Bandsaw table vibration

[JakeS]

I moved my bandsaw the other day, which involved lifting it off of the short table it was stood on, moving the table to a new position and lifting the saw back onto it. Both lifts were accomplished without holding it by the table, but part-way through use yesterday the table started to vibrate something rotten. It wasn't doing it when it started up, but at some point through the session it started - quite suddenly, and now it's vibrating quite heavily every time I run the saw.

I've tightened everything I can see that might be tightenable, and it cuts fine if I hold the table steady, but I'm at a loss to understand what could be causing it - does anyone have any ideas? It's a 10" SIP, if that helps. The best I've been able to do is narrow it down that the trunnion seems to move and the frame of the saw itself doesn't seem to - only the transmitted reverberations of the table - but I've locked the trunnion good and firm and double-checked the bolts on the mount, so I'm out of ideas... :/

 

[CHJ]

You need to find out what has become unbalanced or come loose in the drive chain to cause the vibration.

Remove the drive belt from the motor.
Check motor Drive Pulley is firm on shaft.
Run motor, does machine vibrate.
Remove blade from wheels.
Check top and bottom wheel mountings for play, check for loose/rough/seized bearings and spin by hand to check balance, have any of the little weights come adrift or is there any excessive dust build up.

 

[Tony Spear]

My first thought would be that. as you've moved the table the problem lies there.
Try running the saw with something (or somebody!) holding the table you've got the saw standing on.

From my experience as a pump engineer, I can tell you that the minutest vibration at the natural frequency of the rotating element may take on an acceleration which can shake the machine to pieces! (ask anybody who's driven a 2CV along some French roads!).

For what it's worth, we had a couple of pumps installed in the West Country that were of a design that made the rotating elements very hard to balance and when they were first started they shook so much that nobody would go near them. After much too-ing and fro-ing, one of our really expert engineers told the site guys to tighten the holding down bolts whilst the pumps were running. Problem solved!

 

[Hudson Carpentry]

My first thought would be that. as you've moved the table the problem lies there.
Try running the saw with something (or somebody!) holding the table you've got the saw standing on.

From my experience as a pump engineer, I can tell you that the minutest vibration at the natural frequency of the rotating element may take on an acceleration which can shake the machine to pieces! (ask anybody who's driven a 2CV along some French roads!).

For what it's worth, we had a couple of pumps installed in the West Country that were of a design that made the rotating elements very hard to balance and when they were first started they shook so much that nobody would go near them. After much too-ing and fro-ing, one of our really expert engineers told the site guys to tighten the holding down bolts whilst the pumps were running. Problem solved!

Aye you can shake many things apart once its found its resonant (spelling) frequency