We Are Learning 3D Printing Through Our Personal Experience…
Today was a day for another upgrade to our MakerBot Replicator 2 3D printer – replacing the stock plastic X-End gear with an aluminium one that comes with installed bearings. The stock plastic gear works well, but since it is directly in contact with a metal shaft there is a chance that the gear might wear off in time and start giving you trouble. Normally it is recommended to apply some grease from time to time to the shaft in order to help the gear to move smoothly and not to give out some nasty squeaking sounds. This is where the Aluminum Idler kit for Carl’s ALU X-End or Stock X-End from Alm Gear comes into play to address this issue and make the printer more reliable on the long run. This upgrade is for improved long term reliability and to reduce possible future issues and not to improve the quality of prints or something like that. The Aluminium Idler kit is available for $18 USD and comes with Aluminum GT2 16T gear with bearings installed as well as two steel shafts with different length (the shorter one is for the Replicator 2) as you can see on the photo above. It is designed to be used as an upgrade for MakerBot 1, 2, 2X and some clones of these 3D printers.
To replace the stock plastic gear you need to loosen the belt that moves the extruder over the X axis of the 3D printer and in order to do that you need to remove the 4 screws holding the stepper motor that moves the belt. It is relatively quick and easy to do this modification, so ti should not take you more than a few minutes to do it and get back to using the 3D printer again. Again, this is an upgrade that can save you some possible future trouble and not something that will directly result in the improvement of print quality or performance of the device. So don’t expect to see any difference immediately after you install the new gear, unless of course your old one was already causing you some issues as a result from wearing off for example, especially if you left it unmaintained and has never applied some grease to help it run smoother.
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.
We have written about the GeckoTek 3D Printer Build Plate a while ago as it was an interesting alternative to using various kinds of tapes to cover your 3D printer’s build plate. The project started on Kickstarter, but since we have missed backing it up then we have purchased a kit for our MakerBot Replicator 2 3D printer back in November last year hoping to get it in early 2015. It seems that the actual production of the build plates has suffered numerous delays and things have just stated happening in the last few days according to the updates on the Kickstarter project page. Apparently there is no chance to have a single solution that will be suitable for different kinds of 3D printers and with different materials.
Based on the information published in the latest updates apparently the current version is suitable for PLA and non-heated build platform devices, ABS and heated build platforms will probably require a bit different coating and we may actually see these available in the summer this year. GeckoTek may start shipping PLA versions of the build plates to backers that will be using them on devices that use this kind of filament only. Unfortunately this goes only for Kickstarter backers that have priority before customers like us that have purchased a kit from the official product website. What we are not happy with so far regarding the GeckoTek is that they are not sending any news and updates to actual customers that have purchased and paid up front for their product and updates are only published on their Kickstarter page.
At the moment we would not advice anyone to purchase a GeckoTek 3D printer build plate for the moment directly from the official website of the product, better wait until the company actually has fulfilled the Kickstarter orders first and starts shipping actual products to new customers. Meanwhile we are already looking for various alternatives that are already available on the market providing more durable surface for 3D printing on, good adhesion and easy removal of the printed parts. One such alternative that we are already testing is the BuildTak 3D printing surface and you can expect our first impressions from using it very soon.