Thread: First clock... A small one

Nice work Russell. Are the joints in the clock face interlocking? You have been at it for a while. I read my plans for a couple of weeks before I started. Only learnt along the way! Keep up the good work!..
Dean.

Looks like a great start and really good to see you enjoying yourself. Keep posting updates.

Dean
Yes they are interlocking. Speaking of interlocking
Went off on a bit of a diversion today. My son sent me this link MAKE | CNC Panel Joinery Notebook
And got me to thinking, so I had a bit of a go and you can see the results. Must remember to clean the parts up before the photo....NO no I want to play NOW
Works really good.
PS The first one was very tight going together but I broke it tiring to disassemble it.
Russell

My son and I are looking to each make Clock 11 as well, but we wil probably be using a scroll saw. I wasn't sure what timber to use. Didn't think ply was going to look any good. It actually doesn't look too bad though, and I think I already have some 6mm ply in the shed. Hmmm.May get started sooner than I thought. May also pick your brains if we run into trouble.

I not the one to ask if you should be making a clock because I am in the honeymoon mode at the moment and why is not every one making a clock. WELL!!!
I will to give you my $0.02, but there are far better people here for ideas.

I think the thing with ply is to use a good one
I am using 5ply marine grade AA finish. It has no voids in the layers and a A grade finish on both sides.


Russell

Originally Posted by petersemple

My son and I are looking to each make Clock 11 as well, but we wil probably be using a scroll saw. I wasn't sure what timber to use. Didn't think ply was going to look any good. It actually doesn't look too bad though, and I think I already have some 6mm ply in the shed. Hmmm.May get started sooner than I thought. May also pick your brains if we run into trouble.

From the reading I've done it seems that Baltic Birch is the way to go. Any good quality marine ply will do though.

Russell, I'm with you in the honeymoon stage. The cussing will come all too soon I fear...

Well my head is still above the water....at the moment
What have I done
A quick clean up of the parts more to do before putting on finish coats.
Pinion are made and in. Made a small tool for this as the pinion are a very tight fit. Use a bit of 6mm brass bar with a 3mm hole in the end and a bit of the mount wood that the chuck held. In photos
Made the 3 mount sets by used a some old curtain rod 30mm round timber. Used metal lathe for this it made them straight forward to make.
Assemble the parts...Just three words = many hours.
Have put it on a test frame and piled some weighs in the bucket and it goes around.

Still to put on the pendulum on but have glued it together today.
Still to make the bob. Got a email from Brian Law after asking him what the weight for the bob is and was told to make it out of hard wood. well that easy I have lots of small bit laying around.
Maybe by the end of the weekend might have it ticking....But I was informed about the hight of the lawn today by SWMBO Maybe the lawn mower might need to be fixed first....fixed in the shed... yes just might need a bit of fixing.....

Russell

Russell that was quick! And yes I know what you mean by the hours involved...many many many. You have come a long way! I also emailled Brian about the pendulum set up. I originally made mine from a huge mild steel rod off cut 150mmX40mm thick! Well that was way too heavy. Mine is now timber as you know and about 500 gramms!
The trick to the set up is to remove the whole setup; bob, rod and its method of attachment to the clock. My plans indicated that I should measure 975mm from the axis of the pendulum ie the bit it swings from. Using a ruler in a vice move the pendulum down the rod until it balances. This will roughly make it swing on time ie 1 swing per second. The fine adjustment nut on the end of the rod will do the rest. You may already know this already; it certainly isn't in the plans. You can also adjust the rod length and pendulum weight to achieve that balance.

keep up the good work! Especially like the pallet adjustment nuts!Ps how does your pendulum attach to the top of the clock ?
Dean.

Dean I do not follow what you mean.
I guessing is you lay the pendulum across the ruler edge at 975mm like a see-saw with the bob on one side and most of the pendulum out the other. Then make it balance by trimming the rod at the bob end.

Russell

I think we are both right but are using slightly different language. In my pic below I am calling the purple bit the pendulum and the other end the pivot end. I think others refer to the pendulum as the bob. The measurement of 1000 is made from the pivot end.Blah blah etc and you know the rest.

This is what Brian sent me.
"The pendulum bob doesn't need to be particularly heavy, the important thing is to adjust the length until the centre of gravity of the pendulum assembly's about 1meter from the pivot. try this laying the whole assembly horizontally across a straight edge and adjust to the point of balance till the straight edge is 1meter from the pivot.
The measurement to the centre of mass to the pivot point is the most important, if it is shorter the clock will run slightly faster and if longer it will be slightly slower.
You can do this by either lengthening the pendulum or by adding weight to the bottom of the pendulum Bob.
For instance you could drill a series of holes at the bottom of the pendulum and insert sections of steel or brass bar to bring the centre of mass further down"
That does that make sense? Hope so....Ps hows the clock going...?
Dean.

Thanks Dean
Had a quick play with some weight (a lot of weight) connected to the drum but I have a lot of friction in getting the hole thing moving. Once it going the weight drops to the floor.
I need to now go through each part and make sure there clean up fully

Dean the pendulum attaches by using a pivot point sitting in a grove on the top mount.

YES I did mow the lawn.

Russell

I too am having trouble with how much weight is needed to get my clock going!; hence the electromagnetic pendulum set up I am going to use. Even though I have bearings throughout and have spent forever aligning holes and shafts I still seem to need alot of weight to make that pendulum swing.

Later

Dean.
Ps congrats on the lawn and now its clock time..........

Dean
I am seeing your problem here and now understand your want to use the electromagnetic pendulum and the weight,
Just now doing some reading on the escapement mechanised and see that the effectiveness is only 50% of my design in a perfect world

Had to change the pendulum pivot point as it just keep rotating it around in the horizontal with each attempted tick. Mount the the end of pendulum on to the rocker shaft. I could then get it to run for a minute or two.

What are the bearing types have you used in your clock?

Russell

Russell I have used roller bearings (the same ones in skate boards) for most of my shafts except two. These have used recycled drive head bearings from hard discs.
These are quiet , cheap and feature a shim which allows the shaft to slide to get that perfect alignment when assembling.
In the pic below the read head on the right gets turned down to the sleeve in the middle! Not much is left. The bearing is on the left and has the corrugated shim. Awesome engineering went into that HD which has now found a new home 20 years after manufacture!

I used them to reduce costs; so far I have spent an amazing $152 on bearings! So i looked for was to reduce costs. I hope to reduce the weight used to drive my clock set up significantlywith my electro pendulum.
Why does your weights drop to the floor? Is it the Paul that is to blame here? I had to re-design my paul as it was woefully inadequate to support the weight. BTW how much weight have you used to get the clock going?
cheers

Dean.
Ps I also had trouble with the pendulum pivot set up so i changed the pin and ring and sleeve bizzo and used bearings to mount it; this set up only allows the pendulum to move in 1 plane only. Hope that makes sense)