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The only other problem with you print head hitting the bed is that it might make the nozzle's tip less than perfectly flat. Because of that you might see little variations in the plastic that change dependent on the direction for the first layer and small layer heights. Luckily it is fixable, and besides that it is one of the cheaper and easier parts to swap out. I have something like 4 nozzles for my hotend and none of them have gotten away with out battle damage (glass bed has won all but once so far). I agree though it is frustrating and a little sad to watch something go from like-new to very used condition in a split second.

Thanks for that info, LordBinky. I wish there was a way to mark each *tip* that I've encountered while reading through these forums as I'm sure I'll forget things as I get further along in the process

I took a look at the nozzle under a magnifying glass and didn't notice anything particularly bad, but I'm not 100% certain what to look for anyway. I'll order a spare nozzle or two once I get things working.

dpmacri wrote:Thanks for that info, LordBinky. I wish there was a way to mark each *tip* that I've encountered while reading through these forums as I'm sure I'll forget things as I get further along in the process

I took a look at the nozzle under a magnifying glass and didn't notice anything particularly bad, but I'm not 100% certain what to look for anyway. I'll order a spare nozzle or two once I get things working.

You can create bookmarks by going to the bottom of the page and select to bookmark topic. I use Firefox as my browser and use a bookmark toolbar to keep track of what I
feel are important topics. The advantage of the bookmark toolbar is you can create folders and sub-folders and organize things much easier. I have more than a hundred of
bookmarks to this forum on my Firefox bookmark toolbar.

The fan control in RH is NOT the control that handles the PEEK fan. The fan control in RH is for the _layer_ fan. The M command listed in the manual should start and stop the PEEK fan.

g.

geneb wrote:The fan control in RH is NOT the control that handles the PEEK fan. The fan control in RH is for the _layer_ fan. The M command listed in the manual should start and stop the PEEK fan.

g.

Ahh, thanks, GeneB! I obviously haven't read far enough ahead in the manual to see that or I skipped over it like the emergency abort instructions . And here I keep telling my son, "You have to read the instructions, not just look at the pictures like Legos"

I'll move the wires back for the peek fan, then. Thanks for pointing out my mistake!

dpmacri wrote:

geneb wrote:The fan control in RH is NOT the control that handles the PEEK fan. The fan control in RH is for the _layer_ fan. The M command listed in the manual should start and stop the PEEK fan.

g.

Ahh, thanks, GeneB! I obviously haven't read far enough ahead in the manual to see that or I skipped over it like the emergency abort instructions . And here I keep telling my son, "You have to read the instructions, not just look at the pictures like Legos"

I'll move the wires back for the peek fan, then. Thanks for pointing out my mistake!

Well, RTFM is certainly good advice here! I moved the wires back to the Fan 1 location and searched the manual to find the "M42 P6 S255" command and lo and behold it works

Now that the fan thing is sorted out (which, FYI, when I started looking at it I realized that I had the fan in backwards -- it was blowing out instead of in ), I moved on to calibration.

Calibration of the hot-end and Heated bed seemed to go smoothly. I'm still not 100% certain how to use a Digital meter with a thermocouple (i.e. should the temperature I read from the thermocouple match what the LCD/RH reports that the hot-end temperature really is? Right now the meter is 10 C or more lower depending on where I end up getting the thermocouple probe to sit. Using an infrared thermometer on the heated bed reports pretty much the same temperature as the LCD/RH, give or take 1C.

So, per the manual, I heated the hot-end and bed up to temp (190C and 55C, respectively) and began the Z calibration. Once I got a number (360.1mm), I did G28 and then G0 Z5 F3500, and then G0 Z0 F3500. And the end hit the bed hard! So I did the calibration again and ended up taking another 0.4mm off the height (final height of 359.7mm).

For anyone reading, here's my question: Do I have some slop somewhere that would cause this variation (e.g. are my belts not tight enough)?

If you made no other changes, then depending where your endstop screw makes contact with your microswitch at the top, you can get inconsistant zero positioning.

lordbinky wrote:If you made no other changes, then depending where your endstop screw makes contact with your microswitch at the top, you can get inconsistant zero positioning.

What should they look like? Here are pictures (sorry the Z is blurry -- hard to take these closeups ).

I went ahead and moved my end stop switches to the middle 2 screws where they mount. Now the end stop screws hit the switches right where the actual button is rather than out on the end of the lever. Now my height calibration seems to have stayed correct even after a cooling/reheating cycle.

I think I may have also made a mistake the first time around. Last time, I had issued G28 *before* I changed the EEPROM/Printer Settings values. I think that may have caused the printer to think it was at a different height.

Anyway, I'll report back if I still have height problems, but thanks for the help!

That bump threw mine off too so I moved it back one hole so it makes contact with the flat part of the microswitch arm, it isn't quite the button itself but it was enough to fix consistency problems for me. Enough so that I stalled my plans to move to magnetic endstops.

lordbinky wrote:That bump threw mine off too so I moved it back one hole so it makes contact with the flat part of the microswitch arm, it isn't quite the button itself but it was enough to fix consistency problems for me. Enough so that I stalled my plans to move to magnetic endstops.

Good to know! Thanks, LordBinky!

dpmacri wrote:

lordbinky wrote:That bump threw mine off too so I moved it back one hole so it makes contact with the flat part of the microswitch arm, it isn't quite the button itself but it was enough to fix consistency problems for me. Enough so that I stalled my plans to move to magnetic endstops.

Good to know! Thanks, LordBinky!

Actually, it just occurred to me that a more "ideal" switch for this usage would have the arm reversed such that the screw hits near the hinge and the button is out on the end of the lever. That way a smaller motion in the movement of the carriage would trigger a larger motion on the button

lol I had went through that same thought process.

Whoot! I'm officially a "Maker" I got everything calibrated from the manual and then printed the calibration cube. This is with SeeMeCNC Blue PLA. Here are the prints with the piece still on the bed.
And then, after I printed, I realized I had threaded the filament wrong (I was going through the center hole in the top platform instead of the little hole under the spool holder). So I figured, "I'll just retract it all out quickly" ... bad idea It jammed in the EZStruder and I couldn't get it out without disassembling the whole thing and sticking a 1/16" drill bit down there. While I was disassembling the EZStruder, the springy-thing popped out and I thought I heard something else hit the floor. As I was putting it back together, I found a little pin that's ~12mm long, but I can't for the life of me figure out where it could go. The EZStruder drawings and STL files don't show any pin, so perhaps it's just some random other thing strewn on my floor


Anyway, I'm super excited that my first print came out fairly decent. Any suggestions on what needs to be tweaked to get nicer layers after the first few would be appreciated. The bridges certainly had some problems with drooping filament (temperature too high?).

Your temperature may be a little high but you may also add a fan that cools the part as it is being printed.
Many users just use a 40 or 80mm or so fan and place it on the base so that the air blows on the part. I would
connect it to a connector so that it can be removed. The connector would be controlled from a manual switch
that goes to the power supply. You will read about such fans many times as you scan through the forum topics.
Two good fan topics are listed here:
http://forum.seemecnc.com/viewtopic.php?f=37&t=1584

http://forum.seemecnc.com/viewtopic.php?t=1201&p=5781

Eaglezsoar wrote:Your temperature may be a little high but you may also add a fan that cools the part as it is being printed.
Many users just use a 40 or 80mm or so fan and place it on the base so that the air blows on the part. I would
connect it to a connector so that it can be removed. The connector would be controlled from a manual switch
that goes to the power supply. You will read about such fans many times as you scan through the forum topics.
Two good fan topics are listed here:
http://forum.seemecnc.com/viewtopic.php?f=37&t=1584

http://forum.seemecnc.com/viewtopic.php?t=1201&p=5781

Thanks for the reminder and the links! I've read so much over the last couple weeks that I keep forgetting about all of these tips I certainly appreciate the help I've been given so far!