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Send a photo of the cut, the aggregate, the blade. We will tell you what we think before we tell you what we sell.
Open WhatsAppCoolman · Diamond blades for concrete, granite and tile · Selangor, since 2007
The Right Blade for Concrete, Granite and Tile.
Coolman makes diamond blades, core bits and cutting systems for concrete, granite and tile. We have built them in Selangor since 2007. Alan, our founder, has cut for a living since 1998, so every blade is matched to the rock, the rebar and the deadline a Malaysian site throws at it.
What contractors live with
Four things keep the boss up at night. We've watched all four on site.
A delay you cannot explain to the developer
The blade is slow. The schedule delays. The customer is already calling. We have watched this happen more times than we wish.
Equipment that fails at 11pm on a road closure
When the cut has to be done tonight and the blade gives out at the wrong moment, the cost isn't the blade. It's the closure, the police, the developer phoning at 6am.
Inconsistency between blades that should be identical
One blade cuts. The next one of the same SKU lasts half as long. The crew loses faith. The supplier loses the account.
Being left alone with a cut nobody else has seen
A new aggregate. An unusual depth. A spec the supplier has never tested. The crew gets it. The supplier ducks the call.
Three myths
Three things the cutting trade keeps getting wrong.
The cheap blade costs more by the end of the job. The dealer who's never been on site can't tell you why your blade glazed. And 'Made in Japan' doesn't mean it was made for cutting Malaysian concrete.
Read the folioThe Brotherhood System
How we work with the people who buy from us.
Dealers and contractors who work with Coolman get direct access to engineering, not a points system. If you carry our blades, we treat you like a partner, not a customer number.
See the five principles不要只卖产品，解决问题
Engineering
Malaysian aggregate is not European aggregate. It breaks blades built for Europe.
The diamond segment is a wear part. It is engineered to erode at a specific rate so that fresh diamond is continuously exposed to the cut. The matrix — the cobalt-bronze alloy holding the diamond — must wear at the same rate as the work the blade is doing. When the matrix is too hard, the diamond glazes over and the blade stops cutting. When it is too soft, the diamond falls out before it has done its work.
The matrix that works in Europe is calibrated for European aggregate: limestone-based, low-silica, predictable mineralogy. Malaysian aggregate is the opposite. KL crushed granite runs above 60% silica content. The fines are sharper, the inclusion of quartz is higher, and the compressive strength does not predict the cutting behaviour the way a European spec sheet implies it should.
Coolman's response is a cobalt sandwich segment. Three matrix layers of graded hardness, laser-welded to a tensioned high-carbon steel core. The outer layers carry the cutting load. The middle layer is softer cobalt — it releases the diamond before the matrix glazes. The result is a segment that wears at the rate the work demands, not the rate the bond was originally calibrated for.
The argument is unremarkable inside a tool manufacturer. It is rare in this market because most blades sold in Malaysia are imported finished and not re-formulated for what the ground here actually does.
62%
Silica content. Malaysian crushed granite, KL aggregate sample, Q2 2024.
3.1×
Faster matrix wear. European cobalt-bond blades on Malaysian aggregate vs. their home market.
12mm
Segment height. Coolman C-Series sandwich cobalt segment, current generation.
38m
Cut length before re-dressing on a Merdeka 118 G60 slab. European baseline: 4 m.
DWG · CL-SS-012 · SANDWICH COBALT SEGMENT · CROSS-SECTIONSCALE 4:1 · ALL DIM. IN MM · REV. C · 2026-04
Sandwich cobalt segment, current generation. Three matrix layers of graded hardness laser-welded to a tensioned high-carbon steel core. The soft centre cobalt releases diamond before the outer matrix glazes — the wear rate matches the work, not the bond's original calibration.
The workshop the bond is built in.
Selangor, Section 14. Every segment we ship is pressed, sintered, and laser-welded in this single building. Every blade returned at end-of-life is sectioned here. The kilns are the same ones Coolman started with — the bond formulations are not.
A letter from Alan
When I started in the cutting trade in 1998, I thought I knew what a good blade was. Nine years later, when I founded Coolman in 2007, I knew I had been wrong. A good blade is not the one with the best segment formulation on paper. It is the one that finishes the cut on the night the contractor cannot afford to fail.
Coolman is built around that single sentence. Every blade we ship is engineered for the kind of cut that breaks weaker blades: Malaysian aggregate, hard rebar, long pours, monsoon damp, a foreman with three jobs running and no time to nurse a slow tool.
I started Coolman because I had watched too many contractors get sold a blade by someone who had never been on site at 2am. That has not happened to a Coolman customer in 19 years and it never will. If your cut goes wrong, you call me. Not a hotline. Me.
The next pages are not marketing. They are how we work, what we have learned, and the jobs that taught us. If you read them and we still feel right for your worksite, we should talk.
Alan
Founder, Coolman
The quiet door
The full range, in stock and ready to ship from Selangor.
No catalogue front. No PDF download chase. Just the inventory, the spec, and a phone call away if the blade you need is not the one we list.
247SKUs in stock
100 to 900 mmDiameter range
~500Active accounts
2 daysDispatch from Selangor
How to start the conversation
Three ways in. WhatsApp is the fastest.
Most cuts begin with a phone call. We don't hide ours.
Office
Selangor office line
Speak to the team about an order, a dispatch, a returns question. Mon to Sat, 8:30am to 5:30pm.
Call the officeOn site
Site visit form
If the cut is unusual, we'd rather come and see it than guess. Tell us where and when.
Request a site visit