3Drag Velleman K8200 new y-axis rods - 10mm instead of 8mm

thingiverse

I've been working tirelessly on my printer for an extended period and firmly believe that the 8mm rods on the y-axis are simply too flexible. Therefore, I embarked on replacing them with 10mm rods, a decision motivated by the notion that this relatively small change of 2mm to 10mm rod should result in roughly doubled stiffness due to its cubic relationship with diameter. One could reasonably argue that an increased mass will now be circulating around this modified system, which is true. By making this switch, there's a noticeable rise in mass by approximately 56.25%, translating to a significant addition of about 124 grams overall. Should you opt for printing on glass, this augmentation would equate to adding roughly a millimeter thickness to your panes. Simply put, decreasing the thickness from three millimeters to two is all it takes to strike an acceptable balance again. During my personal project development, I've also replaced the original bearings with igus DryLin linear bearings, a move aimed at not only reducing their weight but also generating far less noise overall. I encourage you to indulge in this modification and feel free to use my approach as your inspiration. This alteration's foundation can be found on http://www.thingiverse.com/thing:203292 Update 31.5.2015 Upon integrating these upgrades into my machine, I observed that the screws could easily get lodged within the bearings if you opt not to employ either shortened M5 screws or place two additional washers in between - a scenario no one desires, to say the least. Update 13.6.2015 An enhancement was subsequently discovered for the width of the X-axis: its slight augmentation is advisable, given it mitigates bed movement along the Z-axis resulting from bearing tolerances. Update 19.6.2015 When building this piece, a worthwhile recommendation would be to opt for an infill level ranging between 30% and 35%. Not only does this render your printed product stronger but also imbues it with enhanced durability. Update 30.9.2016 Later on, I resolved the issue of steel rods by swapping them out for aluminum ones. Hardened aluminium-based alternatives do indeed exist, but please avoid combining these aluminium bars with typical ball bearings unless using an igus bearing. By making this shift to IGUS type linear bearings, you can reduce approximately 270 grams off the tray weight - more than enough balance gained thanks to the added mass brought about by swapping from a diameter of 8mm to one measuring 10 millimeters. This still takes full advantage of increased rod stiffness! Update 11.7.2017 In an attempt to further perfect the alignment achieved via these linear bearings, I opted for a different course: allowing everything involved to be fully adjustable as needed. By taking this extra step and addressing my tolerance concerns, you will now witness no more hinting of play at all throughout every part, significantly affecting output print quality in general.