The most common two questions asked when a customer is investing in a coldsaw is ‘what tooth pitch?’, and ‘what speed?’. This can sometimes be hard to answer exactly. Having 180 teeth on a 250mm blade is much finer than having 180 teeth on a 350mm blade. This is because the same number of teeth would be spread over less of an area. However, you can certainly maximise the life of your blade and increase the quality of your cutting. You can do this by using the below tables for guidance.
Something that differentiates the CS-350-DM from other models of coldsaw from other models in the range is the variable speed inverter. This feature allows operators to change speeds extremely precisely between 24 RPM and 120 RPM. Perfect for adjusting between cutting hard materials like stainless, through to soft materials like aluminium, on the fly!
It’s important to remember all these values below are ballpark figures. Nothing is exact. This is especially true when it comes to manually descended machines like the CS-250-DM, compared to semi-automatic machines for example.
The first thing we must do is work out the circumference of the blade with a little math. By using π, also know as Pi (which is 3.141) we can work out that the circumference of a blade which is 350mm in diameter is 1099mm (D x π = 1099). We’ll keep this information for a little later.
Now to look at the first Application Matrix for High-Speed Steel (HSS) coldsaws blades below.
In the body of the table, you will find numerical values. These numbers relate to the distance (in millimeters) that should ideally be between each blade tooth. This is called Tooth Pitch.
Using 20mm solid rod as an example material, we can locate the size across the top, and our material down the side to find our number. In our example, it would be 7. This conveys 7mm between each tooth on a blade.
To work out what that means for your blades total tooth count, we must use the circumference we calculated a little earlier. To find this tooth count we divide the circumference (1099) by our tooth pitch number (7).
1099 ÷ 7 = 157
This suggests that we ideally need a 157-tooth blade to cut 20mm solid rod if the blade is 350mm in diameter. Sometimes this blade may not exist, but as mentioned before, these are ballpark figures. You can use this data to conclude that a 160-180 tooth blade would be the ideal range for your application.
This calculation can be copied for any diameter blade!
Next, we can take a quick look at ideal speeds for materials.
Using the wrong speed for your material can be disastrous for the life of your blade. For example, running too fast against nickel-high materials such as stainless can almost immediately dull your blade. Alternatively, running too slow against soft materials such as aluminium can very easily clog up your blade gullets. This in turn damages the machine’s motor.
Unfortunately, this guide displays speeds in meters per minute, whereas the CS-350-DM displays speeds in revolutions per minute. There are, though, a few ways of interpreting your meters per minute (mpm) to revolutions per minute (rpm).
The first method involves complex mathematics which we will skip for this layman’s guide!
Fortunately, Kinkelder have supplied a handy little tool for converting MPM to RPM and vice versa. You can find that page HERE for your convenience.
However, as mentioned several times, these values are mostly guides. Due to how close a 350mm blade is one metre (1099mm), it’s quite possible to accurately use educated guesswork to determine the preferable speeds for your material. You can do this by compensating for the 99mm addition.
Using our example material once more (20mm solid rod), we can also imagine that this material is stainless steel. Following the information on the table, preferable speeds for round stainless is between 5 and 30 metres per minute. This corresponds accurately to the fact that you should never cut stainless faster than 25-30 RPM.