HEAT TREATMENT FAQ’s

HOW SHOULD I PREPARE MY BLADES?

Remove all burrs from edges and from around holes. No sharp edges please and plan to finish grind after the heat treating process.

A hole in the tang is helpful during processing, allowing us to hang the blades vertically. The hole should be at least 3mm in diameter.

The thickness of the cutting edge is important. If it’s too thin there is a very real likelihood of the edge distorting into a wave pattern. This distortion cannot be corrected after it occurs. Non-aggressive and symmetrical grinding will help to reduce induced internal stresses which contribute to distortion. The grit size used when grinding the main blade does not matter but all edges should be taken to at least #150 grit or finer and preferably with the scratches longitudinal rather than transverse. Cutting edges that are thinner than 1mm (40 thou) will markedly increase the likelihood of them warping.

WHERE DO I SEND THE BLADES?

Clarke Knives
Unit 22, Lower Bassett Down Workshops
Wroughton
SN4 9QP

HOW DO I PACKAGE THE BLADES FOR SHIPMENT?

Package your knives securely in the box/package so that they cannot move. They will cut themselves out of the box if they can slide or shift. Wrapping in newspaper or similar material works well. Putting a protective covering (such as cardboard) over the blade tip & edge will help to prevent damage during transport.

Remember you MUST include your Heat Treatment Request Information Sheet with the blades.

WHAT IS THE METHOD FOR RETURN SHIPMENT?

If you are unable to collect your blades they will be returned via the Post Office at their standard rates plus £8 to cover packaging materials and my time & travel to visit the Post Office

Packages over 20kg will be sent via Parcelforce

If you would prefer to arrange collection by courier you’re welcome to do so but you must use a courier who will give notification of when they will collect and the option for me to change that collection time. I’m not always at the Forge (and never on a Monday – that’s part of my weekend!!)

HOW DO I PAY FOR MY ORDER?

An invoice will be mailed to you once your order has been received, inspected and is ready to process. This will include return shipping costs if applicable. Once we receive email notification of your acceptance of the charges your blades will be processed on the next Heat Treatment Day (not longer that 8 days ahead unless you are notified otherwise and possibly sooner by arrangement)

Once payment has been received you will be notified and an estimate of when your package will be delivered to the Post Office. No blades will be shipped (or may be collected) before payment has been received

Methods of payment, in order of preference are:-

  1. BACS transfer to Metro Bank, A/C No. – 29598746, Sort Code – 23-05-80
  2. PayPal to david@clarkeknives.co.uk
  3. Card payment by ringing Graham on 07708-956-036. This service is only available if I’m at the forge
WHAT IS THE MAXIMUM LENGTH OF BLADE ACCEPTED FOR HEAT TREATING?
  • Maximum capacity is 900 mm (36”) in length
  • Axes heads etc must be able to fit inside a 1250 mm dia tube
WHAT HARDNESS CAN I EXPECT ON MY BLADES AND WHAT DOES THE TESTING PROCEDURE ENTAIL?

We will harden to the customer’s requested hardness unless we feel that the request is unrealistic, in which case the customer will be contacted to discuss options any heat treatment commences

If you are unsure what hardness is best for your material please ask for a recommendation on your Heat Treatment Request Information Sheet and we will heat treat to the appropriate hardness based on your material type

We will hardness test where we think it is least likely to show, normally on the tang. If you would like the testing to happen in a particular place, please let us know on your Heat Treatment Request Information Sheet when you send your order. If you would like us not to test your blades please send an extra piece of the same material with your order that we can use as a test piece (and note the request accordingly on your Heat Treatment Request Information Sheet).We are reluctant to return your work without hardness testing as it is our mission to supply quality heat treatment services

WILL MY BLADES WARP?

The short answer is yes, most likely they will distort. Almost all blades warp a little during the hardening cycle because the volume of the metal increases very slightly as the steel hardens.

At Clarke Knives we use our own hybrid system, developed over several years and many hundreds of blades, of a combined oil and press quench. Most blades stay straight (or are straightened) to have no more that 0.1 – 0.3 mm curvature. However, we cannot guarantee this degree of straightness

The customer will be informed of any blades that we feel are warped beyond our expectation, prior to their return

WHAT IS CONSIDERED A BATCH AND WHAT WILL IT COST?

Your shipment will be divided into multiple batches based on thickness and materials that can be processed together. Each batch is then priced separately

If you are sending blades of multiple types of steel in one shipment and would like to confirm if they are compatible to be batched together, please email Graham at  graham@clarkeknives.co.uk or call (07708 956 036) to confirm if the materials are compatible

WHAT IS THE MINIMUM CHARGE FOR?

The minimum charge is to ensure costs are covered for very small order quantities – eg an order for only 1 or 2 knives.

The minimum charge as specified in the Price List applies to each shipment order as received from a client and is only applied if the aggregate charge for all batches in that order is less than said minimum charge. It is not applied to each batch.

WHO CAN I CONTACT FOR PRICING, SHIPPING AND PAYMENT QUESTIONS?

First please go to thePrice List which should answer your queries. If you still have a question then please (preferably) email Graham at  graham@clarkeknives.co.uk otherwise phone 07708 956 036

WHO CAN I CONTACT TO DISCUSS TECHNICAL QUESTIONS REGARDING THE HEAT TREATMENT OF MY BLADES?

Please email Graham at  graham@clarkeknives.co.uk or call (07708 956 036)