Bed lowers too far down after print is done.

How can I stop the printer bed of my BFB 3000 Plus from moving too far down (on the z-axis) after a part is complete? The BFB 3000 lowers the bed until the bed drive coupling is driven into the stepper motor at the bottom of the printer. Ideally, I would like the bed to lower until about 2 inches space exists above the stepper motor.

Is there a software or hardware solution that can solve my issue?

Could I use a limit switch and connect to the BFB controller in some way?

Can I turn off the bed lowering operation after part is complete?

Might I use a post operation GCODE to limit the bed lowering operation?

I hope someone has an answer for me.

-Ken

What software are you using to slice your models?

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I'm using Axon 2 for converting cad DXF to BFB file.

I'm using BFB 3000 Plus Firmware: version# 4.1.2d

I believe the downward movement of the bed when a part is completed is caused by actions within the firmware--not the CAM software -- but I'm not positive on this matter.

-Ken

Is the BFB file just a renamed gcode file? If so, open it in a text editor. Look at the last few lines of code and see if there is a command that is driving the bed beyond your max Z height.

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Thanks, Cameron. Just to give you an update, I received a response to a support ticket I opened at Bits and Bytes:

Assigned to: SiymonBFB
Created: kjhuebner at Mon, 2013-11-04 08:58
Status: Open (Ticket / Priority Normal)
Case ID: Hardware: 1331-8193

Submitted by SiymonBFB on Tue, 2013-11-12 05:02.
Assigned: Unassigned » SiymonBFB

Hello,
I'm afraid there is no Gcode to control this as it is hard coded into the firmware. You can stop the bed as it is going down by pressing the function button on the printer when the print has finished.

Regards,
Simon

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KENS SOLUTION #1

So after reading Simon's note above, I came up with an idea that might avoid the firmware "Bed Lowering" operation.

I put a post script Gcode that does the following:
1. Lower the bed to the desired position. Example: G1 X1.00 Y1.00 Z8.00 F1100.6 which I believe moves bed down 8.00 inches.
2. Add a Gcode to pause or hold the Gcode operations. Example: [elco.crsndoo.com]

Then I manually press the Esc or Function key on the BFB controller to abort the Gcode, and return to the controller's main menu.

This approach automates the part finished procedure. As no rational person would wait 2 hours to finish printing a part, and then press the Function key at just the right time to abort the bed lowering operation.

However, I hope someone might find an electronic solution: like using a limit switch connected to some line off the BFB controller or printer head.

Ken