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I recently made a video about my 3d printer. The a net, a 8 It’s a hundred and sixty dollar kit that requires you to put it all together after building and using the printer. I told you whether or not I felt like this. Particular printer was worth buying. If you haven’t seen that video, you can check it out by clicking on the card in the upper right hand corner in that video. I discussed how once you get this kit together. It works just well enough to start printing upgrade parts for itself. I got a whole bunch of comments asking me to make a follow-up video describing what kind of modifications and upgrades. I made to my printer. The biggest problem I had was levelling the bed. I really didn’t like the screw and Wingnut solution that comes stock on the machine. The bed and the support bracket are both threaded, which makes it very difficult to adjust. I found that with this two point contact system. My bed would warp and be impossible to get level. Also, you have to move the extruder out of the way to adjust the screws. I found this thumb wheel upgrade on Thingiverse and printed it out. This upgrade requires drilling out the screw tabs on the support bracket. That way there’s only one point where the screw makes contact once. I did this! I saw a huge difference and it was much easier to get a level surface while I had the build plate off. I decided to flip over the eight shape mounting bracket. This allows the Y-axi’s belt to remain parallel as it travels back and forth. I also printed out and installed a really cool action camera mount so that I can fill my prints while they’re in progress, the next modification that I did was to find a better way to add tension to the X and Y-axi’s belts again. Thingiverse was full of great solutions. Ready to print? I chose this screw tensioner for the y-axis and installed it on my machine for the X Axis. I found this belt. Tensioner not only does it provide a way to tension the belt, but it also has slots to hold the ends of the belt. I will include links for all of these parts in the description. A huge thanks goes out to all the contributors on Thingiverse who post their designs the last modification I did to improve print quality was to add some gussets to help with the z-axis rigidity. I honestly don’t think this one is really necessary. There aren’t really any forces being applied between the extruder and the workpiece that means an extremely rigid frame isn’t as important once I figured out how to level the bed and add tension to the drive belts. I wanted to print an enclosure for the power supply and add an IEC connector. I got this one on ebay for about three bucks. It has a place for a 10 amp fuse as well as a switch that makes turning on and off the printer really easy. I wired up the connector and attached it to the power supply. Having a fuse and a switch makes me feel a lot better about leaving this printer alone for long prints. I found lots of files on Thingiverse for power supply enclosures. But none that I liked a whole lot. I settled on this one. I wanted to print it upright, which required some supports. This was the first time. I tried printing something with supports and I learned a lot. The print took twice as long and used twice the amount of filament. I weighed the print before and after removing the support material 56 grams before and 28 grams After pretty crazy, right, it was also really difficult to remove the excess filament. I need to learn how to adjust the support settings so that it doesn’t use so much material. At this point? My new printer was running so much smoother and safer than before. The only upgrades that were left are more cosmetic. I wanted to add a drag chain to the x-axi’s to get rid of that huge mess of wires, drooping over the top of the printer. I see a lot of videos of people printing their own drag chain, which is totally an option for how cheap. This stuff is online. I chose to just buy one meter of it, which cost me about $4 and I only used about half a meter for this project. I designed a bracket in fusion 360 that mounts to the left Z-axi’s motor. This bracket was the first thing that I actually modeled and then printed out on my machine. Let me tell you how satisfying it is to go from needing something to modeling it in software, then printing out a physical. Copy all in an hour -. This is why this tool has become so popular. I got a few comments, saying that the AAA needs external MOSFETs for the extruder and the heated bed from what I can tell. There are a couple reasons for this upgrade. I guess on an older version of the board, the connectors they used for the hot bed, and extruder weren’t rated for the high amounts of current needed to drive the heating elements. They’ve since changed the connectors to ones that are properly rated. I guess the other concern is that the onboard MOSFETs were getting hot for some people, which would indicate that they were either under sized or didn’t have proper thermal dissipation. I was curious about what Mosfet they were using on the a8 board. So I did a quick search. I found this schematic That shows the IRL r78 43 If you look up the datasheet for this part, you’ll see that these are rated at 161 amps at room temperature. Did we just find the holy Grail of MOSFETs? This seems way too good to be true. If you scroll down to the end of the datasheet, you’ll read that. The calculated continuous current is based on maximum allowable. Junction temperature package limitation, current is 30 amps. What this means is that the mosfet could run higher theoretical values of current, but the physical plastic package limits the amount of current to 30 amps, which sounds way more realistic. That’s still pretty respectable for a MOSFET that size. I let this printer run for about 8 hours just to see how hot the MOSFETs would get when I went to touch them. They were actually cool to the touch that being said. I don’t think I’m going to add external MOSFETs to my printer that about wraps up this video if you haven’t seen some of my other project videos. I’ll put a couple of them right here for you to check out. I make a lot of project videos on this chain. If that’s something you’re interested in, you should click the subscribe button and Youtube will start recommending. You more videos like this. Thanks for watching, and I’ll see you next time [Music]!