Bandsaw Machine Efficiency

 
If broken teeth in a bandsaw blade is a common problem, chances are that either the machine hasn’t been set up properly, or the blade hasn’t been correctly run in. So, to help you get the maximum life from your bandsaw blades and avoid those broken teeth, we’ve developed this simple checklist.

The Machine Frequently check:
• The operation of the chip brush;
• The wear and alignment of the guides;
• The band tension with a tensionmeter;
• The band speed with a tachometer;
• The coolant concentration with a refractometer.

Tensionmeters, tachometers and refractometers are available now from your
local Trade Tools branch. We will also be happy to call in with these pieces of equipment and discuss their advantages in more detail – just let us know if you would like to do this.

The Coolant/Cutting Fluid
The coolant lubricates, cools and carries the chips from the cut. It’s important that you:
• Use good cutting fluid;
• Use the recommended concentration of cutting fluid (we can advise on the right
concentration);
• Make sure that the cutting fluid reaches the cut with low pressure and large flow.

The Workpiece
• Make sure that the workpiece is firmly clamped so that it cannot vibrate or rotate.
• Do not use bent or damaged workpieces.

When running in always use the recommended band speed but lower the
feed rate to 1/3 –1/2 during the first 10 minutes of cutting. Increase the feed rate
in stages over the next 10 minutes until you have reached the recommended feed rate.

Maximise your bandsaw Q & A

This month we will look at bandsaws and showing how you can solve some common problems to achieve maximum life and performance.

Q. I’ve noticed a lot of chips at the side of the entrance of the band into the workpiece. Is this a serious problem?
A. Yes, it is. It means that the chip brush isn’t working properly, which can cause the teeth to wear out quickly or even break. We recommend that you replace the chip brush as quickly as possible.

Q. Can I check the blade speed without a tachometer?
A. Yes, and it’s easy to do. Simply mark the loop with a felt tip pen and time one revolution. This will give you the speed.
Here’s an example:
• Blade length 7.600 mm;
• Time of revolution 10 seconds.
Formula:
60 ÷ 10 x 7.6 = 45.6 metres/min.

Q. How can I estimate the time of cut?
A. On a machine with a constant feed-rate you can calculate the estimated time of cut as soon as the band is in the cut.
Here’s an example:
• Diameter of piece is 500mm;
• Blade width is 54mm;
• Time it takes for full blade penetration is 3
minutes. Use this calculation:
500 ÷ 54 x 3 = 28 minutes estimated for
the full cut.

Q. I’ve tried bundling bars together to cut all at once but have had a lot of problems with tooth and band breakage. How can I prevent this?
A. Bundle cutting can be a tricky process, as the bars can move or spin, and this is what causes the tooth and band breakage. You can get around this by welding the ends of the bars together to hold them in place.

Q. How can I check how well the blade is cutting?
A. Check the chips. If you keep chips aside at several stages of the operation and check their size, you can see the effect of changing parameters during the cuts.

any questions?
We’ll be happy to answer any questions you
have about cutting, threading or hand tools – or
any problems you may be having with machines
or tooling in your workshop.
Phone 0800 4 TOOLS or email sales@tradetools.co.nz for a Bandsaw Checklist, or to arrange a visit from a Trade Tools.
Representative to check your operation. www.tradetools.co.nz/blog/resources

 

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