I've been using a Makergear hotend (http://www.makergear.com/products/groovemounts) with my old-fashioned MK4 plastruder. The hotend was the only thing that let my MK4 plastruder become a no-fail plastruder. However, there are always things to improve with a Makerbot. One of these things is what I call "Nozzle Wobble". Nozzle Wobble is when the end of a nozzle has the ability to move some fraction of a millimeter because it is not well anchored to the plastruder. On the MK4, which had two screw anchor points on the body, there can be lots of wobble. Additionally, these screws put lots of downward force against the acrylic, and can crack the acrylic. I've made a small kit of 4 pieces that lets you use a MakerGear GrooveMount hotend with the MK4 plastruder and have no wobble. I am sure that the later plastruders (MK5, MK6) don't have as big of issues as the MK4 did. However, I am cheap and don't want to upgrade my whole plastruder. This project isn't the most practical, as you cannot easily remove your hotend with it and it is only applicable to people with both GrooveMounts and MK4 plastruders. The major thing is, if you can secure your hotend tip so that it has no ability for independent movement from the MK4 or platform, your prints will definitely improve.I've posted prints from thing 1140 (http://www.thingiverse.com/thing:1140), before and after securing my hot end. The quality is improved, with thin walls lining up on each layer much better.Print the three parts (the clamp part actually has two parts).Remove the MK4 plastruder from the platform. Remove your current hotend. Remove the horizontal screws across the dinos. Remove the foot from one of the sides of the dinos.Put the clamp parts around the Groovemount barrel. Put the Left/Right Arms on either side of the clamp parts. Screw an M3x50mm screw through each of the four horizontal screws that will link all the printed parts (left/right clamps and left/right arms). Slide the arms up the sides of the dinos, and align the screw holes with the dino screw holes. Screw an M3x20mm screw through each of the holes to anchor the Groovemount holder. Reattach the dino feet. Reattach the MK4 plastruder to the platform.