Slic3r sending extruder off bed

I have just built a reprap Prusa i3 and am using Slic3r and Repetier just downloaded a few days ago. When I load a file and slice it, the positions for the x and y axis are off the bed. I checked all the settings and they are correct: bed size 200 x 200, x max 200, y max 200. Yet the Gcode starts the print at x 278 y 289. What can I do to make it stay within the parameters I set?

EDIT: I checked some things in the settings and made sure they are all correct. Then I checked positioning using M114 and that was all correct. Then I loaded the file again and checked the position as I moved it around the print area. I found that the minimum position was x210 y210, which, of course, is completely wrong. I used the command G1 X0 Y0 Z0 to put everything where it should be when homed, and set the object position to 0, 0 as well then sliced again. It gave me a warning about being out of the print area, but the positions in the Gcode were correct: x93 y93, etc. It also seems that where it starts doesn't match where it homes to even though it knows the position at home is 0, 0, 0.

Is there some way to make this work correctly without the extra steps? I really don't want a blob of plastic in the corner of the bed because I forgot to reposition the object before slicing.

Edited 1 time(s). Last edit at 02/21/2015 05:58PM by PerfectTommy.

For some printers the origin (under Printer Settings) needs to be set to 0,0. For mine, that was wrong, it needed to be set to the middle of my bed dimensions. So for my 225x145 bed, I set the origin to 112.5, 72.5 and it worked fine.

In Slic3r, in the Printer settings you both the size of the printing bed and the position that Slic3r should consider to be the center of the printing area. The center, not the origin. If they are not actually in the physical center of the bed, then the print will be offset accordingly.
For example, if you have the size 200x200 and the center (200,200), everything will be positioned (in G-code) completely out of the bed. Even a center of (200,0) or (0,200) will have the same result.
In most situations, you will have to set the values of the center in... center, i.e. (100,100) for the example above.
You can use these settings (center position) to have the part(s) aligned automatically by Slic3r in the center of the platter area in the window, but actually printing in another area of the bed, but simply specifying an offset of the physical center.
Continuing the example, It you have a piece that do not exceed a quarter of the table area, you let in center on the platter, but just specify the center to be (150,150) if you want to print it the corner opposite to the origin (well, which may not be always the homing position

Quote
JasonMBryant
For some printers the origin (under Printer Settings) needs to be set to 0,0. For mine, that was wrong, it needed to be set to the middle of my bed dimensions. So for my 225x145 bed, I set the origin to 112.5, 72.5 and it worked fine.

I wondered about that but I wasn't sure which settings to change. Did you change the Printer Shape settings in Repetier? And I was afraid that it would simply add the changes to the already wrong values, i.e. changed to 200, 200 would make it try to start at 410, 410.

Quote
3Dmaker4U
In Slic3r, in the Printer settings you both the size of the printing bed and the position that Slic3r should consider to be the center of the printing area. The center, not the origin. If they are not actually in the physical center of the bed, then the print will be offset accordingly.
For example, if you have the size 200x200 and the center (200,200), everything will be positioned (in G-code) completely out of the bed. Even a center of (200,0) or (0,200) will have the same result.
In most situations, you will have to set the values of the center in... center, i.e. (100,100) for the example above.
You can use these settings (center position) to have the part(s) aligned automatically by Slic3r in the center of the platter area in the window, but actually printing in another area of the bed, but simply specifying an offset of the physical center.
Continuing the example, It you have a piece that do not exceed a quarter of the table area, you let in center on the platter, but just specify the center to be (150,150) if you want to print it the corner opposite to the origin (well, which may not be always the homing position

That was the first thing I checked. The size is 200x200, which really should prevent any values outside of that range. The center is set to 100, 100. That's why I can't figure out where Slic3r is coming up with these other values; there just isn't anything I can find that would make it do that. And the incorrect positioning seems to be in Repetier since it shows the wrong values in the Object Position window. Maybe I should post this in the Repetier thread?

Indeed you should Or better report to the moderator suggesting to move the entire thread.

I am new to this forum and hope to learn a lot of things about 3d printing

Has this issue been resolved.......if so, please point me in the right direction as I have the same problem.

Thanks guys !

I encountered the same problem when I set up my new printer 2 days ago. I think I now have a "fix" for it. Under printer settings and printer shape tab, change the "Bed Left" and "Bed Front" setting to 0 (Not sure why 200 was suggested in the Configuration Manual).

Thanks, I shall try this and post back.

The other confusing issue is that it seems as though I am looking at the printer from the wrong side................. I think the longer past of the Y axis should be towards the rear of the machine because if I print a bracket for example and I have the long Y end towards myself then the part is a mirror image on the Y axis. So maybe I have the machine back to front is which case the settings will make more sense !

Sorry guys......got some "brain fade". I just rotated the drawing and all is well. I can now look at my machine from the front again !
The settings to 0 and 0 works correctly as well .