Hi All,
I have a 400day clock of unknown maker(It is made in Germany)It needs a new suspension spring. How do I go about determining the correct spring to order? (some guidelines on sizing ect.)
Thanks in advance
P.C.

Peter,

You need to get hold of a copy of the Horolovar 400 day clock repair manual.
They're not expensive and usually available via eBay / amazon and general horological book sellers etc.
Note, there are several editions on the market now, get the latest one if possible!

If you can post some pics of the back plate, someone may have a copy to hand and be able to I.D the clock for you.
My book's in the UK, but I'm not at the moment, so can't help unfortunately.

Best regards

John

i have a copy of the guide as John suggests send a pic of the backplate and I will check it out.

Thanks Clive & John for your replies.
I have posted an image of the backplate.
Any information is much appreciated.
Regards,
P.C.

Yep , all you need is the Holovar guide. I am away from home and for an extended period or I would post the answer from my book.

Moses, thanks for replying to this, you reminded me to check it out.

Peter, the first one I've come up with is a plate style attributed to the 'Associated Merchandising Corp' (Germany)
The diagram is identical to your plate except for some extra text on one side.

Details given are:
(Plate 1012) Page 52.

4 Ball pendulum.
Use .0035" (.089mm) Horolovar Units 19, 20A,21).

Use .0038" (.097mm) Horolovar Unit 27B.

This is listed on page 52 of the 8th edition fifteenth reprint, so there's going to be many updates.
There are more plates to check yet and will update as I find them.

I'm not into 400 day clocks, so no idea what the 'Unit No's' refer to, hopefully someone will chime in and help.

Best regards

John

An update to last nights posting:

Looks like this movement is illustrated on page 117 of my edition, and is identical in every way. All the data for the spring is Almost the same as listed above with the following exceptions:

Dome Clock: Use .0035" (.089mm) Units 19, 20A & 21.

Square Clock: Use .0033" (.084mm) Unit 20B

I've had a quick shuftie through the book and can't see what the 'Unit Numbers' refer to, so hope someone else can help here.

This plate layout is also used by John Wanamaker & the Euramca Trading Corp plus a few others, so probably manufactured by the same foundry to a stock design and sold to a number of different clock making shops.

Best regards

John

If I recall correctly, there is a page with photos that list the different types of suspension setups. They are numbered simply as units.

Thankyou John & Moses,
Your information was very helpful.
Have included an image of the assembled clock for reference. I will purchase the horolovar repair guide shortly. thanks,
P.C.