ten10 Projects

Thursday, February 18, 2010

Good Things come in Pairs

Having made the first watch winder, I was eager to improve the aesthetics and the circuitry. The picture on the right shows most of the raw materials that I’ve been using. The housing here was a concept sample I’m building for a customer.

The new unit (pictured below) has a pair of winding rotors that takes care of individual watch’s winding needs. This is a much preferred method of pampering your luxury watches as oppose to two watches on a winding head. In my previous blog post, dated 20th Nov. ‘09, “Two Heads are Better than One” you can see the pros and cons of it.

I’ve since used a new circuit and it now has 2 TPDs (Low and High) but 3 Directional (CW, CCW and Alternating) Settings. I’ve also included a Low Battery Indicator and made a much better-looking housing. It runs on both Mains-power or 4 C-size batteries. I’ve also replaced the Belt-driven assembly with a Direct-drive System on two Portscap motor which obviously has more motor torque and longer life-span; I’m not worried about the belt giving way.

Learning to sew was the greatest challenge here. Having to breathe the glue was a high experience. Constructing the housing was physically and mentally exhausting, even the pressure holding a hack-saw wears out after a certain time. Manually sanding it was tedious and getting blisters is another story altogether. However, it was very satisfying building a unit with my own hands.

Selector Switches and LED indicators are located on the front panel within the housing. The power switch is at the rear of the unit. Main materials used are MDF and PU leather. The viewing window is Plexiglass, 2mm thick.

The battery compartment is below; the unit uses 4 C cell batteries.

Here is the close-up of the controls.

Specifications: -

2 watch winder Winds two watches individually
Winding Mode Controller stops winding when set TPD is achieved, and then sleeps till next
Cycle; built-in 24hrs timer.
Command Board Microprocessor controlled
TPD selection Individual Low 650TPD and High 900TPD
Winding direction Individual selectable CW/CCW/ALTERNATING
Power switch Individual OFF-ON
Drive system Individual Direct-drive with Portescap Gear-motor
LED Indicator Individual Triple-mode Green LED – Power/Winding, Pause and Sleep
Battery Monitor Low-power Battery indicator, Red
Power source 6Vdc; AC Adaptor or 4 C-size Dry cells
Dimensions L245 x W190 x H175mm (approx.)
Materials Black Faux Leather exterior, fine micro-suede interior

Each winding cup can fit a large diameter dial of up to 55mm comfortably. In this case, even large Panerai buckles can be slotted in without squeezing or damaging the winding cup. I wonder if winders in the market currently handle this.

This project serves to test my new circuit, the winding sequence and the tilt angle for my future winders. More importantly, if it keeps my timepiece wound. Well, it’s just the beginning.

Labels: d.i.y. watch winder, homemade watch winder

posted at 1:42 AM by ten10

Friday, November 6, 2009

Your First Homemade Watch Winder

Once you’ve finally assembled the watch winder unit, you’ll truly be excited flicking the power switch for the first time. Well, I was!

As mentioned earlier, I’ve eliminated any possibilities of friction and ensure smooth rotation by using a total of four ball-bearings in this unit. The latter also enables a small DC motor to rotate smoothly. The design is “crude” but it works. I’ve only covered the watch cup with micro-suede because I was too anxious to complete the whole unit.

This unit has 4 modes of operation: -

800TPD - CW
800TPD - CCW
900TPD - CW
900TPD - CCW

At Rest, the circuit draws only about 2mA and depending on the weight of the load, when Rotating it draws as high as 60mA.

The unit functioned as designed and planned for. I will post my updates on a later date.

This was my preliminary sketch of the mechanical construction of the unit. Most of the parts are readily available from scraps, except for the ball-bearings.

I started with making a watch holder, seen here at the top of the picture (left).

This is how it looked like fully

assembled from the front.

Side view of the unit

Rear view of the unit

Only few components were required for this circuit and two such circuits could easily fit into a tiny 5 by 7cm veroboard. This means you could build a Two Watch Winder for yourself.

This video clip shows how it works...

Labels: d.i.y., homemade watch winder

posted at 8:18 PM by ten10

Monday, November 2, 2009

Electronic Parts for Homemade Watch Winder

These are the confirmed parts I’ve used for this project. This circuit is not commercially viable. Please DO NOT use this for other than your own personal project.

Parts List
R1 2K2, Carbon Film Resistor $0.05
R2a 1M0, Carbon Film Resistor $0.06
R2b 1M2, Carbon Film Resistor $0.06
R3 220R, Carbon Film Resistor $0.05

C1 220uF, 16V, Electrolytic Capacitor Free, got it from my junk pile

T1 2N2222, NPN Transistor $0.30
T2 2N3906, PNP Transistor $0.30

LED1 Power Indicator, any color, 3mm Free, robbed from my nephew’s toy

SW1 Rocker or Toggle Switch Free, taken from a junk HP printer
RS1 Slide switch, 2way $1.50

M Small DC Gear-motor, 6V Free, taken when shop staff wasn’t looking,
Just kidding. It’s from my junk pile.PCB Stripboard, Copper $1.20

BH Battery Holder, 4xAA $1.50

Total cost is (SGD)$5.02 with FREE parts were salvaged from my junk pile.

So with the above circuit, I’ll have a two TPD selection. The housing could be built using scrap parts too. It’s a simple way to demonstrate the working principles of a watch winder.

Labels: Circuits, DIY watch winder, homemade watch winder

posted at 8:56 PM by ten10

Monday, October 26, 2009

Want to build a Cheap Watch Winder?

Every where I look, there are many people asking, sourcing, sharing, discussing, swearing, advertising, debating, commenting and lamenting about cheap watch winders in the web. How exactly is cheap? I would think it really depends on how much an individual person is willing to pay for the watch winder. The other thing that would hinder them is the “perceived value” of a watch winder. To really understand “cheap”, just try building one yourself. There will certainly be issues now or later with a poorly designed unit.

To make my point, let’s begin to make a real simple cheapo watch winder!

Basically, a watch winder consist of the following: -

The Housing

Electronic circuits

The motor (rotor)

A watch holder

Power adaptor or batteries (including the battery holder)

Lots of imagination, patience and luck.

The Circuit
I would like to start with the electronics as this is the engine that will drive the motor intermittently to rotate your watches. Only short intervals are required.

All watch winder manufacturer seems to have some sort of “turn-rest” intervals of various timings. There isn’t a standard to follow so you’ll have to create your own.

To have the motor “turn and rest”, use an Astable circuit which will turn ON the motor for a certain “X” time, then turn OFF for a certain “Y” time.

Here’s my suggestion on a basic watch winder circuit which should do the job.

Once I’ve tested the circuit, I should be able to insert values for each part.

The Winding Sequence
There are so many winding sequences for each brand so you must attempt to have your own for this project. To begin, take a look at the type of motor available. Not any type but one which has a gear-head working at a low dc voltage, preferably with a low rpm.

I’ve got a spare 6Vdc motor rotating at 50rpm. This means that I can safely use 4 dry cells. Don’t worry about the high motor RPM as it only requires to make one turn. That’s where your circuit control comes in.

Next, check to see what TPD and which rotational direction your watch requires.

Example, a Rolex winds bi-directionally and require a minimum of 650~800TPD to remain wound. I got this information from a comprehensive database in a website.

Push the TPD a little higher to compensate for “loss turns” if and when your battery drains. Say, between 800 ~ 900TPD should be fine then; or thereabouts.

To determine the On-Off sequence, you have to make some simple calculations.

To save your time, here’s what I think is the best solution.

If I can get the motor to turn 1 rotation every 1.6 minutes, this would equate to about 900 turns per day.

- Divide 1440 minutes (24hrs) by 1.6 = 900TPD

If you want 800TPD, then your motor has to turn 1 rotation every 1.8 minutes.

- Divide 1440 minutes by 1.8 = 800TPD

Referring to the circuit, this means that the ON time (value of R3) has to give just 1 turn for the motor. The OFF time (R2) has to logically be such that the ON and OFF time totals 1.6 minutes. Since I won’t be precise using discrete parts and I can’t control capacitor leakage in my circuit, my timings would be as close as I can get to have this sequence going.

With this “turn-rest” sequence, there’s no way it’ll overstress the winding mechanism inside your watch. I’m confident it’ll keep it wound.

Since my own watch winds bi-directionally, I could have it turn CW today and then CCW tomorrow to give it a healthy “exercise”. What’s more important is that I keep the TPD controlled.

Labels: d.i.y., homemade watch winder

posted at 1:52 PM by ten10