I’ll start off with a recent one. I forgot to connect the hotend cooling fan when remounting the hotend. After a while the printer jammed and the whole toolhead got so hot that it started to melt. The brass inserts were coming out of their sockets and the hotend stood at an angle instead of straight down.
I also noticed that the “teflon” tube connecting the extruder to the hotend was not in fact teflon. The slowly melting ABS was blowing a bubble in that tube and it was clearly starting to melt.
It was quite a pain in the ass to fix as I did not have a second toolhead nor a second 3D printer to print a new one so I had to fix the extruder/hotend in place using 2-part glue hoping that the printer lasts long enough to print a new toolhead.
I should probably have either a thermal fuse or a smart filament sensor that notices jams as well. When your hotend cooling fan fails, or the operator forgets to connect it, the filament will jam in the heatbreak and if it goes long enough the whole hotend will be plastic-meltingly hot. A jam sensor should see it before the toolhead starts to melt.
I had a long print job in ABS running overnight. At some point the part detached from the bed. While the amount of spaghetti was dissapointing, the massive blob of solid ABS covering the print head was way worse. I had to cut of the majority until i could remove all non-metal parts. Then i melted the rest of in the oven.
I literally just had this happen last week but with PLA not ABS (thankfully)… I got a lot of it off and removed the toolhead (Snap Maker U1) but I haven’t had the motivation to get the blob completely off yet.
I thought my touch sensor for bed leveling was a bit of loose filament and I pulled it off. I had to replace the whole extruder. This was on an artillery sidewinder.
Printing CF-PETG on glass. It becomes one with the buildplate.
I’ve heard that said about PETG in general before. Personally I never had any issues though. Is it worse when printing CF-PETG?
Think of one and I’ve done it.
I started 3D printing…. Now I have 6 printers, a cnc and a laser engraver that also does cmyk printing
How does one buy a CNC? Asking for… er… a friend.
I bought both my laser cutter and cnc machine from alibaba. The people on there are genuinely very friendly, know their stuff and can help you select the right machine, any addons you need and logistics. They could only ship it to a port near me on a shared container. From there I needed to handle logistics. Now a normal person can’t just pick stuff up from a port (plus the size and weight would require something larger than I can drive), so I found a local logistics company to pick it up, handle the paperwork and deliver it to me.
Shipping took a while (slow boat, shared container) and setting the machine up was a bit of work. It was packaged very well, but getting it all cleaned up and assembled was a lot of work, then aligning and actually learning to work with it was hard as well. One of the drivers was faulty and they shipped a new one from China by plane which arrived in a few days, free of charge. They were very helpful throughout the process and after buying the laser cutter, I bought the cnc through them as well.
The people I dealt with were more like middle man, not the actual people making the machine. But they were very knowledgeable, being able to tell me details and give advice. This was about 15 years ago now, so they weren’t just using AI. Both machines were around $15,000 and comparable in specs and functionality to a $30,000 machine bought locally. I still use the laser all the time, recently upgraded the brain so I could move away from the ancient Windows XP software I ran in a VM on a Linux laptop I have beside it. Unfortunately I had to sell the cnc because of the divorce from my first wife, but am thinking about getting another one.
If you have some money to spend and are looking for a deal, alibaba is the place.
Do you know if thats just for medium to large machines?
Kinda my dream to get some smaller ones to build a small printer/CNC farm
The smaller ones are usually hobby/self built. There is nowadays something like Carvera, but those seem like a lot of hassle and expense for not a lot of functionality.
In my opinion there’s no such thing as a small CNC. I have a tiny one 40x30cm working volume, I use it to create PCBs from blank copper coated plates. It’s better than what I used to do with laserprinted resists and chemical etches. But these days ordering PCBs from one of those online fabs is fast and better quality, cheap as well. I can’t get the blank copper coated plates for cheap anymore, since copper is so expensive. But small CNCs often lack the power and speed to be useful and the limited working space is a big downside as well. So when I bought one, I went big, with a lot of power, speed and working surface.
Also don’t snooze on the dust extraction required, all the material a CNC or laser removes gets turned into gas and dust particles. You need well and proper dust extraction and filtering. Especially if you do soft woods and stuff like glued panels like mdf or plywood. The glue gets in the air and rains down everywhere. This causes dust to cake up and be hard to clean. It can ruin the machine and make a mess of your workspace. It’s also very unhealthy to breathe.
People doing 3D printing forget about this as well. Sanding plastics or using materials with carbon or glass inside. The dust that comes off of that isn’t good, so proper dust protection and extraction is a must.
You can make one if you have a 3D printer and some linear rails. I have a somewhat steady supply of CNC parts through my job and have designed a CNC machine around that.
Wow nice!
I’m have this https://www.sainsmart.com/products/cubiko.
But it’s very been eyeing some bigger machines
scrape the pei bed with metal.
This isn’t my hobby printer, but I once was trying to diagnose a filament feed issue with one of the Stratasys printers I run at work. This particular machine was always touchy about filament change overs (its a 4-bay F-370) and it of course failed when changing from empty spool 1 to half full spool 2. I tried remotely re-trying the filament load but it just kept complaining, so I went out and tried to manually feed the filament multiple times
It took me like 30 minutes of this to realize the feed tube had just come undone from the back of the spool drawer and I had fed 50 meters of filament into a huge tangle under the machine…
I fucking always forget to recalculate normals after intersecting shapes.
"Alright looks good, export, import into slicer. Aaaaaand the entire scene got exported…
Ok export, selection only, import into slicer. And half the walls are missing.
maybe I should just learn cad"
Why learn cad when I can just keep adding plugins to Blender until it crashes?
I tried to do an ABS print at PLA temperature once. That sure didn’t work. Vise-versa is also an interesting time, especially if you have the lid on the enclosure shut. If you think you’ve ever seen heat creep, try having PLA in the extruder but running it at 260°C and the chamber heater on. The resultant jam required stripping the entire extruder head down to its individual components and prying it apart in the process, but I put it all back together and it still works. I didn’t even have any screws left over by the time I was done.
Like all Qidi X-Max 3 owners will eventually do at some point, I also once homed my machine without the steel build plate installed. This causes the machine to helpfully drill the nozzle straight into the soft magnetic surface between it and the heater plate. I shaved the high points off of the crater with a straight razor and continued to run that plate without any problems for several months after that. You’d never notice the difference, despite the hole in it.
I didn’t even have any screws left over by the time I was done.
Lies! Haha
CrealityPrint resets the prime tower every time I change anything. I’ve had so so many plates of prints with a model or two fused with the prime tower because I forget to move it.
Forgetting to reattach the PTFE tube and feeding endless filament into open air.
Printing directly onto the magnet, with no plate installed—weirdly enough, the print came out okay-ish, with only the bottom layer not great.
Using metal grease instead of thermal grease when installing a nozzle—pretty sure that’s what eventually lead to my hotend failing.
Not setting purge volumes correctly, and ruining full plates with massive colour bleed.
Thinking I can skip the prime tower, and that it will save filament (it doesn’t), since it purges anyway. Then not even noticing how badly filament bubbles without priming.
Not realizing that the printer purges multiple poops, so seeing so many clean colour poops means I’m purging too much. (I wasn’t.)
Not noticing that a 2-colour print was alternating colours in the infill, and that’s why the colours were always muddy, and that increasing purge volumes was just wasting more filament.
Never calibrating a filament, or even changing settings to match manufacturer settings, leading to printing fast PLA way too cold, and turning to spaghetti from poor interlayer/bedplate adhesion.
Not removing a colour-change-by-layer when scaling a model, leading to an entire plate with the wrong colours. (The top layer on a flat print, of course…)
Selecting the wrong filament colours when sending a print.
… I could go on. At length.
They say you learn the most from failure, so I’m pretty sure that makes me an expert.
Forgot I’d changed the filament from PETG to PLA or vice versa. I did it twice, and not since. Took me hours to clear.
Old one I’ve told before, not moving to a fixed hotend as soon as possible (v6 style hotends the mk3s uses for example, really easy to mess up) have absolutely accidentally loosed the block during a nozzle change, petg was leaking out of the top super slowly, only realised the issue once the blob started pushing the sock off.
Kept that hotend around for a while as a display piece, was a total write off. That also was the event that made me start keeping spares on hand, why I have my printers more or less part compatible for consumables (always keep a few extra heaters and rtds/thermistors around, do also have at least one extra hotend around).
Walking away too soon. 😂
I went from a .4mm nozzle to a .2mm nozzle. When I went back the other way, I forgot to update the nozzle profile and despite cura knowing the line width was .4mm, it extruded as if it was .2mm forcing severe underextrusion until I figured it out…weeks of failed prints later. I rebuilt the printer like 3 times assuming it was physical.
When I got my first PEI bed and was manually leveling, I had the nozzle hot and left it there for too long as I was doing something else and had a big burn mark. Thankfully only had to replace the PEI sheet, but I learned by lesson.
