Reamer or Broach

[Willow]

Hi  i know it might be a stupid question but i am going to buy some broaches for a mantle clock, and this has probably been answered before, i am confused if i should buy cutting broaches or cutting reamers or does it not matter.Thanks Willow

[watchweasol]

The normal tool used is the cutting broach then followed by the smoothing broach, Thos smoothes out any edges and hardens the hole to some extent, being smooth aids the pivot with less friction.

[Willow]

Thanks watchweasol  i will order cutting and smoothing broaches.

[oldhippy]

Get the five sided broaches they are the best. 

[Willow]

Thanks oldhippy i will have a look for them

[Nucejoe]

Five sided broaches.

[Michael1962]

This is something that I have been wondering about as well.

From what I can tell, looking at photos and YouTube videos, the broaches are not fluted like a drill. the cutting faces are straight up and down along the axis of the broach which I presume is pentagonal in shape?

Do the broaches (cutting or smoothing) cut/smooth in both directions then? And then the next question is what size does one purchase or do they come in like a kit of 5? Size of bushes is the next question.

It is only once you start thinking about what lies ahead of you, that the sheer enormity of it all just keeps sinking in.

[oldhippy]

They cut in both directions. You can buy sets or the larger ones individually. The large one don't normally come with handles. Buy the best you can afford, cheap ones will soon lose their cutting edge. Good ones will last a life time. 

You will need a good selection.  

[Michael1962]

Thanks OH. Are there certain brands to look for?

[watchweasol]

Hi Like Old Hippy says they dont come with handles , I use mine with a good pin vice, you may need several vices or find a universal handle with a chuck.

Again buy the best you can afford. There are cutting broaches, the five sided ones and smoothing broaches for polishing and hardening the surface of the new bush.  It does seem daunting at first but once you get started and understand the principals, have read the books and watched the videos it will all drop into place.

[Michael1962]

Ok, so this may be a bit of a long shot, but is anyone able to tell me what size cutting and smoothing broaches/reamers one needs to buy?

I am thinking about the bushing I am looking to have to do. Cutting broaches for the movement plate bush holes, so 1.5mm to 7mm sort of makes sense. For smoothing broaches, we are talking about the pivot holes once the bush has been pushed into the plate, so 0.6mm to 2mm makes sense.

As for bush kits, I am not sure as yet, as looking on the Labanda site here in Australia, they show 2 Bergeon kits with different part numbers, but the same bush dimensions are given in the specs so that is not much help. I would be buying locally as buying overseas and then getting things shipped here as well as customs makes it so close to the same deal, it isn't worth the hassle. Returns becomes even another problem.

I can also get hold of the Bergeon 5488 kit, but that is 450 bushes at $285.00. I don't need that many bushes yet as I am not sure whether I can even get a clock repair business (or anything) off the ground.

Packs of 10 seems like a convenient way but limits what you can do initially? If you then found you need a slightly different bush, another pack of 10 of a different size? I suppose that is one way of getting started and then buying a bush kit later if things get going.

The last thing I want to do is outlay a lot of money which then sits in the garage gathering dust. I fully intend to try and get something going, but the timeframe of that is anyones guess.

And before anyone asks, I will defend my position. I have spent the last 15 months trying to justify myself to my manager at work who was unreasonable in her demands of the position I had. In essence, she has made me second guess everything that I do. A habit that I sincerely trust that I can get out of.

Edited February 20, 2021 by Michael1962

[Graziano]

43 minutes ago, Michael1962 said:

Ok, so this may be a bit of a long shot, but is anyone able to tell me what size cutting and smoothing broaches/reamers one needs to buy?

Hello Michael , I deal with Labanda on a weekly basis , and I often pop in and see Geoff who is the owner . If you want to know any information on what he sells ,he is very helpful .Just give Labanda a call and ask to speak to Geoff ,very nice fellow trust me.

Hope this helps 

Graziano

[Willow]

Hi when i started doing clocks last year i bought 0.60 to 2.00mm smoothing broaches £13. Bergeon 5456 Bush set £48,  1.50 to 7mm cutting broaches £14 though the broaches are not the best you can buy, for me at the time to start with they were good enough and done the job, hopefully more people with clocks can give you advice, take into account i am in the UK and you in Australia companies and prices are going to be different hope that helps good luck

[Willow]

Just as i was typing Graziano replied that sounds helpful if you can speak to that guy

[Michael1962]

And as far as the two kits go that I said have the same sizes shown on the spec sheet, one is in brass, the other is in bronze.

I must have had a 'man look' as my wife calls it.

[oldhippy]

These will do nicely. B-1896-A and B - 1896- B  because you are not going to be re-bushing barrels or Long case clocks. You will need to be able to have some sort of pin vice  or handles for them. 

Clock bushes this type is best if you are just starting. 

https://www.cousinsuk.com/product/english-clock-bushes

[ViktorH]

Bergeon bushes and Bergeon reamers is a good combination. The reamers are not tapered and neither are the Bergeon bushes (except for the very first part of the end that is inserted in the freshly reamed hole).

If using english bushes, I would recommend using broaches instead. Both are tapered. Broach from one side of the plate only to make a great match.

If using broaches to make the hole for the new bush, or if using reamers by hand (and not the Bergeon bushing machine), you will also have to use a cutting broach inside the (originally slightly too small) bush to correct for slight misalignments and then a smoothing broach for burnishing (bothfrom both sides of the plate).

Edited March 10, 2021 by ViktorH

[Michael1962]

So, a little bit more understanding and looking at sizes etc, if you buy a set of Bergeon reamers for use with Bergeon bushes (K series for example) the reamers have a finished parallel (and this is important) diameter which is 0.03mm less than the bush outside diameter. (also parallel) This gives the required friction fit interference for the bushes to be fitted to the plates.

Hand bushing these holes will give you a tapered hole (very slight) that you will then fit a parallel sided bush into. This is not really the best practice. Sure, we are dealing with minute loads etc., but still.

If we use tapered broaches to open a pivot hole for rebushing, the bush should also have tapered sides. Rivetting as per Mr. de Carle's book then makes very good sense.

Has it become the habit (or an accepted practice?) of clock repairers to use tapered broaches with parallel sided bushes, whether they be turned on a lathe or from a bush set (ala Bergeon or KWM)? Is it possible to get broaches which are initially tapered but then finish at the correct diameter to give the correct friction fit relative to the prepared (kit) bushes?

 

Edited June 8, 2021 by Michael1962

[RogerH]

Bushing is still a dark art for me so I will be interested to know the answer and thoughts of the many.

[nickelsilver]

4 hours ago, Michael1962 said:

So, a little bit more understanding and looking at sizes etc, if you buy a set of Bergeon reamers for use with Bergeon bushes (K series for example) the reamers have a finished parallel (and this is important) diameter which is 0.03mm less than the bush outside diameter. (also parallel) This gives the required friction fit interference for the bushes to be fitted to the plates.

Hand bushing these holes will give you a tapered hole (very slight) that you will then fit a parallel sided bush into. This is not really the best practice. Sure, we are dealing with minute loads etc., but still.

If we use tapered broaches to open a pivot hole for rebushing, the bush should also have tapered sides. Rivetting as per Mr. de Carle's book then makes very good sense.

Has it become the habit (or an accepted practice?) of clock repairers to use tapered broaches with parallel sided bushes, whether they be turned on a lathe or from a bush set (ala Bergeon or KWM)? Is it possible to get broaches which are initially tapered but then finish at the correct diameter to give the correct friction fit relative to the prepared (kit) bushes?

 

As Viktor  mentioned above, there are tapered bushings (English style) available that correspond to the tapered broaches- OH linked to them at Cousins. If using cylindrical bushings it would be good to use a reamer that makes a corresponding cylindrical hole. I'm sure fans of either style could argue for hours over which is best, but both certainly work. I was shown by an excellent clockmaker to open the hole for the bushing with a drill, then use brass stock the same size to make the bushing- fit the bushing in the hole, which will obviously be a loose fit, then with the plate on a substantial bench block, smack the bushing with a domed punch and hammer. This forms the oil sink and swages the bushing to the hole. I've tried it and it works just fine.

 

As I make my bushings, most of the time I will simply drill the hole, deburr, turn up the bush, and friction fit it. The drill must be "dubbed", giving it a rake angle of zero or it will grab in the plate. With a ready stock of brass and bronze it just takes a minute or two to make the bushing and they are always just the right length and diameter to suit whichever piece I'm working on.

 

If you want to make your own reamers the Bergeon style is quite simple, turn it to the diameter you want, then taper at perhaps 1 degree for 5 or so diameters, then turn a roughly 30-45 degree angle at the end. File or grind away to exactly the middle, harden and temper to a dark straw color. Even simpler and as supplied by both Favorite and Horia is to turn up your diameter, the grind 5 flats along a taper 5 or so diameters long. It effectively becomes a "normal" broach with a defined final and cylindrical diameter.

Edited June 8, 2021 by nickelsilver

[Michael1962]

Thanks for the reminder about oldhippy's post @nickelsilver. I had forgotten that was posted. Definitely something to look at. It would mean though that I would have to order bushes from Cousins as no-one in Australia stocks this type. Oh to live down here........................

Not having a lathe as yet (or possibly ever to tell the truth - stuck in the 'outlay vs return' conundrum), I may just draw up what I want and then give the drawings to a guy I know that has a machinery shop and get them made for me. It would work for making tools, but totally cost prohibitive for smaller parts like bushes and certainly not for replacement wheels, pinions or arbors. Not sure on how easy it would be to 'hand-broach' for rebushing?

[Michael1962]

I just looked at the Cousins website again and the first bush size that I need requires a 0.5mm inner diameter. Back to the drawing board.

I don't like the idea of trying to hand ream a hole and get it right with the Bergeon or KWM reamers. I can see why a bushing tool would be handy in this instance, except that I could buy an entire small milling machine for less than the cost of a Bergeon bushing tool and I have not been able to find the price of a Keystone hand bushing tool.

[oldhippy]

I think bushing tools are a waste of money. Sometimes they don't hold the plate securely, using Bergeon or K W F ready made bushings the oil sink size is wrong to the size of the pivot and the hole and after fitting they look unsightly. Bushing by hand is far better and making your own bush for the job you will make it more correct. Another thing you never rivot a bush in the plate. Spend the money on a small lathe instead, if you have a carriage I'll say a French one the bushing if done correctly should be invisible, you can't do that with one of those bushing tools. With a lathe you can. I'd like to see someone re bush using reamers a 30 hour bird cage long case clock, for starters you can't buy the sizes you would need so you would have to make your own, beside the cast brass is so hard it will take the cutting edge off in a few rotations.  

[Michael1962]

@oldhippy When you turn your bushes in your lathe, are you putting a slight taper on them to match your broaches? The only reason that I brought up riveting the bush was after reading it in Practical Clock Repairing. I presumed (possibly incorrectly) that the riveting procedure of the new bush would match the existing oil sink angle.

Mind you, in the thickness of a 1 or 2mm movement plate, the slight taper that exists would only be visible under decent magnification.

Edited June 9, 2021 by Michael1962

[oldhippy]

Always a slight taper.