K&D No.128 Improved Mainspring Winder Set

[Tmuir]

I need to buy or make a mainspring winder to be able to insert the T end mainsprings into my Waltham aircraft clocks.

The inside barrel diameter is around 19mm, so too big for my pocket watch mainspring winders.

Doing a bit of Googling it appears the K&D No128 mainspring winder's largest 'cup' has an outside diameter of around 17mm.

Can anyone confirm this as I think that should be close enough to work, although I would prefer it to be 17.5 to 18mm, but I'm pretty confident 17mm would do.

I just don't want to buy a set if I've got the dimensions wrong.

Or if anyone else has a recommendation for another mainspring winder I'm open to suggestions.

The mainspring height are approx 5.3mm, so the winder needs to be able to fit a mainspring of that size.

Waltham aircraft clocks are size 22s movements

[watchweasol]

Hi Tmuir  have a look at timesavers in the US they market the webster spring winder If you are feeling flush there is the olli baker £300 plus,   I made my own for hole end and loop end is on the site pictures

may spark an Idea.

[nickelsilver]

I know that everyone and every text says to never wind in by hand but every watchmaker has done it out of necessity at some point. If the spring is not too tall in regards to barrel diameter it really can be done without distorting it.

Think of a typical clock barrel, might be 20mm tall and 35mm diameter. Pretty close height to diameter ratio. Taking the spring out requires a winder- as does putting it in. A typical watch barrel might be a depth (spring height) of 1.3mm with a diameter of 10 or 11mm. We take the spring out without a winder without damaging it. It can go back in too, winderless. But you do have to "wind"it. On a t-end spring get your t in the slot, and wrap around 180 degrees, in, wrap 180 degrees, in, untill you're in. As long as the height to diameter ratio isn't to small the risk is low- with a bit of practice. I used to demonstrate this to students and show that the spring remains flat after multiple in-and-outs. They got it too after a few tries.

If course winder is always best but really with t-ends (or worse- seperate t pieces) handwinding is ok if done with care.

[Tmuir]

Hi Watchweasol, I have an Olli Baker mainspring winder but that is for clocks that you wind by putting a key on the mainspring barrel arbor, as is the Webster SPring winder. The aircraft clocks are more like over sized pocket watches, so this type of mainspring winder won't work. Basically I am looking for a pocketwatch mainspring winder that is for larger barrels with an inside diameter of just under 19mm. ALso the mainspring is a T end, so no hole in the outer end of the spring for the hook.

I have NOS alloy mainsprings to fit and I did try to wind one in by hand, but the chip in the paster on the wall on the other side of the room and a ruined rare mainspring tells me I am not going to try that again and risk ruining another spring.

[Neverenoughwatches]

On 11/12/2018 at 6:51 PM, nickelsilver said:

I know that everyone and every text says to never wind in by hand but every watchmaker has done it out of necessity at some point. If the spring is not too tall in regards to barrel diameter it really can be done without distorting it.

Think of a typical clock barrel, might be 20mm tall and 35mm diameter. Pretty close height to diameter ratio. Taking the spring out requires a winder- as does putting it in. A typical watch barrel might be a depth (spring height) of 1.3mm with a diameter of 10 or 11mm. We take the spring out without a winder without damaging it. It can go back in too, winderless. But you do have to "wind"it. On a t-end spring get your t in the slot, and wrap around 180 degrees, in, wrap 180 degrees, in, untill you're in. As long as the height to diameter ratio isn't to small the risk is low- with a bit of practice. I used to demonstrate this to students and show that the spring remains flat after multiple in-and-outs. They got it too after a few tries.

If course winder is always best but really with t-ends (or worse- seperate t pieces) handwinding is ok if done with care.

Hi Nickel. Hand winding is something I nearly always do. Did you mean a winder is always best especially  with t ends or handwinding is OK but really only for t ends ?