Delta Unisaw blade raises up when starting..help!!


My unisaw blade raises (jumps) approximately 1/4" along with the trunion when I hit the start switch. It does return to original position once the motor has started. I have had the trunion out and everything appears to be fine. Has anyone had this problem or have any ideas. Thanks!!
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New saw, old saw, Is this a new development or has it always done this. Most cabinet saws do start with a jolt but the blade raising 1/4" is not normal. Could the arbor bearings have way too much excess play?
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The shaft that raises the blade needs to have the play adjusted out of it. It is moving back and forth when the saw is started and most likely also moves while cutting under heavy load.
Kevin
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wrote:

Had the trunion out? Then you've taken the internal mechanism completely apart? Why?
If that is what you did and it is the only way to remove the trunion, look at the alignment of the elevating worm gear to the gear segment on the arbor bracket. Is it centered in a linear direction along the shaft. If not you will get too much backlash and the mechanism will not be tight. It is originally fixture set and the mounting shaft should should be scribed prior to removing the arbor bracket assembly it so that it can be replaced in the same place.
Did you put the shaft pins back that are contacted by the lock knob to lock the elevating shaft. Easy to miss or forget and if you didn't it will not lock properly.
When you reassembled did you clamp the yoke/trunion assembly between the front and rear trunion brackets before you torqued the trunion bracket bolts down? If not the yoke/trunion assembly will have linear play between the trunion brackets and the elevating lock will not hold.
I might offer additional help with more infor. Delta tech service should also be able to help you.
Frank
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On Mon, 07 Nov 2005 07:25:21 -0600, Frank Boettcher

that much jump in the elevating mechanisim, I would consider the saw unsafe to use until you resolve the issue.

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