Jason - would you be willing to share the details of how you did that? I’m a total noob at this, and trying to help an elementary school with their Mini. They just trashed their PEI sheet when the nozzle dug into the sheet and melted a hole in it. a descrition suitable for a beginner would be greatly appreciated.
I’m not sure if their accident is related or not, but I suspect something caused a leveling issue. However, they had not touched the machine since it happened, and the disks and nozzle all looked very clean… at least my eyes.
BTW… do you or anyone else know if a wipe-down with isopropyl alcohol is enough to remove the suspected PLA film from the washers and nozzle, or do we need to get more aggressive (scotch brite or ??). We see nothing, but if there’s a chance there is something there, we want to get rid of it. We may switch to HIPS filament, if that has less of a problem. We were given a roll of PLA which we thought we’d try to use up first.
Easiest method would be to download the .hex file, and use Cura to update the firmware. From “Menu” choose “Machine” and then “Install Custom Firmware”. Navigate to the downloaded hex file and select it. It will then upload to the Mini. If it doesn’t work for you, you can go through same menu sequence but choose “Install Default Firmware” instead to put things back to normal.
On filament, I would suggest PETG. I had a nasty allergic reaction to HIPS fumes and while HIPS doesn’t bother most people, maybe it would be better to try something else with kids. PETG isn’t specifically foodsafe, but it is rooted in foodsafe plastic – two liter bottles and all that sort of packaging. It also prints very reliably and I have nowhere near the leveling issues as I do when using PLA.
Thanks, Hemocyanin. I was not going to start them off with PLA, but the other parent who is somewhat involved (and who is the one who knows something about 3D printers) had a spare roll of 3mm (she mistakenly ordered it, when her own printer is set up for 1.75mm). When you are on a school budget, you tend to take what is given to you. At the time, that was the only filament we have, since no one seems to sell it locally, and the stuff I had ordered had not come in yet. We have a few rolls of HIPS to work through, then we’ll try some of the PETG as you suggested. (If someone has a reaction to it as you did, we we may make the switch sooner.)
I notice he has posted a newer version a few days ago: v1.1-RC3.2 than what is linked to in the thread you suggested. A question for you: will this work on a stock Mini? I see a lot of reference in the change history to LCD screens, which we don’t have installed.
I’m wondering if we should stay with the stock Lulzbot firmware until the warranty runs out - especially since we’ve already had a problem where things went haywire, and the nozzle melted a hole in our PEI.
Not familiar with firmware programming, but I thought I remembered seeing something that they had incorporated a “pause” feature so someone could build in a pause during the printing of an object (to allow for switching filaments or ??). How do they resume after that pause?
Personally, I would not have a problem adding a switch, but I used to do a lot of messing around with electronics, so soldering in a few connections doesn’t bother me. My only hesitation would be wanting to wait until the warranty ran out first.
I hadn’t realized there was a newer version published, so there is no reason for my link to the older version except that I didn’t know there was a newer one. That said, before I posted the instruction above, I tried it out on my Mini and it worked great (printed out a rocktopus) although I think for the same speed values, it runs a bit faster than the default version. That’s a subjective impression though and may be wrong. Anyway, the part printed out fine – no issues.
I should say though, that I have the miniRambo version 1.3a in my LBMini because I blew out an endstop controller on the original board by using bronze wool to clean the nozzle while the machine was plugged in (word to the wise, don’t do that! ). I was too impatient to send it in for a repair and so I replaced the old board myself with the newer version, which interestingly, has the header pins for the display and I actually have one kicking around. Maybe I’ll try hooking it up.
I don’t think so but I don’t speak from actual knowledge. I seem to recall a thread recently where somebody complained that the new version was not being used and someone else pointed out that from a manufacturing perspective, it is good to keep components the same through the entire run of each version. So I’m guessing it still comes with the 1.3 version.
Just found the “Quality Assurance Record” that came with the Mini. It’s got the Mini-Rambo1.1b electronics. The testing was completed on Oct 14, 2015, so apparently by that date they were still using the 1.1b board.
I have been running the new firmware for a few weeks now and I have not seen any issues.
I’m thinking about using the Z stop for the continue feature when auto leveling fails. You would just trip the Z-stop flag to have it retry the homing after a failure.
A big consideration for an elementary school. The teacher is very tech-savvy, but not a whole lot of experience with 3D printers. I’m sure the kids will pick it up faster than either of us.
). I was too impatient to send it in for a repair and so I replaced the old board myself with the newer version, which interestingly, has the header pins for the display and I actually have one kicking around. Maybe I’ll try hooking it up.