Thread: Bandsaw Speed

Putting on my physics hat for a second ......
If the blade is running at 900m/min and you know the length of the blade then you can calculate the rpm's .... and be able to compare .... I think this should be right ....

RPM could refer to the motor, the wheels, or the blade .... but assume the simplist answer and it will be blade speed, then follow stinkies advice. RPM x Blade length = meters / min (assuming blade length in meters)

Sir stinky,

I think you meant if you know the diameter of the wheel, not length of the blade

If you know your wheel diameter, you can work out how how much blade it will move with each revolution:

Pi * 355mm (for 14") = 1115 mm per revolution

If 420 revs min then 1115 mm * 420 = 468300mm or 468 metres per minute

if your wheels are a different size or different RPM just substitute figures,

Hope this helps (and hope I am right )

Re-reading above answers... above is true if quoted RPM is for the bandsaw wheel (Sorry Sir Stinkalot, did not even think that RPM might refer to the blade). 420 RPM looks a little slow for a motor RPM? If RPM refers to revolutions of the blade, then use length times revolutions...

Cheers...

Right... they are both advertised at 14 inch and both have 2490mm bands.
Therefore the one with the 900m/m does 361 revs and the other 420 revs. Right?
Which one is going to cut better if all else is equal?

ps. thanks for all being up at 3.31am according to the forum, I realise that the concensus of opinion is that the ES is 2 hours ahead of us but we now know that WE are 8hrs in front!

Cheers
Alf

Alf

sorry, but I don't think your last calc is right - one rev of the band doesn't equal one rev of the wheel.

900 m/min on the surface of a 355mm dia wheel of 1115 mm circumference equals 807 rpm for the wheel - nearly double the 420 rpm quoted for the other one.

the motor should have its speed stamped on it. Multiply that by the ratio of the diameters of the two pulleys to get the speed of the bottom wheel.

cheers

Colin

Hi Alf, some bandsaws are capable of having a pulley function allowing for a range of speeds available by moving the belt across the pulley optioned.
This may well be where the confusion comes from as one states a lower speed available opposed to another quoting the higher speed option.


Would be interesting if manufacturers offered up a variable speed option as they do with Lathes mind that option could confuse folk also.
Good Luck in your research
Cheers

Guys,

Chris is spot on with his calculations.

Bandsaw speed is advertised as "blade cutting speed" expressed as xxx FPM (feet per minute) or xxx MT/MIN (Metres Per Minute)

Or they advertise the "speed of the wheel" expressed in RPM (Revs Per Minute).

Use Chris's formula to work it out for your machine. Wood work machines use 2000-3000 FPM while metal cutting machines use about 40 FPM.

Glen

A nifty little program that I have found called "versaverter" that converts just about any units. Helpful for converting imperial to metric...

http://pawprint.net/vv/