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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.
New NinjaFlex SemiFlex 3D Filament Available
22 Jan2015
Fenner Drives, the maker of NinjaFlex a flexible 3D printer filament has announced a new variant of the NinjaFlex family, the SemiFlex 3D printer filament. Like the original NinjaFlex 3D Filament, SemiFlex material boasts flexibility, strength and reliability for your 3D printing projects, and is slightly more rigid to expand your printing possibilities. For the moment the new SemiFlex 3D printer filament is available in just 4 colors: Black, White, Blue and Red with the spool price for the standard more flexible NinjaFlex and the less flexible SemiFlex filaments being the same.
The new SemiFlex 3D filament features a consistent diameter and material properties providing reliable, high quality prints like the original NinjaFlex. It uses a patent pending technology for smooth feeding with a low friction exterior that allows smooth feed through filament guides. The filament provides high elasticity and excellent abrasion resistance, excellent build platform adhesion and bonding between layers and comes with a filament hardness of approximately 98A (50D) for SemiFlex as opposed to 85A for the NinjaFlex. The new SemiFlex 3D filament is available in both 1.75mm filament spool 0.50 kg weight and 3.00mm filament spool with a weight of 0.75 kg.
SemiFlex is best for the following types of projects:
– High level of detail
– Contain intricate parts
– High resolution text
– Unsupported vertical printing
– Shock-absorption needed
– Requires less flexibility than NinjaFlex Original 3D Filament
The SemiFlex 3D Filament Processing Guidelines recommend extruder temperature of between 210-225°C with no heated bed required for printing, though if you have and use one you might want to keep the temperature below 50°C. The recommended Print Speed is 30 mm/s, just like for printing with the original NinjaFlex filament, so prints using this material might require more time than what you would need as compared to when using standard PLA filament for example.
- In: 3D Printer Filament
- Tags: 3d printer flexible filament, Fenner Drives, flexible filament, NinjaFlex, NinjaFlex 3d printing, NinjaFlex extruder temperature, NinjaFlex print settings, NinjaFlex print speed, NinjaFlex recommended settings, NinjaFlex SemiFlex, SemiFlex, SemiFlex 3d filament, SemiFlex 3d printer filament, SemiFlex filament, SemiFlex printing settings, thermoplastic elastomer, TPE
We were looking for a while at alternatives to using various kinds of tapes to cover the build plate of a 3D printer that can provide good adhesion, easy removal and most of all to be more durable, so that we won’t have to replace it often. One such solution that we have found out about is the BuidTak 3D printing surface that is essentially a specially developed thin plastic sheet that you stick on top of your build plate. This 3D printing surface is supposed to provide an optimal printing surface for 3D objects to adhere to for the duration of a print, while allowing for a clean, easy removal of completed builds. It is heat-resistant, so that you should be able to use it for ABS printing as well if you have a 3D printer with a heated build platform and not only PLA.
A single sheet of BuildTak should be more durable than any kind of tape and the price is affordable enough if the surface proves to be durable enough for making a lot of prints before having to replace it. The surface is available in multiple pre-cut sizes including rectangle, square and circle shapes that should fit on most FFF/FDM 3D printers available and if the size you need is not available you can go for a larger one and then cut the extra. We got two sheets with size of 292×165 mm (6.5″ x 11.5″) at $12 USD per sheet, this is the size needed for the build plate of the MakerBot Replicator 2 3D printer that use use with just a bit needed to be cut at one of the sides after applying the surface to the build platform.
Sticking the BuildTak 3D printing surface to the build plate of the 3D printer is a bit tricky, it is a lot like when installing a screen protector on a mobile phone or a tablet. You need to be careful and to remove air bubbles while sticking the surface and not trying to remove them after that as it will be very hard or impossible. Our first installation was less than perfect and we’ve had a few air bubbles left, good thing that we have ordered a spare sheet. Do note that after applying the BuildTak you will need to re-level the build plate as the height of the new 3D printing surface is probably going to be a little more than that of the tape that you have used before. Make sure you level the build plate properly by doing a test print, we have found out that printing a SIM card adapter does a great job for testing the proper leveling and is quick to print and uses little filament.
After applying the BuildTak 3D printing surface we have started printing using different filaments. No problems when using PLA – the printed part sticks well and is easy to remove, not that we expected otherwise, so we have moved to other more problematic filaments. Going for ABS on our 3D printer without a heated build platform we have observed the expected warping of the base of the printed part resulting in the object not being able to adhere to the build surface for long. We have then tried Bendlay filament, something that we had trouble printing on our Replicator 2 using the 3M ScotchBlue tape – we had trouble having the material to stick no matter what settings we have tried. With the BuildTak installed however we had no trouble printing using Bendlay filament, it was sticking quite well with very minor warping that we have observed at the very edges of the test prints – something that can easily be overlooked as the prints were fine in general. Next up was the T-glase filament that we also had trouble printing with on the standard blue painters tape, however the situation was not as good as with Bendlay here. It certainly was better than with the painters tape before, but still not good enough adhesion – we may have to play some more to find the best settings for printing T-Glase on the BuildTak.
We are going to continue playing with the BuildTak 3D printing surface printing with different filaments, but so far we are already seeing better results than when using various tapes for covering the build plate. Another good thing that we have also observed when using the BuildTak surface is that the bottom of the 3D printed parts is that it is smoother to the touch and a bit better looking as compared to when using painters tape.