away? BTW, I sure wish everyone would take the quality of photos that you have.

I'm kind of surprised that polishing the EW teeth had that much effect, but you can't argue with results. Yay! I sure hope that yours is a better timekeeper than mine was. It ran fast during the first part of the wind and slow during the second part.

Hi Dave Thanks for coming back. I found the answer to earlier problem so ok. It was just me being a bit dense. But your right..the timekeeping is atrocious. I have one simple question. When setting up the fusee, how many turns of pre tension to you give the barrel? I have given it 1.5 turns. Was that about right? regards. Peter

 

[Dave Diel]

Hi Dave Thanks for coming back. I found the answer to earlier problem so ok. It was just me being a bit dense. But your right..the timekeeping is atrocious. I have one simple question. When setting up the fusee, how many turns of pre tension to you give the barrel? I have given it 1.5 turns. Was that about right? regards. Peter

That sounds about right.

 

[dorsetman]

That sounds about right.

Thanks Dave. I now suspect the mainspring needs replacing but the barrel looks different to what I am used to. It seems to have two end caps both of which are a very close fit. Is it just a case of thumping the winding arbor to shift the cap on the opposite side or will that damage things?

 

[Dave Diel]

After I oiled the bearings on my clock, I had to change to a lighter spring, .017" if I recall correctly. The balls at the end of the batons kept clanging together with the original .022 spring. Before you look at changing springs, I would recommend putting another turn of preload in the fusee. If it still doesn't want to run, you very likely have power losses in the pivots or the ball bearings.

 

[dorsetman]

After I oiled the bearings on my clock, I had to change to a lighter spring, .017" if I recall correctly. The balls at the end of the batons kept clanging together with the original .022 spring. Before you look at changing springs, I would recommend putting another turn of preload in the fusee. If it still doesn't want to run, you very likely have power losses in the pivots or the ball bearings.

Hi Dave. I increased the preload and after a further pallet adjustment now has clock running. Its an awful time keeper but I will work on that. I did write to Proclock twice asking them for advice on opening up the barrel but no answer. Bit frustrated about that. There must be someone at the NAWCC who has worked on these Proclock barrels and I wish they could find this post and come back. All I want to know is how they would remove the end cap(s). P

has two. See picture. I live in hope. Thanks again. P

 

[Dave Diel]

Smack the tail of the arbor on a hardwood block. I really doubt that the spring is not giving you enough power. As I recall, that's a 1 3/8 X .022 spring, which is BIG. I had to scour the local muffler shops to find a piece of tubing big enough to handle it. If you don't have a stout spring winder, I would not recommend trying it, as this is a spring that could hurt if it got loose. I ended up changing to a .017 spring which is about half the power of the original

 

[dorsetman]

Smack the tail of the arbor on a hardwood block. I really doubt that the spring is not giving you enough power. As I recall, that's a 1 3/8 X .022 spring, which is BIG. I had to scour the local muffler shops to find a piece of tubing big enough to handle it. If you don't have a stout spring winder, I would not recommend trying it, as this is a spring that could hurt if it got loose. I ended up changing to a .017 spring which is about half the power of the original

Thanks again. I did hear yesterday a characteristic clunk of the coils unwinding with a jerk. A noise I am quite familiar with. I heed your warning about the power and will just try introducing some more lubrication and then wind and unwind on my spring winder to work it in.

 

[dorsetman]

Well its now runs for the full seven days but based on 3.5 pretension turns. Im'e ok with that but the timekeeping is very poor and more seriously, the rate is dread-full. The clocks speed can vary from five minutes too fast on day one to an minus number the next. I have logged it over three weeks and there is a vague pattern of slower at the beginning of the week and faster towards the end. But its a very vague pattern. See figures below. So what can I do? Is a weaker spring the answer and why should that be a answer? Help Peter
M - 5 mins
T -13 mins
W + 1 min
T + 5 min
F +4 min
S +1 min
S re wound

M +4 mins
T - 7 mins
W - 1.5 mins
T + 16 mins
F +16 mins
S +5 mins
S re wound

M -6 mins
T + 30 secs
W - 15 secs
T Not measured
F +19 mins
S + 1 min
S re wound

M + 30 secs
T +7 mins

 

[shutterbug]

I'm afraid it is what it is. The Grasshopper impulse design was abandoned many years ago because of it less than stellar performance. They're fun to watch though! Display it as a conversation piece, but set it just before guests arrive

 

[dorsetman]

OK so these Chinese imports are dreadful for timing. There is a company in the UK called Sinclair Harding who make a very similar clock and cost a lot more. I wonder how they get it right. Does anyone know? There is another very well known clock maker called Comitti in London. Again their grass hopper looks almost identical and this time the prices are astronomical. Whats their trick I wonder presuming their clocks work well. Peter

 

[JimmyOz]

Whats their trick I wonder presuming their clocks work well. Peter

There is no trick, you get what you pay for.
I used to work in a clock shop that sold the Comitti and it is extremely well made and engineered, the shop bought 4 of these Chinese copies and after about 6 months gave the money back to the customers and junked the lot, they do not keep time, you have done well to keep it running but forget about it being useful as a time keeper.