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Slop in the Rails Adversly Effects Alignment

JPG

dusty wrote Where did 1/32" come from?

Later version has over 1/16" slop.(0.070)

Original version had slightly over 1/64"(0.020)

510 Table Rail with Table Tube Secure and Unsecure.jpg

OK half the slop.

dusty

JPG wrote OK Dusty. When stacking tables horizontally(main-float...-aux) the varying vertical displacement of the connecting tube within the rail tube will result in the table tops varying elevation. Granted that may be small, but it drove Ed in Tampa berserk. The 520 eliminates that by providing a consistant rail to table top dimension by virtue of the gauge(or thy procedure). Also a poster here also helped that by tapped holes in the bottom of the rail tube thus causing screws similar to the 520 to clamp the connecting tube to the top of the rail tube.

One thing I have not highlighted here is the newer version's increased clearance between the connecting tube and the rail tube. That exacerbates the problem.

Keep in mind there are two issues. Vertical top co-planar and rip fence skew.

I've been wrestling with this since you posted it. Why do you believe the table tops will vary in elevation. The Table Rail and the Table Tube will become locked into a position where their axis of rotation are co-planar and will then seek the elevation of the Table Rails. I do assume that the Table Tubes are simultaneously secured in their respective Rails. The ultimate objective being to get all tables co-planar (plus/or minus some yet to be defined level of precision).

JPG

It is the magical, consistent, repeatable alignment of the connecting tube within the rail tube that simply is NOT assured. I realize thee wants to assume that happens with flat ends of the clamping screws/knobs, but it is there the the misalignment may occur. There is no restraint that prevents the connecting tube from aligning off center with the rail. The at rest positioning by virtue of gravity places the connecting tube center slightly below the center of the rail.

As the clamping screw is advanced, the connecting tube is pushed outward away from the table and must slide(or rotate) upward along the bottom half of the interior of the rail. As the center of the connecting tube approaches the center elevation of the rail, any torque applied by the screw MAY push the connecting tube either upward or downwards away from the rail center depending upon which side of the screw end acquires more traction than the other side.

The 520 eliminates all this by way of the vertical restraint in the top interior of the 520 rail extrusion as well as the direction of the clamping screw advancement(vertical rather than horizontal).

Yes it is subtle and minimal, but it can occur. Ed in Tampa had difficulty adjusting to that POSSIBLE/INCONSISTENT vertical variation. Perfection is indeed an elusive goal. It is tolerance(both physical and mental) that defines success or not so.

Hope that helps.

dusty

I may have to modify my long standing opinion about this.

All of my previous testing that I can attest to was done on a 510 with an extension table. In this configuration the tables were coplanar and an unsecured table tube would lie on the bottom of the Table Rails.

I woke up two nights ago thinking about a possible fallacy in this thinking.

If I begin the test with a 510 Floating hanging between an Extension Table and the Main Table and the table Tube is secured in the Main Rail and the Extension Rail a different test environment is created. Initially I was pushing on and expecting to move the table tube. In this revised setup, I am attempting to move the floating table rather than the table tubes and the initial results are a bit different, Much less consistent. Howevr, I can get more repeatable results if a put a little upward lift on the floating table while securing the thumbscrews.

Case is Still Open ( at least for me).

JPG

Manual biasing the table may create more repeatable results, but it contaminates the process.

dusty

JPG wrote Manual biasing the table may create more repeatable results, but it contaminates the process.

This is not a scientific study. The primary objective is to ascertain whether or not a floating table can be properly positioned and can a user SAFELY mount and use a rip fence on that floating table.

If manually biasing the table makes that a reality then the users al benefit by knowing that.

dusty

I simply hung a floating table on a table tube. Full weight of the table pulling down positions the table tube to one side of the rail. Ten out of ten times tightening the thumbscrew repositioned the table tube where it should be.

This feels like the "end of the parade". It is my conclusion that the 510 thumbscrews work just fine and I believe are no less effective than the 520 rail system.

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