MakerGear Forum

read your post, interesting, but looks very easy to mess up and run the nozzle into something it shouldn't. With new Rev. E machines the Z limit switch is in a different position (at the machine bottom).

Basically all that should happen is nozzle stays off (cold), all axis's home, then nozzle moves to right side off bed as normal. At this point the nozzle then turns on, sits there waiting to come up to temp, then does it's normal purge and the rest continues on from there the same as usual. Putting the nozzle against the bed, building pressure, blob, etc. just sounds like a broken nozzle and/or broken glass if not done exactly precise (don't see any benefit to this?)

The rev e homes to the bottom, not the top so the thing to do is probably look at the start script and take the line that moves the nozzle over to the the bed edge to do the purge and move that before the line the moves the bed up

hybridprinter wrote:if not done exactly precise

G-Code is nothing if not precise: the printer does exactly the same thing in exactly the same way, every time it starts up. In this case, it clears gunk off the nozzle at exactly the same spot and starts printing with a properly pressurized hot end.

I watch that happen and rarely pick a small blob off with tweezers, but printing is, by and large, a hands-off operation.

I've been using an all-glass platform for a bit over three years and a V4 hot end with the original nozzle for two, with a few tweaks to the G-Code along the way, so it's not a high-risk operation.

don't see any benefit to this

You'd asked about a start-up script that didn't crunch the nozzle. There's no magic, just G-Code to position the machinery at exactly the coordinates you specify.

Thank you Ed, its a very good idea you put together for the startup script, just a bit advanced for a newbie.

Please excuse my lack of gcode experience.

Not sure why the machine needs to home at all before a print?

hybridprinter wrote:Not sure why the machine needs to home at all before a print?

When the firmware starts up, it has no idea where the platform or extruder are; maybe you moved them by hand or, heck, completely rebuilt the printer. The home switches are in known positions along each axis, so the firmware can drive each motor until its switch trips, whereupon the motor is in the proper place to apply the "home" coordinate. Do that for all three axes and it's ready to print.

a bit advanced for a newbie

How you get from newbie to expert is by saying "Hey, I don't want the nozzle mashing into the platform!" and then figuring out how to make that not happen. Yeah, you'll fumble things as you go, but that's pretty much how everybody learns things: you learn more when things don't quite work.

Basically, don't be terrified that you'll wreck something: get in there and tweak it a little bit to see what happens. Worst case, you're out a few bucks, but you'll know what not to do the next time.

You should see my scrap box …

hybridprinter wrote:read your post, interesting, but looks very easy to mess up and run the nozzle into something it shouldn't. With new Rev. E machines the Z limit switch is in a different position (at the machine bottom).

Basically all that should happen is nozzle stays off (cold), all axis's home, then nozzle moves to right side off bed as normal. At this point the nozzle then turns on, sits there waiting to come up to temp, then does it's normal purge and the rest continues on from there the same as usual. Putting the nozzle against the bed, building pressure, blob, etc. just sounds like a broken nozzle and/or broken glass if not done exactly precise (don't see any benefit to this?)

Here is my start script. There is an initial wipe on the front to clear off anything that could potentially for a blob.
https://youtu.be/jp9WkVevMrs

I'm new to this forum but I just wanted to post about the BIG help getting those PETG settings were. I wish there were a way to post pictures because I took a great one comparing my old settings to the new !

Ceebee wrote:I'm new to this forum but I just wanted to post about the BIG help getting those PETG settings were. I wish there were a way to post pictures because I took a great one comparing my old settings to the new !

Posting pictures to the forum is pretty easy actually. Just click on the "Upload Attachment" tab under the reply window. (see red arrow) Click "Browse" to find the picture on your hard drive, then click add file.
Then if you want you can use the "place inline" button and it will inset the picture into your type were ever your curser was. You can do this up to five times per post if doing several pictures and type. You can also just add type to the file comment section with out using the place inline button.

Thanks.

But for some reason, I don't have that tab...

You have the X/Y Axis Movement Speed set to 12000.0 mm/min. Is this correct or did you mean 1200 mm/min? I want to make sure before I start printing.