Finalizing Main Table Alignment

[dusty]

I attempt to get to within less than .005" for the initial alignment. I am then saying that normal day to day like activities does change those results (whatever they were) but seldom more than enough to exceed the original objective.

All of this is dependent upon all locks being secure and when I want to make absolutely certain that nothing moves (excessively) I utilize the table rails (front and rear). This is about the only situation where I use the 5' rails.

I am saying that I experience a much more stable Mark than you describe.

The subject of this thread, however, was to determine a way to minimize the movement that tends to result as you tighten the trunnion bolts. Sometimes, I find that to be a real crap shot. Other times it goes very smoothly. Must be technique.

[JPG]

I think all this lamenting over single digit thousandths is worrying about gnat's hairs.

[dusty]

I think all this lamenting over single digit thousandths is worrying about gnat's hairs.

You might be right so don't get caught up in that discussion.

Ease of alignment (using the .005" guide line) was the intended subject of this thread. It was/is not about achieving accuracy. The desired level of accuracy can be had by just doing any of the other proposed procedures. Even the miter gauge and stop rod procedure works that well (if you are careful).

[dusty]

Ease of alignment (using the .005" guide line) was the intended subject of this thread. It was/is not about achieving accuracy. The desired level of accuracy can be had by just doing any of the other proposed procedures. Even the miter gauge and stop rod procedure works that well (if you are careful).[/quote]

520, SN112291 Stabilize the Main Table During Table Alignment.png (57.6 KiB) Viewed 7193 times

The question is "How to keep the table from shifting while securing the trunnion bolts".

[JPG]

Back to the 'topic'. I agree with what has already been said re snug with light/soft hammer and gradually increasing torque.

That does require frequent checking to insure it is not shifting from desired alignment.

The dual gauge would make that checking much easier.

[Ed in Tampa]

I think to answer this question you first have to define what is effecting the alignment and why during the tightening process. Yes there is a torque involved when the bolt is tightened.
But should that move the table toward or away from the blade? Why not toward the front or back. Is there a way to minimize this?
There would be gravity involved when the table is tilted to tighten the other bolts could this be minimized.
Is there a way to lock the table into place on the trunions until the bolts are fully tightened?

Right now I do not think anyone has conclusively defined why the alignment changes.

Could it be something else other than the torque when tightening the bolts. Movement in trunion piviots?
Torque imposed by table lock?
Locking the table into position also requires a way to lock the trunions. Just holding the table would still allow the trunnions to shift.

Whole bunch of thought no real solutions but I think we first must find why the alignment changes and stop assuming it just the torque from tightening of the bolts.

[dusty]

All good input.

[quote]Ed In Tampa Wrote: But should that move the table toward or away from the blade? Why not toward the front or back. Is there a way to minimize this?
There would be gravity involved when the table is tilted to tighten the other bolts could this be minimized.
Is there a way to lock the table into place on the trunions until the bolts are fully tightened?[quote]

I think that it has been shown that the unwanted movement occurs when the trunnion bolts are tightened. Which direction? That is unanswered but why is it important? Any movement is unwanted.

Properly sized, this approach just might work (510 converted to 520 only). The bolts utilze threaded holes abandoned by the upgrade. The bars are set up blocks that I have in the shop and would not be part of the final. In final form it will be an assembly; not an accumulation of loose parts. The 510table rail thumbscrews have me thinking.

Align the table. Gingerly secure two trunnion bolts. Recheck/tweak alignment. Install and secure jig. Recheck alignment. Tilt table and secure other two trunnion bolts. Recheck alignment. Make sawdust safely.

Believe me - The trunnion is immovable with this installed and might even be adjustable in the final configuration.

Stabilizer 006.jpg (2.07 MiB) Viewed 7161 times

[Ed in Tampa]

All good input.

Ed In Tampa Wrote: But should that move the table toward or away from the blade? Why not toward the front or back. Is there a way to minimize this?
There would be gravity involved when the table is tilted to tighten the other bolts could this be minimized.
Is there a way to lock the table into place on the trunions until the bolts are fully tightened?

I think that it has been shown that the unwanted movement occurs when the trunnion bolts are tightened. Which direction? That is unanswered but why is it important? Any movement is unwanted.

Properly sized, this approach just might work (510 converted to 520 only). The bolts utilze threaded holes abandoned by the upgrade. The bars are set up blocks that I have in the shop and would not be part of the final. In final form it will be an assembly; not an accumulation of loose parts. The 510table rail thumbscrews have me thinking.

Align the table. Gingerly secure two trunnion bolts. Recheck/tweak alignment. Install and secure jig. Recheck alignment. Tilt table and secure other two trunnion bolts. Recheck alignment. Make sawdust safely.

Believe me - The trunnion is immovable with this installed and might even be adjustable in the final configuration.

Stabilizer 006.jpg

Dusty
Great idea but help me understand that seems to prevent lateral movement(front and back of machine) to the trunions. But parallel to blade requires a way to prevent or restrict movement left or right of the trunions. Your idea would work if it exerted pressure on the trunions 90 degrees to where you now have it, or is there something I am missing or do not understand?

[dusty]

At this stage it would be friction. Remember, I am trying to restrain nothing more than the movement created by tightening the trunnion bolts. That movement is typically minimal.

Meaningless question: how far are the trunnions able to move when you torque the bolts?

While talking about trunnion bolts, cxan anyone tell me why the washers on the trunnions are so thick (>1/8")? I understand washers but there must be some special reason for making them thick.

[algale]

While talking about trunnion bolts, cxan anyone tell me why the washers on the trunnions are so thick (>1/8")? I understand washers but there must be some special reason for making them thick.

So the bolts won't come through the top of the table?

That's a joke. Kinda.