Watch servicing & repairs

We are specialists in servicing and repair of all vintage CWC watches, Seiko Gen 1 and 2, other Seiko 7A28/38 variants, Smiths, Hamilton, Benrus, Marathon/Adanac and Precista military watches. We also have experience with other brands including Omega and Lemania. See our Projects page for some examples.

We have a 10+ years track record of working for military watch owners, including some of the best known collectors in the UK, helping to return their watches to full working condition and ensuring that they will perform well for many years to come. See our Testimonials page for comments from previous customers.

As we also do all the servicing and repairs of our own stock, we only have limited capacity in our workshop to carry out servicing and repairs for customers. We therefore maintain a waiting list for repair jobs. We will only accept jobs that we are confident can be turned around within a reasonable timeframe and completed to a high standard (e.g. good parts availability), so requests are reviewed before they are accepted onto the waiting list.

As a rule we will not accept pre-war watches for servicing/repair or non-UK repair jobs.

To enquire about a service/repair request please complete and submit our Service/Repair Enquiry form

Watch servicing specification

All watches are serviced to the manufacturers specification (where available) and using best bench practices, quality parts and lubricants.

The normal process is to inspect the watch and check its operation soon after arrival, and to diagnose any reported problems, as well as any other issues. An initial report is made to the owner before any parts are ordered or any further work is undertaken.

Once works are agreed the case parts and movement are stripped. The case parts are ultrasonically cleaned, the movement parts are ultrasonically and mechanically cleaned in waterless solutions and hot air dried. The movement is then rebuilt and lubricated. For mechanical watches we generally use a new mainspring where available, to ensure the best performance for the watch. Once the movement is rebuilt it is tested to ensure complications such as chronograph or calendar works are operating correctly. The movement is then regulated for accuracy. Quartz movements are regulated for accuracy where the circuit board supports this adjustment.

Gaskets are replaced and greased and the case parts are reassembled (e.g. pushers and rotating bezel refitted), the dial and hands are refitted and the movement re-cased. Before the completed watch is returned to the customer, it is re-regulated and bench tested.

Servicing and repair costs

We have a tariff for typical servicing and common repair jobs for different watch types/movements. Once we have your repair request we can provide an estimate base on our repair tariff. Parts and return postage are in addition to the base cost for servicing. All estimates are subject to inspection of the watch itself and to any issues that come to light during inspection or servicing.

Sending your watch to us

If your watch is on our waiting list, we will contact you when we have workshop capacity and will ask you to send the watch to us. Watches are sent to us at the owners’ risk and we are not liable for any loss or damage while watches are in transit to us. Watches should be sent using a tracked service (Royal Mail Special Delivery is recommended) and you should provide us with the tracking number. We will confirm when the watch is received. We will carry out an initial inspection within a few days and will report back to you before any further work is undertaken.

Packing guidelines

• Do not pack the watch in any case/box/container which you want returned

• Remove any NATO type straps before sending the watch to us

• Ensure that the inner packaging is waterproof. We recommend that the watch is sealed into a plastic bag before packaging

• Use plenty of padding/bubble wrap but DO NOT wrap it with adhesive tape – use the minimum amount of adhesive tape to hold the padding/bubble wrap in place

• Once the watch is suitably protected, pack in a box or jiffy bag. Make sure that the watch is tightly packed into the outer container to ensure minimum movement during transit.

• Do not pack watches loose inside padded envelopes, especially if there is more than one watch in the package.

Watch repair guarantee

All watch repairs carry a 6 months mechanical, non-waterproof guarantee. This is covered under the same terms as our 6 months guarantee for watch sales.

'Jos at Sumac Watches is 100% reliable, communicates and has completed each job I’ve asked of him, flawlessly. He can be trusted without a shadow of a doubt. Jos has been working on my watches for over 12 months ranging from a small niggly problem to full watch servicing and all the way to fixing a watch from a total loss into what is now one my favourite watches and well known in the CWC community. Jos is a pleasure to deal with and I would recommend his work to anyone.'

Justin, Hatfield