My Wooden geared clock

[NCArcher]

Bugger. You'll have to re-read the thread to see how you did it.

[Walesey]

Dean, That is heartbreaking! I wonder if that is why the originally moved from using wood to using brass for clock gears?

I certainly hope you can mend it

regards
Walesey

[1964deano]

That one piece had the grain running in the wrong direction...
Dean.

[1964deano]

Walesey, the gear cannot be mended...I will have to re-do.Brass would be more stable that timber. Not as beautiful but..
I have pulled out the gear to check which direction the grain was running in that failed piece also what direction the grain was running the adjacent pieces. It is the first gear that has failed. The first picture shows the whole gear. The second picture shows the failed piece. The third pic shows the piece that has moved the least. It seems that the grain in the best piece is running at righ angles to each other. Is this the way to do ? Any help on the best way to run the grain is needed here!!! This time I will be freezing the pieces for a week then thawing then re-freezing. See how that goes.


Dean

[dj_pnevans]

How about making two with half the thickness and lay in metal the glue together.
David

[1964deano]

How about making two with half the thickness and lay in metal the glue together.
David

Hi David,
I think that sheet metal wont provide any lateral strength to the gear. What metal and glue did you have in in mind?

Dean.

[1964deano]

Just started the layout of the gear pieces in relation to the grain direction. I have alternated cup up / cup down and have just started work on what direction each piece should go. Then into the fridge for a couple of weeks.


more later.

Dean.

[1964deano]

My seven pieces are now cut to rough size and stacked vertical in the freezer, and will spend 3-4 weeks at -15. They will then be re-thawed for the same amount of time.
On the weekend I discovered Bamboo plywood from Leto http://www.letobamboo.com/index.html at a conferance I was at over the weekend in Melbourne. So impressed was I with the 20mm plywood that I will try a full gear while my wood freezes.
I will post some pics when I get hold of some bamboo to practice on.
A question for the brains trust : "What do you think about using Bamboo to make clock gears from"?
cheers Dean.

[nine fingers]

That one piece had the grain running in the wrong direction...
Dean.

With reference to your quote , grain running in the wrong direction. Here's a photo of the gears I cut for my clock in 2006, the timber used was Satin Box
from my area Otway ranges near Geelong. The gears were cut from a single piece of timber, ALL the grain running in one direction. I have not had any splits or movement of the wheel shape in in 9 years. The clock runs for approx 70 hours when the twin weighs are fully wound up.
It echo's down the passage so its not wound up too often. A couple of photos of the gears . John.
( Its been now put into grandfather type case to silence it a bit}

[1964deano]

so Satin Box must be close grained and slow growing?

Dean.

[1964deano]

While waiting to make the gears, I have started designing and making the weight boxes. Thanks to Chris Parks for donating the lead!. I have decided to use 150x50x3mm RHS to house the lead. It is cheap and reduced the amount of lead i need to the exact amount that Chris donated!
I have re-mounted the mini weight pulleys so that the weight boxes are nicely balanced. I have calculated the volume of lead that i need and that its height inside the RHS to be 95mm. This has determined the overall height to be 130mm with a little room for extra lead if required.Pic 1&2.

The next task will be to make the mold and cast the lead. An awful job on all accounts...

Dean.

[NCArcher]

What is the mold for? I thought you would be pouring the lead straight into the weights.
Around 8 kgs per weight? 6.8 kg of lead and about 1 kg for the steel?

[1964deano]

I want to be able to remove the lead if the need arises...yes 7 kgs of lead 1 kg of steel

Dean.

[1964deano]

Hi everyone,
I initially weighed all the lead I had on hand and divided it into two equal piles.
Today I made my weight moulds and my first clock weight. I weighed out 6kg of lead and proceeded to melt that. I decided rather than melt all the 7kg in one pour, I dropped 1 kg to accommodate the extra pieces to the weight boxes that have not been weighted as yet. Its alot easier to add lead than it is to try and remove some.

The mould I made was constructed from concrete form ply which stood up to the heat just fine and with no leaks! I screwed some steel strap to make some channels so that the weight could be inserted from the top past the bolts that were welded on the inside.
I made the mould so that the lead could be removed....just in case. After cooling I had lost 300gms due to impurities which I had not factored in. I will repeat this process once it has stopped raining.


cheers

Dean.

[1964deano]

Today I cut my weight box to length and welded a brace on the base. To this i have fitted a 5mm piece of alley plate which will be trimmed flush tomorrow. Not much progress

At present the empty box weights 1.8kg. So only minor additions of lead will need to be made to achieve the 8kg needed.

Dean.