At KR Saws we strive to provide our customers with the most comprehensive technical band saw blade and circular saw blade support that the UK metal cutting market has to offer.
We are backed by our parent companies Kinkelder and Roentgen the worlds premium manufacturers of band saw blades and circular saw blades, our five dedicated UK application engineers have a wealth of knowledge and experience cutting a vast array of metals such as steel, stainless steel, titanium, Inconel and other aerospace alloys. Our vision and goal is to assist customers whatever their requirements from improving production rates to increasing tool life.
We also offer a saw blade training course to machine operators that can be completed on site or at our head office in Coventry. This training can be undertaken by operators whether they are new to the industry or experienced. The training includes, how to improve blade life, good and bad sawing practices, problem solving, feed and speed rates, health and safety, saw blade handling and more.
Have a look at our video from the importance of band and circular saw machine operator training.
Technical Videos
FAQs
Band saw blade breakages are often a result of machine fault, operator error or a welding problem.
Firstly we must diagnose where the blade breakage has started, either from the back edge of the blade, the gullet of the tooth or the weld. Often the easiest way to do this is by putting the blade under pressure by hand bending it. When doing this it should highlight any other propagating cracks around the blade.
If the cracks have occurred from the gullet there are two main causes;
- Cutting too fast through the material (over feeding)
- The guide arm is too wide, this puts pressure on the blade where it twists around the machine
Alternatively if cracks have occurred from the back edge of the blade, the usually diagnosis is the blade is rubbing on another part of the machine usually the top carbide pad or the lip of the wheel (due to a band wheel misalignment problem) This friction created by the rubbing generates heat and that heat causes the blade to start fracturing.
The other option is a weld break which is very easy to identify, the weld is clearly defined on the blade (there should only be one weld) and if there is a straight breakage from the front to the back of the blade in the weld area then this is a result of poor welding from the supplier.
At KR Saws we guarantee all of our band saw blade welds, any blades that break on the weld prematurely are replaced FOC (after inspections)
The first thing to always explore is the feed and speed parameters you’re working too which is defined by the material and diameter being cutting.
If the blade is cutting too fast through the material (band speed M/Min) this can create excess heat and this causes the blade to blunt prematurely. If the feed rate is too high (mm/min) this can also generate extra heat and also the blade to clog up with metal swarf.
A simple tip to identify if you’re cutting too fast is by looking at the swarf that’s been produce, ideally the swarf wants to be curled in the shape of a 6 or 9 and silver in colour. If the chip thick and blue in colour this means your cutting too fast causing a lot of heat to be produced.
Another common occurrence we find is that the swarf brush on the machine is inactive, damaged or worn. If the swarf brush does not engage with the band saw blade teeth there are several things that this can cause, for example the teeth can clog as a result of swarf getting stuck in the tooth and this can cause the teeth to strip off the blade. Also during the cutting process, the swarf yields a lot of heat and if hot metal swarf Is not removed from the tooth it may transfer in to the blade causing it to blunt quicker.
The other way to improve blade life is by running the blade in properly when it is installed, Roentgen recommend reducing the feed rate by 50% and the band speed by 25% this creating a cutting radius on the tooth. Failing to do this can cause the tooth to fracture or damage prematurely.
Other ways to increase blade life is by ensuring your coolant levels are correct, we recommend a level between 8% - 12% depending on the material that you’re sawing.
Finally using the correct tooth pitch, if you have a fine tooth blade with too many teeth engaged in the material this can cause excess friction and heat, along with the blade clogging with swarf. Alternatively if the blade is too course you may not have enough teeth engaged, this can produce more of a ripping type cut, this may result in teeth fracturing or teeth stripping completely off the band saw blade.
A swarf brush is one of the most under-appreciated component on the band saw machine. Basically the tooth cuts through the material and the swarf brush which is located just after the cutting process (if installed correctly) helps the metal to be displaced from the tooth. This is important for quite a few reasons such as;
1 – A lot of heat can be generated during the cutting process which and if the metal does not evacuate from the tooth this heat can be transferred in to the band saw blade causing it to overheat and wear prematurely.
2 - If the swarf is not removed from the tooth you, the situation can occur where the metal welds itself on to the tooth, this in turns creates a different cutting angle which can produce poor surface finish or the cut to be out of tolerance
3 – If the swarf welds to the tooth this can also cause the blade to clog up and this over clogging can result with the teeth being stripped off the blade.
4 – Swarf that has not evacuated from the tooth can end up falling out elsewhere around the machine and overtime this can cause major problems, a consequence of swarf building up behind the band wheel for example is bearing damage creating misalignment in the band wheels.
See our catalogue below for possible failure causes:
