To bush or not to bush?

[Rixy]

I have taken apart an old 1930s Bentima Westminster chimes clock and it looks like it was rebushed in the past but some are a bit iffy (not quite dead-on), some are developing oval holes and one has clearly been reshaped by being hit a few times with a punch. I have attached a few photos, sorry they are not that clear - it's the best my phone can do. I think the plates probably need rebushing but I have yet to try doing this.

Can it be done by amateurs? What equipment should I get? I have seen people cut their own bushings on a lathe (I do not have a lathe) but I see that pre-cut ones are also available from Cousins.

As ever, all advice gratefully received. 

[Jon]

The thing is, you never know if the last clockmaker bushed these properly, or if they are in the correct position.

Let's assume they have been done properly and have worn oval, then it would be a good idea to press them out and new ones pressed back in place.

If the position of the bush is questionable then you have a bit of a headache on your hands, as I assume you don't have a clock reaming and bushing tool.

If you don't have the correct tool to sort this out, I wouldn't attempt it, as it is only going to go pear-shaped on you very quickly if you haven't done this before with the correct tools.

 

[Rixy]

Thanks Jon. I might put it to one side until I get more experience and have time to start an horology course.

[watchweasol]

Hi as Jon said are the bushings correct ?  To find out you will need to dismantle the clock and check the intermeshing between the two interrelated wheels for tight spots or bad mesh bearing in mind some are already worn. If they all check out you can press out the bushes and fit new ones and broach to fit the pivots.  Bushing can be done quite easily by hand, you don’t need £1,500 pounds worth of Bushing machine. Always cut the hole undersize and broach to fit the bush ( friction fit) then broach the bush  to the pivot. When the wheel is inserted to the bush there should be no more than 5% side motion from vertical. Always fit a bush from the inside of the plate, I use a bench drill with a punch inserted to press the bush home . Once fitted and cleaned up cut the oil sink carefully and the bush should be invisible.  It isn’t rocket science it just requires application and care.

[Jon]

12 minutes ago, watchweasol said:

Hi as Jon said are the bushings correct ?  To find out you will need to dismantle the clock and check the intermeshing between the two interrelated wheels for tight spots or bad mesh bearing in mind some are already worn. If they all check out you can press out the bushes and fit new ones and broach to fit the pivots.  Bushing can be done quite easily by hand, you don’t need £1,500 pounds worth of Bushing machine. Always cut the hole undersize and broach to fit the bush ( friction fit) then broach the bush  to the pivot. When the wheel is inserted to the bush there should be no more than 5% side motion from vertical. Always fit a bush from the inside of the plate, I use a bench drill with a punch inserted to press the bush home . Once fitted and cleaned up cut the oil sink carefully and the bush should be invisible.  It isn’t rocket science it just requires application and care.

I think you meant 5 degrees from vertical, not 5%. Good advice was given though!

31 minutes ago, Rixy said:

Thanks Jon. I might put it to one side until I get more experience and have time to start an horology course.

If you live near South London, I run small classes of six for watchmaking courses. Check out my website: https://www.jonthewatch.co.uk/

If you are interested in clockmaking courses, check out EFHC in Essex where I used to teach until July this year: https://efhc.org.uk/wordpress/

Edited September 7, 2023 by Jon

[Rixy]

Thanks Jon. I am interested in clockmaking (are you watchmaking only?) and was considering the place in Essex. Am quite busy at work at the moment but will have more time for this in about 12 months.

Hi Watchweasol, I have a broken 1960s Smiths movement that I have salvaged bits from. I might have a practice rebushing that - it won't matter if I mess up!

To press out a bushing, what do uou use to press out the old ones?

[Jon]

11 minutes ago, Rixy said:

Thanks Jon. I am interested in clockmaking (are you watchmaking only?) and was considering the place in Essex. Am quite busy at work at the moment but will have more time for this in about 12 months.

Hi Watchweasol, I have a broken 1960s Smiths movement that I have salvaged bits from. I might have a practice rebushing that - it won't matter if I mess up!

To press out a bushing, what do uou use to press out the old ones?

I'm a watchmaker, so Essex is the way forward.

You would use a clock bushing/reaming/pressing tool. You could do it with a watchmaker staking set, or even with small hand punches, although when pressing them back in you have to get the correct end-shake. You could use a watchmakers jewelling tool, as you have a micrometer setting to get the depth of the bush perfect.

Edited September 7, 2023 by Jon

[watchweasol]

Hi. To press out the old bushes I would use the same method as putting them in. As I don’t own a Bergeron tool I would use a small diameter punch in the drill press over a holed plate or a big nut. The watch makers staking set, of which I have two I feel are a little delicate for that type of work and may get damaged.  There are clockmakers sets which are a bit more robust. As to setting end shake the bush needs to be flush with the inside of the plate only and is not as critical as in watches.

If you have an old movement all the better to practise with. Hand broaching and drilling out worn holes Just takes care, there is plenty of guidance notes etc on the net to look at.

[oldhippy]

Tap out all those bushings. As you are just starting out buy a box of Bergeon Number 4166 this will cover most of what you will need. A set of clock bushing Broaches get the best you can afford if you can afford get  Bergeon they will always keep there cutting edge. German ones are also very good. A good set will last a life time. There is no reason why you shouldn't be able to handle this. There are some videos on this on youtube. 

[Rixy]

Thanks everyone. Had a look on Cousin's site. A box of Bergeon 4166 is around £77, is that about right? Have seen a set of Bergeon broaches too that I can get. Need to get a drill press and some punches too so might wait until pay day!

[oldhippy]

You don't need a drill press. That is a waste of money. you shouldn't use power tools on clocks. 

That is about the price. 

Edited September 8, 2023 by oldhippy

[watchweasol]

I think I said I use a bench drill as a press. It’s a tool which if you have is usefull for the job, it is an option only if you have one to hand, just as you don’t need Bergeron broaches or Bergeron tools to do the job there are many watch tool makers do Broaches. I got mine from Melvyn Passmore when he was in business and they are good as were his other tools .

[Neverenoughwatches]

21 minutes ago, watchweasol said:

I think I said I use a bench drill as a press. It’s a tool which if you have is usefull for the job, it is an option only if you have one to hand, just as you don’t need Bergeron broaches or Bergeron tools to do the job there are many watch tool makers do Broaches. I got mine from Melvyn Passmore when he was in business and they are good as were his other tools .

That sounds like a great idea the drill press without plugging it in, like a large jewelling tool with the addition of a revolving sprindle. I have just the thing.

14 hours ago, Rixy said:

Thanks everyone. Had a look on Cousin's site. A box of Bergeon 4166 is around £77, is that about right? Have seen a set of Bergeon broaches too that I can get. Need to get a drill press and some punches too so might wait until pay day!

Any car boots near you ? I often see drill presses for around 20 -30 quid, they dont even need to work electrically if you are just using it as a press, they usually have a depth stop. 

[Rixy]

31 minutes ago, Neverenoughwatches said:

That sounds like a great idea the drill press without plugging it in, like a large jewelling tool with the addition of a revolving sprindle. I have just the thing.

Any car boots near you ? I often see drill presses for around 20 -30 quid, they dont even need to work electrically if you are just using it as a press, they usually have a depth stop. 

Good idea. I hadn't thought of checking them out. I'll see what's coming up. Thanks.

[Neverenoughwatches]

9 minutes ago, Rixy said:

Good idea. I hadn't thought of checking them out. I'll see what's coming up. Thanks.

 

9 minutes ago, Rixy said:

Good idea. I hadn't thought of checking them out. I'll see what's coming up. Thanks.

This one was a fiver inc. a half decent electric power drill. It won't have quite the same application as the purpose made pillar drill as there is no stop , but it gives you an idea what you can pick up for very little. I talk to the regular sellers when i go and they all say how hard it is to sell at the moment, its definitely a carboot buyers market. But folk having old parent's garage clearouts nearly give stuff away, just to dispose of stuff without actually disposing of it. If you pick something up its always nice and interesting how well you've done. 

[oldhippy]

Please tell me what you intend to use a drill and its press for. 

[Neverenoughwatches]

1 hour ago, oldhippy said:

Please tell me what you intend to use a drill and its press for. 

Hiya OH. I thought the idea was to use one to press in a clock bushing . I assumed like a large scale friction press. It sounds like you're not up on the idea ?

[JohnR725]

Out of curiosity when replacing a bushing in the clock because it's worn out what you going to do about the pivots? In other words if something like a hole in a plate is worn do you ever see Pivots in need of refinishing?

 

[oldhippy]

I have always used watch staking tools, with a small hammer, the bush should be a third way in the hole so it doesn't take much to hammer home. Pivots should be looked at for signs of wear and roughness, tidy up by removing marks this is done by using needle files, a small Arkansas stone, emery sticks then finally burnish them all.   

[HectorLooi]

I have been using my watch staking tool to press in and set the bushings. But recently I had to rebush a centre hole and the staking set just can't reach the hole.

Is the a bigger staking set meant for clocks?

[oldhippy]

This is where a block comes in handy. Just google watch makers blocks. I had a steel block with out holes. Don't buy brass as you know brass is soft and it will soon dent. 

[HectorLooi]

I have several staking blocks. I used the plain one without holes for the centre hole bush I mentioned above.

I also have this dental laboratory tool called an undercut surveyor. I thought of modifying it to hold staking punches. I could also make a bushing tool out of it.