Help with hour hand removal/Mainspring question

Posted: Sat Dec 10, 2011 10:14 pm     Post subject: Help with hour hand removal/Mainspring question

I have a Linden mantel clock that was my grandmother's-- It has a bad mainspring and I'm trying to find out what is involved in replacing it.

So far I removed the nut holding the minute hand on-- but the hour hand just will not pull straight off. It has an outer black shaft that seems to extend into the movement-- it has a little play forward/back but just does not want to come off.

Am I missing something obvious?

A newbie question-- but is the mainspring easily user-replaceable? It is a 1051-021 movement from the Cuckoo clock Co. If so-- how do I get one?

I'm trying to get this fixed for my sister before Christmas and this clock has a lot of sentimental value to her.

Posted: Sun Dec 11, 2011 8:03 pm     Post subject:

the hour hand should pull off. To replace the mainspring you need to disassemble the movement, of course you will need the mainspring let down tool/winder (very dangerous to do manually)

Posted: Tue Dec 13, 2011 4:34 pm     Post subject:

Hi Maestro,
The hour hand can usually be removed by turning it as you pull outwards, it is a split tube pushed onto the hour cannon, hold the hour hand toward the middle as you pull, or the hand will bend or break.

The mainspring is another matter - - - there are HUNDREDS of different sizes, and you will need the old one out to measure it up.
The important dimensions are length, thickness of the material, width of the spring.

As Amrad said in his reply, you really need a mainspring winder to do the job properly, it's not worth buying one to do one spring, they are very expensive - - - but without one you risk cutting yourself badly if anything slips.

I used to remove springs by hand, but I wore heavy duty leather welding gloves, and I was very careful. I now use the proper tool for the job, and wonder how I ever used to manage before - - - getting the new spring in was a nightmare !

You may be better removing the barrel with the mainspring in it, and asking a clock repairer to fit a new spring in it for you.

I would certainly be o.k with this if someone came to my workshop wanting this doing - - -

Hope this helps,
Andrew.
http://www.clockmakersandrepairs.co.uk

Posted: Wed Dec 14, 2011 1:00 am     Post subject:

I really appreciate the replies! The job does seem a bit more difficult without the correct tools-- so I'll bring it to an expert. I was quoted $300 to replace the mainspring and do a general cleaning. I'm not sure what the going rate really is-- but seemed a bit steep and is why I was trying to do it myself.

As far as removing the barrel with the mainspring still in it and having someone replace the spring-- does the movement still need to be disassembled to the point where reassembly is a pretty difficult task?

I am very careful and document all processes with photos -- but if you're talking about removing multiple gears and precision placement then I'll definately leave it for the pros.

Thanks again!

Posted: Wed Dec 14, 2011 9:36 am     Post subject: mainspring question

Hi Maestro,

If you examine the movement carefully, you may find that it is possible to remove the mainspring and barrel WITHOUT having to strip the clock down - - - the better quality movements have a plate on the outside of the clock plate with screws in. When you remove this plate a slot is revealed which goes right to the bottom of the plate, and you can slide the barrel out.

Only some clocks have this facility, others involve a complete strip-down.

The other point that needs a mention is MAKE SURE THE SPRING IS "LET DOWN" before trying to do any work on your clock. Mainsprings contain a lot of energy when wound, and the sudden release can cause a lot of damage, to you or the clock.

Once again there is a special tool to do this, but you can use the key with care. Turn the key slightly, holding the pressure use the other hand to move the ratchet pawl out against it's spring, let the key turn SLOWLY as far as is comfortable, let the ratchet pawl back in to hold the spring and change your grip on the key. Start the process again untill there is no power left in the spring, the spring is then "let down" and safe to remove from the movement.

It is not safe to remove the spring from the barrel at this point, as the spring is tightly coiled inside the barrel, this is why you need the mainspring tool to remove it.

Having said all that, $300 does not sound to be excessive for the amount of work involved, if you are unsure about any of this work please let a pro do it, your health ( and fingers ) ! are worth far more than $300 !

Be Safe,
Andrew.

http://www.clockmakersandrepairs.co.uk

Posted: Wed Dec 14, 2011 6:21 pm     Post subject: Re: mainspring question

Regarding spring tension-- I believe the spring is completely broken but do not want to assume it has no tension. When I turn the key there is NO resistance at all-- it just clicks while turning.

Does this typically mean the tension is gone?

Posted: Wed Dec 14, 2011 7:12 pm     Post subject:

Hi Maestro,

It does sound like the tension has gone, but check by lifting the ratchet pawl before removing the barrel.If you can lift it easily and then move the spring barrel centre arbour (the one with the square on) by hand - if you can spin it round either way you are o.k to remove the barrel.

Be aware that even broken the spring is still under tension in the barrel, this is the part where the finger damage occurs for the unwary !

Andrew

http://www.clockmakersandrepairs.co.uk

Posted: Sun Jan 01, 2012 6:39 pm     Post subject:

This is a Hermle movement and therefore as said you can twist and pull off the hour hand by grabbing it as near the center as poss.

when u remove the dial you will see a screw holding a plate with a hole in it holding the ratchett wheel down. as there will be no power on the barrel with the broken spring it is possible to remove the complete barrel by pulling out the center squared winding arbor first. on others it is not poss without removing other bits first.

to be honest, have it serviced by a repairman.