MakerFarm 8" i3v Prusa build by Printbus

[printbus]

So I found out that my z axis is ok, it was just stuck. I need to get some oil. 2 questions.
1. How do I adjust the z end stop far enough down with the couplers being in the way. It looks like I have about an inch down from the hot end to the bed. I do need to do the initial bed leveling yet.
The end stops seem to be testing ok, but doing the m119 command, is shows the X max and y max as triggered, yet the mins work fine?

1. I mention in my Z MOTOR post that a ball end driver helps with the Z endstop bolt if you are using the large couplers. You'll soon be realizing how crude the i3v approach to the Z endstop is - it is very tough to adjust it with any repeatability or accuracy. The large coupler being in the way just aggravates this. Luck will be an important part of getting a good adjustment. Before I could print a new mount for the Z endstop, I swapped the fixed spacer on the bed with another spring so I can just adjust all four corners.

2. At the home position I show the mins as triggered and the maxs as open with M119. Away from home, all show open. Are you sure you have the endstop connectors on the right places on the RAMPS board? There are -Z, -Y, and -X labels next to three rows of pins on RAMPS. Your connectors should be on those rows of pins.

[usarmyaircav]

1. I mention in my Z MOTOR post that a ball end driver helps with the Z endstop bolt if you are using the large couplers. You'll soon be realizing how crude the i3v approach to the Z endstop is - it is very tough to adjust it with any repeatability or accuracy. The large coupler being in the way just aggravates this. Luck will be an important part of getting a good adjustment. Before I could print a new mount for the Z endstop, I swapped the fixed spacer on the bed with another spring so I can just adjust all four corners.

2. At the home position I show the mins as triggered and the maxs as open with M119. Away from home, all show open. Are you sure you have the endstop connectors on the right places on the RAMPS board? There are -Z, -Y, and -X labels next to three rows of pins on RAMPS. Your connectors should be on those rows of pins.

Hi Printbus, I totally forgot about your comment about needing the ball driver, I will pick one of those up tonight. do you think having 4 springs is better than 3 and a spacer? As to the end stops, I put them where Colin said to without really looking at the board itself. could my less than stellar sodering jobs be related?

[printbus]

Hi Printbus, I totally forgot about your comment about needing the ball driver, I will pick one of those up tonight. do you think having 4 springs is better than 3 and a spacer? As to the end stops, I put them where Colin said to without really looking at the board itself. could my less than stellar sodering jobs be related?

If you have the endstop connectors where Colin shows them, and the mins work OK, maybe the right answer is to not worry about the maxs. The configuration.h file has the #defines for the pullups on the input pins for the max endstops commented out; this likely prevents the internal pullup being activated for those pins on the MEGA2560 processor. That would lead to the input being randomly read in as high or low depending on how the unconnected pin tends to float. With the #defines for the max inputs commented out, firmware likely doesn't do anything with the inputs for the max switches. Your soldering is likely fine, since the min and max endstop switches would be on separate connectors on the RAMPS board.

I prefer the four springs approach. It allows me to just get the Z endstop anywhere close, and then all fine adjustments are done in the four corners of the bed. Of course, I have thumbwheels on the corners now too. Leveling the bed takes me about two or three minutes. The stock makerfarm approach can easily take 20-30 minutes because of the crude approach for mounting the Z endstop switch, the complexity caused by the fixed corner that requires a near-impossible fine adjustment of the Z endstop, and the multitude of tools required to adjust the other corners.

[usarmyaircav]

If you have the endstop connectors where Colin shows them, and the mins work OK, maybe the right answer is to not worry about the maxs. configuration.h as the #defines for the pullups on the input pins for the max endstops commented out; this likely prevents the internal pullup being activated for those pins on the MEGA2560 processor. That would lead to the input being randomly read in as high or low. With the #defines for the max inputs commented out, firmware likely doesn't do anything with the inputs for the max switches. Your soldering is likely fine, since the min and max endstop switches would be on separate connectors on the RAMPS board.

I prefer the four springs approach. It allows me just get the Z endstop anywhere close, and then all fine adjustments are done in the four corners of the bed. Of course, I have thumbwheels on the corners now too. Leveling the bed takes me about two or three minutes. The stock makerfarm approach can easily take 20-30 minutes because of the complexity caused by the fixed corner and the multitude of tools required to adjust the other corners.

Trying to remember all your changes, did you print those thumb wheels out?

[printbus]

Trying to remember all your changes, did you print those thumb wheels out?

Yes. The ones I have now are http://www.thingiverse.com/thing:29782. On the 8-inch printer, I did have to file the diameter down a bit for the one at the left rear to clear the frame. Other thumbwheels may not have that problem.

The BED LEVELING post describes how the screws are locked to the heat bed, leading to a tool-less approach to the bed leveling. Note that I did replace the corner bolts with longer ones too, mainly since the silicone trivet I use for bed insulator is pretty thick. The thumbwheels originally used in that post didn't have much knurl, so they were later replaced.

EDIT: Of course, if you plan to implement ABL pretty quickly on your printer, the concerns on how hard it is to level the bed won't be as important to you.