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Reamer or Broach


Willow

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12 hours ago, Willow said:
10 hours ago, oldhippy said:

Are you thinking of a watchmakers lathe or one for clocks that will also handle long case clock parts such as the barrels and center wheel?

Hi oldhippy just one for small work like pivot polishing and making bushes etc

 

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I have a unimat 3 with milling attachment and loads of other accessories. The whole lathe is about 17 inches long. They are no longer being made but ebay always have them for sale second hand as well as attachments. Like I already mentioned in a previous post it will handel long case clocks.  They are not cheap and the price is always rising so it is also an investment. The basic lathe are around £300 to £400. There are 3 or 4 on there at the moment with good accessories but far more the £400 but they are extremely good. 

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Below discussion to

13 hours ago, Willow said:

What's the smallest lathe you can use to turn bushes on, don't have much room

Check below discussion. A direct copy of the Unimat 3 is still available as SIEG C0, that's what I have.

 

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24 minutes ago, RogerH said:

Is there a modern day equivalent of the Unimat 3?

Probably the most common similarly sized lathe that is popular with both clockmakers and model makers is the Sherline. They are quite reasonably priced and there are tons of accessories.

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The Unimat SL Micro Lathe was the one before the 3 which is also very good and worth buying many on ebay. Not sure about new equivalent. There are many hobbyist and micro lathes available.   

I would avoid those Chinese ones I have head the finish on them are terrible. Some not even in line.  

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I have searched through ebay Australia and the pickings are very slim. I may have to end up with a Sieg lathe and mill and then go through the work of checking and truing to make them better if required.

I just went to ebay and entered 'mini lathe' and not much gets returned in the search. That's ebay Australia. It would be cost prohibitive even with a secondhand machine to import it personally.

I even had a look at Cowells in the UK, but that was going to cost a fortune.

Edited by Michael1962
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I meant to ask @oldhippy, on the previous page you said that bushes should not be riveted into the plate as Mr. de Carle says in his book.

I would have thought that riveting a tapered bush into the oil sink side of the plate would not be a bad idea considering that the bush is tapered. If the taper on the bush did not match the broach used on the hole, the bush could feasibly come out of the plate. Riveting would avoid this?

Edited by Michael1962
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You see the  broach is tapered so you broach from inside the plate outwards, so from the inside the hole is slightly smaller than the outside, the bush which is also tapered should just fit in side the hole then you hammer it in, by making the bush on a lathe you can have the correct thickness for the plate and the correct sink for the oil. If you have a lathe you can turn down those reddy made bushings. The thing I don't like about those is the colour, they stick out like a sore thumb if you are rebushing an early 1800's bracket clock because the brass is a different colour, so to get it to match I would make one from stock. 

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Is that correct @oldhippy? If you broach from the inside of the plate, the larger diameter will be on the inside of the plate. The smaller on the outside.

When you do your rebushing, did you broach out the plate to remove all of the original oilsink, or when you mention machining an oilsink on your machined bush are you matching the existing oilsink angle?

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The larger diameter will be on the inside of the plate. that is correct. 

You always try to keep as much of the original as possible certainly with what I call proper antique clocks such as French, longcase and bracket clocks, fusse clocks. These so called modern mantel clocks strikes and chimes providing you make a good job of the repairs that is all that is required.  

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So in keeping as much of the original plate as possible, how did you ensure that the oilsink on your machined bush matches the one in the movement plate? Or do you do something like cleaning up the oilsink side after fitting the bush? I presume with a tool like a countersink?

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The way I go about it is by taking measurements, a big factor is the width of the pivot. Countersinks are used for the sinkhole but you don't countersink too much otherwise the pivot has very little of the new bush to run in.   

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42 minutes ago, Michael1962 said:

Was there ever a standard for the angle of a countersink or was/is it whatever the clockmaker has available?

That's why there are so many available. There like stakes when you buy a staking set you find you don't have the right stake for the job.  

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Sigh...................

I am going to have to sell some things quick smart before I touch the subject of wanting to buy a lathe.

Seig, Taig, Optimum, Hafco, Proxxon. There are several other Chinese brands littering ebay as well.

These are all available new in Australia. I have looked for Unimats, Sherlines and other lathes secondhand, but that market is as scarce as anything. Buying overseas and importing myself is pretty cost prohibitive.

Edited by Michael1962
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5 hours ago, Michael1962 said:

There are several other Chinese brands littering ebay as well.

These are mini-lathes, starting 175 x 250mm. They have an advantage over the classic "clockmaker" lathe as they can thread. About the latter check:

 

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Yes there are small ones, but others pop up as well such as Vevor, plain old Variable Speed Mini Lathe, Weiss, JY.

Having bought many Chinese made things, as probably many have, I will struggle to buy a Chinese lathe. I understand that most of all lathes on the internet will have been fabricated in China. Some however have their QA/QC done via the company who owns the brand. Having said that, I saw a Youtube video on a Proxxon (if I remember correctly) that had a wooden drive pulley on the motor. I am puzzled as to how that would occur?

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