So what if my bandsaw runs at 2x speed?

[®smpr_fi_mac®]

I'm swapping motors on my BS, but the replacement is a 3600 motor, as opposed to the original 1800.

The shaft on the two don't match, so I need to replace the drive pulley and will replace the driven pulley, too, to bring down its speed to OEM spec.

My curiosity gets the best of me, though--what detrimental effects occur if I leave the driven pulley alone?

[jlanciani]

Likely throw the tires to start. Could get ugly from there depending on what the blade does when the tires come off.

[jteneyck]

I'm swapping motors on my BS, but the replacement is a 3600 motor, as opposed to the original 1800.

The shaft on the two don't match, so I need to replace the drive pulley and will replace the driven pulley, too, to bring down its speed to OEM spec.  

My curiosity gets the best of me, though--what detrimental effects occur if I leave the driven pulley alone?

What is the stock speed?  If it's in the 1500 - 1800 fpm range you could likely double it w/o any issues.  Many BS are designed for dual speed.  John's got a valid point about the tires, but I really doubt the two speed saws have better tires on them.  More likely all tires can take that speed.  I boosted the speed on my 14" Delta by about 50% and haven't had any issues.  

John

[TDKPE]

The 14" wood (only) Delta runs at 3000 ft/min, or at least the old ones did. 2-3/4" sheave driving a 6" sheave. I wouldn't double the speed of that one. But that's just one saw out of many possibles. What's the saw, Brad?

[jteneyck]

The 14" wood (only) Delta runs at 3000 ft/min, or at least the old ones did.  2-3/4" sheave driving a 6" sheave.  I wouldn't double the speed of that one.  But that's just one saw out of many possibles.  What's the saw, Brad?

Well that explains why my wood/metal version cuts better.  It was around 2400 fpm max. before I boosted it.  Now it's around 3500 fpm.  

John

[jlanciani]

Well that explains why my wood/metal version cuts better.  It was around 2400 fpm max. before I boosted it.  Now it's around 3500 fpm.  

John

Yeah, I messed around with one of the more modern 14” Deltas I had. At about 4000 fpm the stock tires (unglued) started to lift. Ive settled on about 2400 fpm on the 14” I have now since I only use it for scrolling and detail work.

[daddo]

At that speed all you need is a flux capacitor and your off to another dimension in the time/space continuum.  

[TDKPE]

I'd also guess that it'll (possibly) wear the blade extra fast.  With a small hp motor, you can only feed so fast without overloading the motor, and with such a high blade speed, the cuts will have to be very shallow.  Each tooth taking twice as many trips through the wood, with half the cutting depth.  

That's just talking out loud, of course, but I'm sure there's some science out there on the physics of blade teeth cutting wood, though I've never been able to find any.   There is for metal cutting, though.

And with a wheel speed of 820 rpm, more or less, on the standard Delta 14", I don't think I'd want to spin that bad boy up to 1600+ rpm.  I doubt they're balanced that well, plus the issue of keeping tires in place.  And cutting efficiency and blade life, of course.

[kurt18947]

"manly" band saws - industrial types run around 5,000 ft./min. or more but they're engineered for it. The norm for 14" saws seems to be around 3,000 ft./min and I imagine you could increase that 10% - 15% or so. What boosting the speed might accomplish resawing would be a slightly smoother cut. I've noticed when resawing that if I feed slower, the surface is a bit smoother so less sanding required.Bumping up the speed would enable a faster feed rate for the same cut quality or the same feed rate and better cut quality. At least that's my theory, and worth what you paid for it.

[®smpr_fi_mac®]

TD,
It's a mid-90's Delta 14 " with riser. It's the sane one we're discussing in PM's.

I'm not seriously considering leaving the driven pulley the same. Just curious about it.