Saw Vibrations

[Vector01]

Hi All:

 

I thought I would see if there was anything I could do about the vibration in my Hitachi CW40 scroll saw at full speed. I had posted my initial thoughts on this saw a while back. http://www.scrollsawvillage.com/forum/viewtopic.php?f=2&t=355 All in all the performance was good and I've had no major problems with it.

 

Since I like to tinker with anything mechanical, I pulled out the parts diagram and took a look see. I checked the motor mounting screws and they were all tight. The uppper and lower arm pivoting pins seemed to be tight and lubricated. The upper and lower arms did not show any unusual lateral movement. The tensioning mechanism at the rear of the saw is pretty much unaccessible unless you want to tear down the saw case, so I left that alone.

 

The last area that I thought could cause this problem was the lower arm assembly. I noticed that the connecting cam/eccentric was 3/8" of and inch forward of it's most rearward position (not sure if this is the correct name for this part) on the drive shaft.

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I ran the saw from zero to full speed and noted when the vibrations started. Loosening the set screw, I set the cam to the rear (closest to the motor) retightend and ran the saw again. The vibrations were reduced. I continued this process until I found the sweet spot. For this particular saw I found the vibrations at full speed had been reduced by half when I set the cam approximately 1/8" of an inch from it's most rearward position.

 

I would suggest using caution when making any "non factory" authorized adjustments to your saw. You could void your warranty and possibly cause damage to your saw. For me this adjustment helped for this saw.

[Travis]

That's a great tip. I'm not mechanical enough to tinker around with stuff like that. I didn't even know you could make that adjustment. I usually just bolt the saw down as tight as I can. There are a couple areas on my speed dial that causes a lot of vibration. I think it's mostly due to harmonic vibration, which amplify vibrations at certain speeds (that's the most I remember from my HS physics class, anyway. )

[greasemonkeyredneck]

Congrats on your saw improvemnets. If anyone is feeling adventerous, I highly recommend looking at any improvement you can make to your saw. Tiny adjustments here and a tweak there and you'll think you're working with one of the most high priced luxery saws. I'm all the time tinkering with something on my saw. Sometimes I make things better, some times worse. For now though, my tinkering has me a $59 (on sale) Delta that5 has virtually no vibration at all. Now, my Craftsman, that's a whole different story. We won't talk about that one for now.