We Are Learning 3D Printing Through Our Personal Experience…
If you remember a while ago we’ve had a weird issue with the filament guide tube on our MakerBot Replicator 2 3D printer. Since then we’ve replaced the teflon filament guide tube with a new one and the device was working normally again, but we also started experimenting with different ideas about optimizing the spool holder position in order to eliminate completely the guide tube as a means to avoid possible issue in the future. The general idea was to develop an overhead spool holder that would attach to the top of the 3D printer and sit on one of the sides of the 3D printer. While working on this idea designing a simple and effective solution we’ve come to another interesting and much easier solution that tends to work surprisingly well in out experience and we’ve decided to share our findings with you to help you get less issues if you are using a Replicator 2. It requires you to reposition the filament spool holder and to print two small parts that will be used to guide the filament to the extruder. All in all you can do this simple modification is no time at all.
First you need to remove the filament spool holder from the standard position at the back of the printer. You need to attach it to the back plastic panel of the 3D printer, surprisingly it was a perfect fit and the result is really good as it brings the filament spool at a perfect height that would allow you to avoid using a filament guide tube. Furthermore you can use two spool holders, one on each side of the back of the printer making it easier to switch the filament as well as making it compatible with the Replicator 2X if you are not using the top cover. This does not require any modification to the printer itself whatsoever and works really well for the moment based on our own experience using the modification.
Next you need to print two of these filament guide adapters that we’ve posted on Thingiverse and attach them to the cables that go to the extruder of the printer. They are with a clip on design, so they are easy to attache and not so easy to detach from the sleeved cables and then you just need to pass the filament through the two holes of the printed guides and insert it in the extruder. As we’ve said already it is really easy and works very well. After we’ve done this modification/upgrade to our MakerBot Replicator 2 we’ve seen a decrease of the problems with failed prints associated to filament jams when compared to the standard design with the spool down at the back and using the PTFE guide tube for the filament.
If you do try this please report how it works for you and if you are seeing any difference on your end. This modification is originally designed for MakerBot Replicator 2 3D printers, but it will most likely work on other models that are similar in design to the Replicator 2.
The MakerBot Replicator 2 3D printers are not among the most affordable ones and yet they do not have features in their build that more affordable devices on the market have by default. One such thing is the fact that the Replicator 2 3D printers rely on bushings instead of linear bearings for their moving parts along the three axes. While the use of bushings does work pretty well in the long term it could lead to reliability issues, so we have decided to try replacing them with linear bearings – something that needed some research and has turned out a not so easy task to do. What you should be aware of is that the replacement of the bushings with linear bearings should not lead to improvements in the quality you are getting, unless of course if you’ve already had some issues with the bushings.
The total number of bushings that you need to replace on the MakerBot Replicator 2 with linear bearings is 8 + 4 or 12 in total – there are 4 on the extruder head, and 2 on each side along with 4 more for the build table that moves along the Z axis. We are saying 8 + 4, because all of the bushings and respectively the linear bearings that you will need are different in size. The bushings for the Z axis or the build plate are actually with a bit larger size and we are still having trouble finding suitable linear bearings to replace them, so we actually changed only the 8 other bushings.
To replace the bushings that are used for the X and Y axis movement you will need 8 linear bearings that are marked as LM8SUU that are with a size of 8x15x17 mm (the actually used bushings are 1 mm shorter at 8x15x16 mm, but that is not a problem). The LM8SUU are the short version of the LM8UU bearings that will simply not fit in the MakerBot Replicator 2 as they are too big, so be careful that you choose the right model. The two bushings on the back for the build plate movement along the Z axis are with larger inside diameter, their size is 10x15x16, so the LM8SUU linear bearings won’t fit there. Unfortunately we are still not able to find a linear bearing with larger inner diameter and the same outside specifications (10x15x16 mm or 10x15x17 mm) as the LM8SUU to replace the two bushings along the Z axis, so we’ve settled only with installing linear bearings along the other two axes.
The disassembly of the X and Y axis movement mechanism is not that hard and you can repetitively quickly replace the bushings with bearings (you detach the whole mechanism from the top of the printer), unlike the more complex and hard to do disassembly of the moving mechanism along the Z axis. But as we’ve said the different bushings used along the Z axis and the act that we were not able to find suitable linear bearings to replace them, so there is no need to disassemble anything there anyway. One interesting things that we have noticed is that the bushings used for the extruder head were a bit different 2+2 in terms of visual appearance, but apparently also in terms of tolerance. The same goes for the bushings on the two sides, they are again 2+2 in terms of visual difference and tolerance, meaning that the ones with a bit larger tolerance move more freely as compared to the others. We have not noticed any difference in the behavior of the Replicator 2 after replacing them all with the same type of linear bearings, so we are not sure if there is a reason to use slightly different bushings and mixing them.
Time for another upgrade to our MakerBot Replicator 2 3D printer, this time we have decided to install aluminum arm stiffeners in order to help eliminate sagging of the build plate and reduce the lateral build plate vibration and movement during printing. The upgrade parts we are installing are the Aluminum Arm Stiffeners from Performance 3-d. The installation kit we got is designed to fit multiple 3D printers and it includes pretty much all things to mount it including screws and a drilling tool that is partly 3D printed. These Aluminum Arm Stiffeners are designed to be fitted as an upgrade on Makerbot Replicator 1, Replicator 2, Replicator 2X, Flashforge Creator, and Wanhao Duplicator 4, Duplicator 4X.
The arm stiffeners are relatively easy to install and it should not take a lot of time, then you need to spend some time tweaking things up before finally tightening them – try moving the build platform up and down over the Z axis to make sure that everything is fine. The results after installing the upgrade – less problems with failed or not that good looking 3D prints as with other upgrades that we have already installed, but still we do still have some issues from time to time. In general however after installing each new upgrade to our 3D printer we are getting less and less problems after that, so there is definitely an improvement, either small or big.