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I noticed my nozzle lifts up about .23mm-.50mm at 50-90mm from the center of my bed and inbetween the towers. Doing the calibration,the axis' and center are great, but traveling the outer diameter my nozzle convexes between towers. Im using the glass bed and have the nozzle and bed heated while doing this.

There is a value in the firmware called printer_radius. If you're using repetier 0.90 you can change it in the EEPROM (there I think it's called horizontal radius.) http://forum.seemecnc.com/viewtopic.php?f=39&t=987 Geneb's manual should help you with this.

It works for the center of the bed, not the outer radius. Calibration per the manual is all set, but the outer diameter between the towers are the issues.

You're saying that the 4 calibration points in the manual are the same, but when the head moves between the towers it arcs?
IF that is the case you likely have a geometry problem, you'll need to verify everything is square.

I concur with the geometry problem diagnosis. Squareness is a good start, but might not be enough.

When you say 0.23-0.50 mm, you're saying that the lift isn't the same at all three between-tower points, i.e., it's 0.23mm at one, 0.5mm at another, and possibly in-between for the third?

Two things helped me clear this up, and even then one step may have been unnecessary. I had first cut out a chunk of the snowflake undernear the heat bed to give the wires room, and this seemed to help my calibration stay between heat cycles of the bed.

The other was I rechecked and reworked my build with a proper precision square where I checked 3/4 of the side on each tower, and on each side of the belt for the center facing side of the tower.

Did you actually go through the step of setting the printer radius, like it says in the manual? What you're talking about sounds exactly like what that fixes. The "four-point" calibration nails down the middle and the edges, but it won't know how to get between the two accurately unless the radius is correct.

It's been a few months, I'll have to relook at that. When I was talking .23-.5mm, I was referring to the arc between towers that the nozzle made. As it left the Y tower it gradually arced to its high point of .5 then back down to bed level as it got to the X tower.

As far and resquaring, Again ill need to find it in the manual, reread, and figure out what it all means.

I did exactly what was called for as far dealing with the printer radius in Arduino to fix the convex I had in the center of the bed. Also, early manuals (Jun-Aug) had me set printer radius at 280mm. Then the new ones came out saying 140mm and Seeme confirmed it. Those are the only two references of printer Radius that I know of. If theres a diff one, let me know where to look. For any of this...