CERATIZIT Slots into Heat Sink Production

When IDB Engineering Services was spending up to eight hours producing a single aluminium heat sink and burning through end mills, fighting vibration and watching machine capacity disappear, it turned to CERATIZIT UK & Ireland for a solution. The answer came in the form of the SX slotting cutter, and the results have been transformative.

IDB Engineering Services is the contract machining arm of the IDB Systems Group, based in Llandudno, a manufacturer of specialist electronic equipment, electrostatic instruments, and Hazardous Area Personal Test Meters (HAPTM) – ATEX-rated devices. With outsourced machining costs running at approximately £1,000 for each HAPTM unit, the decision was made to invest in CNC machinery and bring production in-house.

Two Doosan machines were acquired from Mills CNC, a DNM 4500 machining centre and a Lynx 2100LMB turning centre. James Armitage, the Managing Director of IDB Engineering Services, explains: "The machines paid for themselves on the first production run. We had an original order of around 30 to 40 assembly units that consisted of multiple parts, and since then, we have sold well over 100 of those devices. Bringing everything in-house saved us a fortune, and off the back of that we decided to sell the extra capacity – and that is where the foundations of IDB Engineering Services were started."

The CERATIZIT Relationship

The introduction to CERATIZIT UK & Ireland came through Mills CNC, whose local sales engineer recommended James to the cutting tool specialist when the machines were first commissioned in 2017. CERATIZIT UK’s representative, Nigel Walls, visited IDB Engineering Services and evaluated their machining needs. With two new machines on the shop floor, Nigel put together a detailed tooling package that included face mills, AluLine end mills, drills, EG taps, turning inserts for aluminium and stainless steel, parting-off blades, and workholding vices. For a business transitioning from manual to CNC machining for the first time, the guidance proved invaluable.

"We were new to the world of CNC, and we were essentially looking for advice and guidance - CERATIZIT did the bulk of that. Nigel basically created a full tool list based on what we wanted to machine, and that relationship and trust has grown ever since."

As the contract base expanded, so did the tooling inventory. Today, CERATIZIT UK's current area representative, Derrick Jones, visits the site to address technical questions that arise, as the business undertakes increasingly complex work. That responsiveness proved vital when IDB Engineering Services secured a contract that would test its existing approach to its limits.

The Heat Sink Challenge

One prominent customer developing solid-state heating systems for residential and commercial use required batches of aluminium heat sinks across five different designs. With typically 20 heat sinks per order, the regular batch quantity manufactured from 6082 aluminium features fins machined to depths of up to 75mm with a total component height of 83mm. Each fin is separated by a 4mm groove with fin walls just 1.5mm thick.

The original approach used a CERATIZIT 4mm solid carbide end mill on the Doosan machining centre. With significant tool overhang to obtain clearance for the depth of cut, vibration was an immediate and persistent problem. Feed rates and depths of cut had to be kept extremely conservative at around 1 to 1.5mm per pass – just to minimise vibration and maintain an acceptable surface finish.

"With the 4mm diameter end mill, there is a lot of tool hanging out of the collet. It was okay for the first few passes, but the vibration just got to the tool in the end. We were having to take very small cuts to reduce vibration, to make sure the tool survived and to try to maintain a decent finish on the fins," James adds. 

The consequences were severe. Machining time for the smaller early heat sink designs reached almost 8 hours per part. For a batch of 20, that represented close to four weeks of machine time for each batch. Tool consumption was equally problematic with a batch of 10 heat sinks consuming 6 solid carbide end mills.

"It was not just the cost of the tools themselves, but the changeover times too. As the machine was running largely unattended, there could be several hours before you noticed the tool had broken. When a tool broke, it would either get embedded in the material or gouge out a section of the part. Fortunately, it was often salvageable, but there were times when you were scrapping parts." When new, larger heat sink designs arrived with fins up to 75mm deep, it was clear that continuing with the existing method was not an option.

A Step Change in Performance

Looking at the job, CERATIZIT’s Derrick Jones proposed the CERATIZIT SX slotting cutter – an indexable disc milling system that presented a completely different approach. A 250mm diameter SX cutter body was specified, fitted with 4mm wide aluminium grade inserts matched precisely to the required groove width.

Now, the billet is shaped to create its external form and then secured on its side with CERATIZIT vices. It is machined using the SX cutter, which slices through the heat sink with 10mm depths of cut – a 10X increase from the previous method. Commenting on the new process, James says: "It's like a knife through butter. Each pass is 10mm deep, the cycle time is now around 2 hours per heat sink, and the surface finish is much better with the finished part coming straight off the machine. We don’t have to do any post-process hand finishing, which could also prove time-consuming."

With a cycle time reduction of approximately 70% compared to the previous end mill method, the SX slot cutter paid for itself almost immediately. However, it is the tool life data that clearly demonstrates the significant improvement the SX slotting system has achieved. The first set of inserts fitted when the SX cutter was introduced in May 2025 has lasted 10 months, completing more than 50 heat sinks.

"We only changed the inserts for the first time recently, after ten months of use across around 50 heat sinks with 96 grooves each – that is truly remarkable tool life. When you compare that with going through five or six end mills for every batch of 10 parts, the saving in tooling costs is significant. However, the biggest gain is the machine time and capacity that we have got back."

With plans to increase the machine count to meet rising order volumes and ambitions to develop titanium machining, IDB Engineering Services continues to rely on CERATIZIT UK & Ireland for the tooling expertise needed for its next phase of growth. A partnership that began with a single tooling list in 2017 has grown into something much more strategic, and the SX has become its most compelling proof point yet.

CERATIZIT UK & IRELAND Ltd          
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