"Surge" minimal frame upgrade for Anet 3D printer

thingiverse

Some time ago when I assembled my first Anet A8 printer I had huge problem to do bed levelling. I found that with tight Y belt tension the frame deforms from one side to another when bed moves. Yes I tighten my belt really hard and there is reason to do this. I looked at existing solutions to stabilize the frame but did not like any of them. The best one was AM8 but it looks more like different printer with amount of work more than required to assemble original printer. But I wanted something more simple and fast. I did some measures and put my imagination to work. Finally I came with the upgrade idea that with minimal work upgraded the printer to the really advanced printer. The result is amazing. It fully stabilizes the frame in all directions, no bending anywhere anymore. I put the video with my original printer upgraded: https://youtu.be/UvYckIBDChg The parts there are slightly different but generally all the same. After some time with happy printing with amazing quality I decided to buy another Anet printer and do the same upgrade. For the price and the outcome this is really bargain. Now I could print at really high speed with very very good quality! By the way: when I said minimal work I mean minimal work to assemble it but designing and redesigning took some time and efforts for me actually. In order to do the "SURGE" upgrade: You need to remove front and rear acrylic panels and threaded rods that hold them. Everything else reused, you even don't need to disconnect any wire. You will need two aluminium extrusion 20x20 profiles with the same length as your Y rods or couple millimetres bigger (make sure not smaller, because Y rods goes partly inside the frame). I have them 382mm long. You will need another two aluminium extrusion 20x40 profiles, one 295mm long goes at the front and another 350mm long at the back. You need to print: left and right rear mounts, left and right middle mounts, left and right front mounts, two rear legs, two front legs, three rod mounts, one special rod mount with endstop mount, motor mount and Y pulley mount. Also I recommend to use GT2 toothed idle pulley for Y belt. The motor mount looks like part of the original rear panel, you need original acrylic motor mounts to put here (one still attached to the motor + another one used as support). Also you need a lot of M5 sliding T-nuts, M5x8mm and M5x10 hex socket button head bolts with M5 washers (recommended). Need to count them later. First attach original motor acrylic mounts to the printed motor mount with original M3 screws and tighten them, then attach it to the rear 20x40 profile with M5 bolts but not tighten yet. Attach printed Y pulley mount to the front 20x40 profile with M5 bolts. Attach printed middle mounts to the 20x20 profiles (one to each) with M5 bolts but not tighten them yet (they should slide). Attach middle mounts to the printer frame at the left and right with two original M3 bolts (possible need +4mm bigger), tighten them. Attach printed rear mounts to the acrylic frame on the left and right side panels rear parts with original M3 screws and tighten them. Now attach 20x40 rear profile with the motor on it to the printed rear mounts with M5 bolts but not tighten them. Also attach 20x20 profiles to the rear 20x40 profile. Make it symmetric: measure distance between 20x20 profile at rear and at the front, the distances should be the same, slide mounts until distances match and tighten M5 bolts. Tighten all bolts left not tightened. Attach front 20x40 profile with Y pulley to the 20x20 profiles with printed left and right front mounts and M5 bolts and tighten everything. Now put bearings on the rods and put printed rod mounts onto the rods from both sides. Attach the mounts with the rods to the frame profiles with M5 bolts. The rod mount with endstop mount should be at the rear right. Attach bed base to the bearings and make sure the bed is symmetric and slide easily. Make it symmetric before tightening! The geometry of the printer will not change, the Y rods will be in the same position in space as before. The endstop will be slightly at different position and amount of freedom in Y direction will be slightly bigger but all this about millimetres. You will have amazingly stable and rigid frame.