Proper BS Blade Guide Bearing Adjustment?

[John McClanahan]

We have a bandsaw at work that currently uses special brass blade guides. The saw is for a specific purpose and is rather old, built in the late '40s or the '50s. Parts are getting hard to find, so I would like to convert the upper blade guide blocks to bearings. I'm not sure if there is room to change the lower.

Typically, bearing guides are set so the bearing doesn't quite touch the blade. My question is, why not let the bearing run lightly against the blade? I want to eliminate as much blade flex as possible.

I should also mention that the blade speed is around 5400 fpm. About double the speed of woodworking saws. Since bearings are used in high speed tools like routers, I don't see where letting the bearing run against the blade would cause a problem. Any thoughts?

Thanks, John

[Eiji Fuller]

Friction will heat up the blade.

Also 5400 is not an overly fast speed for a wood cutting bandsaw. My Felder runs at about 6000 and many industrial machines run at 8-12k.

[Stephen Cherry]

you would want to make sure that the weld in the blade is well ground so that the blade doesn't have a thick spot that would bind as it goes through the guides.

[Pete Bradley]

Personally I'd stay with the blocks. Even if the blocks are a nonstandard size you can probably get some made cheaper than a new set of rollers.

Normal clearance for blocks is about .004. Recommended clearance for most rollers is .001, so the rollers do run practically at the band.

Pete