How to Assemble a Balance Wheel

The balance wheel is comprised of a number of parts. Below is a guide to how to make the majority of the assembly, excluding the collet and balance spring.

balance1
This is the upper side of the balance wheel. It has an innner bevel, whereas the bottom side is flat.
balance2
The bottom side of the balance wheel, notice that the spokes are flush to the rim of the wheel unlike the upper side.
balance5
The roller. There’s two main parts, the big roller or table roller and the safety roller or little roller. The table roller is on the bottom in this photo, and it has the impulse jewel on it. There’s a groove in the safety roller in line with the jewel which forms part of the safety action of the escapement.
balance3
The balance staff. If you can imagine the staff is in two parts separated by the hub, the part on the left is wher the balance wheel will sit and is the upper side. The part to the right is where the roller will fit on and is the bottom side.
balance4
First things first, you need to find the right sized hole in your staking set. You can do this by putting the balance in a hole until you find the one that is the smallest it will comfortably fit into. Make sure to double check you’ve got the balance wheel side up.
balance6
Now that you have the right hole selected, you will want to use a spike to align the base correctly and then tighten it up.
balance7
Choose you first stake as being one that has a flat top and a hole big enough to fit the balance shoulder in
balance8
The first stake
balance9
You can push the balance wheel onto the balance shoulder by hand and then place it in the staking block. You can then use the stake to push the wheel flat to the balance seat. You only need to use the force of your hand and shouldn’t need to hammer the stake. Be sure that after each push you revolve the stake and the balance as the staking set may have imperfections nd by revolving the stake and the piece you can average them out.
balance10
Visually check the result. The wheel should be completely flat on the balance seat and the riveting shoulder should be showing.
balance11
The next stake needs to have a rounded end, and have a hole large enough to fit the collet shoulder through but not the riveting shoulder.
balance12
After a few hammer strikes you can see the rivet forming as you splay the shoulder out. As before be sure to revolve the piece and the stake after each hit.
balance13
The next stake needs to flatten the riveting shoulder that you’ve just bent down flat forming the complete rivet. It needs a flat top and the same sized hole as the previous stake.
balance15
After a few hammer blowsyou can start to see the rivet flatten out. I’ve not done it quite enough at this point and you can still see quite a step remaining.
balance23
After a bit more bashing the rivet is now flat and the wheel is now joined to the balance staff.
balance16
The next stage is to put the roller onto the bottom half of the balance staff. For this we’re going to be turning the assembly upside down. As we already have the right sized stake for this side we can use the stake like an anvil and rest the balance on. Not all staking blocks have this option, but in this case we can place the stake inside it
balance17
We can treat the new anvil like a normal hole in the staking block, and so you will need to line it up correctly as before using a spike.
balance18
Then place the balance into the stake, making sure that the bottom side is facing upwards
balance19
For the final stake we want one that is curved so it will fit inside the arch of the safety roller. We do not want to damage the roller and will only want to push it into place by hand
balance20
Make sure that the roller is sitting right upto the roller seat. You are only pusing the roller on with the force of you hand, as it is a tight friction fit on the tapered roller shoulder, but not so tight that you can never remove it later
balance21
You will want to align the impulse pin so that it is inbetween two legs of the wheel. This is so that you will be able to see the operation of the impulse jewel during escapement clearly
balance22
The final step is to put the assembly into a poising tool and rotate it to double check to see whether it is straight

2 Comments

  1. David Harris

    Hi Colin,

    Excellent instructions and photos, thank you.

    Do you know a good source on techniques for making the balance wheel itself please?

    Thanks

    David

    1. Colin

      Hi David, many thanks. My best advice would be to give George Daniels’ book watchmaking a look. He goes through the techniques to make every part of a watch in there.

      Colin

Leave a Reply