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Swifty
11th March 2008, 02:51 PM
Hi,
Below some pictures of the first clock I made. It's jarrah, with a Hermle movement that keeps reasonable time. I've managed to turn the finial but still need to add the half columns and half turned ends to the door frame.
Does anyone know if the Hermle pendulums are temperature corrected (constant length during heating/cooling)?
Also, what may be the easier way for the half turned columns and ends - should I make full ones and just destroy one half instead of laminating before turning with paper and split after turning?:?
Thanks!

Sprog
11th March 2008, 03:18 PM
Hi,
Below some pictures of the first clock I made.
Also, what may be the easier way for the half turned columns and ends - should I make full ones and just destroy one half instead of laminating before turning with paper and split after turning?:?
Thanks!

Nice looking clock.

Laminate with paper and split after turning. You will then end up with identical columns

ravlord13
11th March 2008, 03:47 PM
G'day Swifty,
Nice looking clock.
Hermle movements are usually very accurate, what movement are you using,
Numbers and type eg( Blackforrest 451/45 )will tell me the movement and pendelum length that is optimal for it.
You should have an adjustable pendelum and to regulate it requires moving the bob up or down the stick.
This should work as long as it is a new movement, if it is older it may need some work.
Post the movement type and numbers and I will try to assist.

Catch ya
Andrew

weisyboy
11th March 2008, 09:16 PM
y not turn a single collum and saw it down teh middle.

nice jod by the way

tazchris
11th March 2008, 10:04 PM
Nice work with your clock.:2tsup:
You should be able to adjust the pendulm speed (swing)by turning the knob at the bottom of the pendulm disk.Anticlockwise to make slower or clockwise to make the time faster.
I would turn a solid column leaving a square top and bottom then rip on a saw or bandsaw.Not really safe joining two halves with paper and turning it.Cheers

Sprog
12th March 2008, 02:37 PM
Split turning columns has been practiced forever and is the easiest method for turning identical half columns.
If you turn the column then saw down the middle they are not true halves and look strange.
Modern glues are so strong the biggest problem is splitting the two halves after turning.
If you are at all worried the joint may split while turning, just wrap some tape around the ends to give you peace of mind.

artme
12th March 2008, 10:07 PM
Nice piece Swifty!! I like it!:2tsup::2tsup::2tsup:

Swifty
14th March 2008, 01:54 PM
Thanks for your comments everyone.

rav & tazchris: The movement and pendulum are fine and there is no trouble with them. In older times, pendulums were made with a combination of metals with differing expansion properties which kept the pendulum at exact length through seasonal temperature variations - I was just wondering whether Hermle pendulums had this property. I will call them and ask.

Sprog thanks for the verification, thought I might have to go that way with the laminate - I was a bit apprehensive but I will give it a go!

ravlord13
14th March 2008, 10:46 PM
G'Day swifty,
Hermle still make multi bar pendelums, but yours is a Stick pendelum the multi bar pendelums have 5 to 9 bars of different metals to compensate for temp change.
Your movement should only need bob adjusment, a half turn at a time then check the gain or loss.
When I build a clock with a mechanical movement it is on the test bench for up to 3 weeks before it is fitted into a clock and then 1 week after before delivery to calibrate time.
cheers Andrew