Review: Timex Sprite – Calibre M75

Timex_Sprite-1Thanks to Christian’s kind offer about opening his WatchGuy blog to selected followers, I couldn’t resist the temptation to hijack the site, and post about a subject close to the heart and usually never forgotten; your first watch ;-).  My first watch was received as a Christmas present in 1974, from my late Grandmother.

I vividly remember opening the wrapping, not know what it was, to discover a Timex wristwatch!  I was pleasantly surprised and really pleased with the gift.

There will be many readers whose first watch would have been a Timex: an entry level timepiece usually with an un-jeweled pin pallet lever movement.  Rather than Rubies, the jewel surfaces used a hard wearing alloy called Armalloy developed during the wartime for long life bearings.  The inexpensive production techniques meant that the development of the M24/M25 movement introduced in the early 1960’s formed the base calibre for the men’s (and boy’s) range of manual rewind wristwatches, including the 21 jewelled versions, M72 & M75.

Timex_Sprite-4_M25
M24/M25 movement.

 

Timex_Sprite-5_M72M72/M75 movement

I never found out the exact purchase price, but believe it was or £4.99, which is about £38.00 or $61.00 in today’s terms. Not a bad price.  The watch case and case back are stamped France, and the dial & hands were manufactured at Felton, England.  The movement was entirely manufactured at Dundee, Scotland, where final assembly also took place in 1974.  The watch was from the Sprite series, with a 30mm diameter chromed case and stainless steel back.  The white dial is of a design not often seen.

Timex_Sprite-2Plastic retaining ring

It is unusual in that the 02574 code on the watch face indicates that it should have an M25 un-jewelled pin pallet movement fitted. But this watch left the Dundee Manufacture with Timex top-of-the-range M75 21 Jewel movement!  As the two movements are dimensionally identical, either would have fitted the chromed case with the plastic spacer ring.  This may have been accidental, but the nice girl at her assembly desk, could have fitted it deliberately.  Production of the M75 was phased out in the early 1970’s so perhaps the movements were being offloaded.

 

1_Timex c

Production line, Dundee, early 1970’s

Timex_Sprite-3M75 movement in my watch

The M75 is the same movement as the 21 Jewel M72, with M25 calendar module fitted.  The dimensions are 11-¼ ligne by 9-¼ ligne.  The frequency is 18,000 VPH, and the power reserve 42 hours.  Timex saw their 21 Jewel movements as being somewhat superior to Swiss lever escapement movements, and were fitted with ruby pallet pins permanently fixed to the escapement.  The movement service manual stated the following: The Model 75 is readily distinguished from other Timex movements by the number of jewels and the small, gracefully decorated movement plate.  Whereas most watches utilize bridges, Timex has constructed the Model 75 movement with full plates to take advantage of the accuracy inherent in this type of design. This accuracy insures complete interchangeability of the escapement and gear train without the need for selective fitting and adjustments which complicate the repair of most watches.

Another important feature of the Timex Model 75 is in the escapement. Timex has developed a jeweled lever escapement which functions exactly as the conventional escapements, but eliminates the danger of loose pallet stones.  In conventional jeweled club-tooth lever escapements, the pallet stones lie horizontal to the plane of the lever and ore normally shellacked in place.  This type of construction leads to frequent loosening of the stones during cleaning, thus requiring readjustment. The Timex design, however, uses pallet stones vertical to the pallet lever which are driven permanently in place.  Since they are not fixed with shellack or other adhesives they will not loosen during cleaning and will not require adjustment, thus retaining full accuracy in the escapement.”

What can one say!

Timex_Sprite-6_M72

Detail of ruby pins & escapement.

It is still ticking away and keeps quite reasonable time. I last had it serviced in 2006, where the local watch repairer I used carelessly mauled the second hand on removal from the face!  Paint was scraped off, as can be seen in the photograph.  I note from this damage that the hands appear to be made out of copper.  The crystal was also replaced at the same time, but the photograph shows flecks of dust and even what appears to be a hair/textile fibre on the watch face.

Timex_Sprite-7

Damage to second hand.

It was my everyday watch for 7 years after 1974, although the original black plastic watchstrap didn’t survive.  I only wish I had kept the original box it came in, although it was a plastic blister pack, through which the watch was visible.

6 thoughts on “Review: Timex Sprite – Calibre M75

  1. Thank you for posting this. I enjoyed that indeed. I admire those that can service such small pieces of workings.
    It got me thinking about provenance and the satifaction in owning such a piece of history of such personal value.
    I am now digging out a few watches I thought I did not like but having took an interest in watches again realise that the value of provenance is sometimes equal to owning one of high monetary value.

    Thank you

  2. Many thanks for that Scott – very interesting reading.

    I had always assumed these Timex movement could not be serviced as they appear to be riveted together? Looks like you can get to both sides of the various stems on the non-jewelled versions so maybe you can lubricate them that way…

    • Hi Cirrus,

      The Timex service manuals for the M25, M72 & M75 movements certainly show that these movements can be dismantled.

      The M72 manual states this; “All cap jewels of the Timex Model 72 are removable. To clean the Timex Model 72 it is necessary to remove only the sweep second hand, dial, ratchet wheel, wind and set mechanism, minute wheel, cap jewels and balance. The illustrations on pages 72 .3 to 72.6 show proper procedures. Timex
      has found through long and careful research that the best method of cleaning is with only the above mentioned parts removed. The cleaning fluid, while removing any contamination from the movement will also remove oil from the pivots and holes.
      If further dismantling is required, removal of the movement plate will expose the gear train and associated parts. Reassembly should start with the dial plate, exercising normal care to insure proper positioning of pivots in their respective holes. The exploded view of the movement on page 72.2 will guide reassembly.”

      Perhaps accurately positioning the pivots between the plates is a pig to do! Christian will just have to service my Timex at a future date for a full report & critique. 😉

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