Your finished timber products can only be as good as the machinery and tooling that process them. By investing in the right knife steel for your particular applications, you benefit from higher productivity and profitability, greater customer satisfaction/repeat purchases, and less downtime.
Choosing the right knife steel depends on a number of factors:
- Type of timber species
- Length of run
- Quality of surface finish required
- Your moulder’s RPM
- Degree of hook angle cutterhead
Knife steel types
D2 – The sprinter
Available in high carbon and high chrome, D2 is good for high-speed softwood planers and moulders. It offers the best value for many moulding producers and planer mills. It’s easy to grind and great for shorter hardwood runs, and also knotty softwoods because it resists nicks. D2 also resists chemical erosion when cutting wet cedar or redwood.
HSS (High-Speed Steel) – The softwood specialist
Specifically used for softwood material, HSS produces excellent finished results. It grinds very cool and can be used on a variety of different timber species.
T1 – The good all-rounder
These knives are HSS, with 18% tungsten, and represent the traditional system in knife and cutting performance. They’re good for both long and short runs on softwoods and hardwoods and offer better resistance to abrasive glue lines.
WR – The long-distance runner
HSS-coated, WR knives are the new generation of cutting knives. They are the entry to Coated Steels – a new revolution in performance. They combine all the best features of HSS, including impact absorption and a supreme cutting edge, with the protection and durability the thin coating brings.
ST1 (Kanefusa) – The best dressed
Compared to regular HSS knives, ST1 has a special coating that gives it an impressive edge life performance. This translates into increased machine run time and reduced grinding costs. ST1 is world-renowned for its cutting results with specific timber species like Western Red Cedar, American Oak and European Oak.
ER+ – The problem solver
The last step before carbide, ER+ knives are an excellent choice for super long production runs and for cutting problem hardwoods. This material is not only coated but the core product is also through hardened to give that density and strength to the problematic running of Hardwoods.
TCT carbide inlay – The tough nut to crack
Hard and robust, TCT knives are the obvious choice for hardwood; particularly on breakdown cutterheads. This design of carbide welded to a HSS backing plate achieves a strong execution when machining robust, dense and cranky timber. When used in combination with solid carbide on the finishing spindles, it will be the ultimate long-life tool and represent great value.
Solid carbide – The unicorn
The hardwood machining holy grail – long run performance and perfect surface quality – it was considered a myth before the invention of solid carbide. Using the ‘pure’ carbide on finishing spindles has made it possible to deliver this ideal combination. The purity of this carbide now allows for the selection of the precise grade and grain of carbide to ideally match the application either in medium density or higher density hardwoods, as well as MDF.
Let’s Talk Knife Steel
Knife Steel can be one of the greatest assets to your operation, but only if it’s done right. Find out below how choosing the right knife steel for your application will not only save you time and money, but create a product that will stun your customers.
Timber Species & Knife Steel Application Chart
Find the right knife steel for your application! Read through our chart and find out what knife steel is the best for each species of timber.
Some of the timber species included are:
- Ash
- Cedar
- Spotted Gum
Your tooling choices are critical
Who would have thought the old Castrol advertisement “Oils ain’t oils” would perfectly encapsulate the evolution of knife steel in 2021? Developments in knife steel have now achieved the ability to deliver a perfect fit to complement all timber species and moulding machines. Like fitting a square peg in a round hole, using the wrong knife steel can be a frustrating and lengthy process that will most likely not achieve the result you’re looking for. Understanding that “Knife steels ain’t knife steels” will absolutely be a game changer for your operation, your production and definitely your surface quality.
Knife Steel FAQ’s
Leon and Steph answer all your most frequently asked knife steel questions including:
- What the difference is between HSS and T1 Knife Steel?
- Why a lot of our larger customers have moved to WR Knife Steel?
- Whether grinding coated steel is a different process to grinding uncoated steel?
3 tips to get more from your knife steel
Over time we can develop behaviours or habits that we pass on to other people or which may have been passed onto us. Whilst most of these are harmless (although not optimal), certain practices should be questioned, changed or even avoided. Here we will look at three ways you can optimise your knife steel to achieved improved results across your operation.
1) Check if your steel is burnt, black or blunt
It’s amazing what sounds and visual signs can tell us. If you hear the moulder ‘murder’ sound, chances are your knife steel is tool blunt! Knife steel can also burn or even turn a black colour due to overuse, damage or through poor grinding practices.
The takeout: Look, listen and stop (if necessary).
2) Look at your LIFE:RUN ratio
Are you re-grinding your knives mid-production run? Consider the disruption to your production and even the loss of revenue when machines or staff are idle. On the contrary you may also be over-capitalising with knife steel exceeding your run requirements. Coated steels or carbide may not be the most cost-effective option if you are doing very small, custom runs. This may also require additional grinding time or even specific wheels.
The takeout: Understand your production objectives to help choose the most optimal knife steel for your operation.
3) Consider a set changeover system/schedule
Many timber processors operate two set shifts – morning and afternoon. What this means is the same knife steel is run all morning, with a changeover at lunch time (to avoid disruption and downtime). In the afternoon the knife steel from that morning is then sharpened ahead of the following morning’s run, and the cycle continues until the steel can no longer be sharpened and requires replacing.
Although your knife steel may have more life in it before sharpening, it probably won’t last the entire shift. Getting on the front foot minimises the work and time required in the grinding room; with less grinding you prolong the actual life of your knife steel. This practice also ensures the consistent quality and value of your finished product, as when the knife performance drops off, your finish deteriorates and will be very noticeable to your clients.
The takeout: Identify a changeover system that works for you to minimise downtime, prolong knife life and ensure consistent quality product.
The results we are achieving from using Accurate’s knife steel are very impressive. We are getting close to three days production before sharpening our solid carbide knife steel at an average of 30,000 linear meters per day.
We have a good combination going here, working together constantly trying to better our process to achieve better product finish and running life from our knife steel.
Richard Keenan Parkside Wondai | QLD
We’ve been dealing with Accurate for a bit over a year and it’s always very easy. All the team is very informative and helpful.
Accurate really knows their business, every time they have suggested we try tweaking something we have seen great results.
This knife steel is the best-balanced knife steel I’ve dealt with. I’ve been timber machining for 17 years now and Accurate provides the best knives I’ve ever used! We’re using less knife steel now and we don’t have to waste time balancing knives when we get them because we know they will be perfect.
Graham Waru Rosvall Sawmill | New Zealand
