was to upgrade the Ultimaker 2 for better and faster prints. Therefore I exchanged several parts from the extruder to the hotend. In this post you will read about my project, which parts of the printer I changed, which designs I used, altered and printed. I will also show the differences between used parts and the new replacements to determine the wear.
In the end the printer will be more efficient due to faster prints, less failed prints, shorter heat up times, less temperature losses and a cooler main board.
Since 2014 I got my Ultimaker 2 and we went through a hole lot of prints. As a student I printed many of my designed parts for the electrical racecar of the formula student team I participated. But with the time the prints did get worse. From the beginning I was looking for a good feeder. After the launch of the Ultimaker 2 there were a lot of good alternative feeder designs e.g. IRoberts which has been downloaded up to now 15.000 times. I tried a lot self printed feeders with better and worse results as the original feeder.
I have been stuck now with the Bondetech QR Extruder, which is a bit expensive, but you get a really reliable feeder. After half a year of use I can say that it is reliable and my problem of underextrusion are vanished.
Solex V3 Hotend
bowden tube attachment
3D Solex V3
First new component ist the hotend from 3D Solex. The design is really similar to the Olsson Block. The difference you see is the surface finish.
The new nozzles have a different coating and a longer thread. With the old Olsson Block I had some problems with the thread. Some filament came out of it and accumulated in the fan shroud.
I also replaced the teflon piece with an differnet one from 3D Solex.
For a better movability of the temperature sensor and the heat cartridge I put some copper paste on them, before I placed them into the hotend.
replacing the Olsson Block with the Solex V3
When I tried to loosen the Olsson Block I sensed a lot of resistance. After an hour of trying every possible way to loosen the connection between Olsson Block and the coupler with teflon lubricant the coupler broke. Good thing about that I could dissemble the printhead, but I had to replace the coupler. After searching in the forums I recognised that I was not alone with the problem and the aftermarket had a solution with an even better steel coupler.
After I took everything apart I found the problem. The ptfe part coalesced with the steel coupler. The solution for this problem is a small black ring which keeps the two parts separated from each other. Also some copper paste between the steel coupler and the hotend will help later dissembling.
The Bondtech extruder is based on an simple very good construction. Two knurled gears from each side force the filament through the bowden tube. Advantages are less deformation, more torque due to a bigger motor and the gears and a better bowden connector.
I had a lot of problems with underextrusion bevor I bought this extruder. With the Bondtech all problems related to underextrusion vanished. If you have some money left I can recommend this extruder.
First things you should print after replacing the old extruder with the Bondtech are the attachment parts. It happened to a lot of people in the forums, like me, the delivered ABS parts broke after 40 hours print time. My advice would be to print it with some high durable PLA.
adding new fans and replace old ones
One thing I don´t like about the design of the printhead is the hotend cooling fan on the backside. It is really noisy and the airflow is suboptimal. Therefore Christopher Bray designed a distance part. I also swapped the cooling fan for an 25x25x10mm fan (Amazon). With the distance part and the slightly bigger fan the cable management on the backside of the printer had to be reorganised. Thats why I modified the bottom printer head part with cable holes on the backside, the design is on youmagine.
Due to the load with the new heat cartridge I added a rotational fan for the board designed by Erick. This adds some “new” noise to the printer, like a PC fan. But it´s not as noisy as the original heater cooling fan.
For the fan shroud I found a design for centrifugal fans from gudo. Centrifugal fans produce more airflow by the same poweruse furthermore the airflow at the printhead can be optimised.
optimizing the filament path
I replaced the bowden tube with a new one with 4mm inner diameter. On top of the print head I placed a different tube connector with a fitting designed by Abel. I altered the abutment too use it with my fittings which got a 1/4″ thread.
I added a Tunell sensor to my setup. After some print hours a small important part broke. So I redesigned the base for the sensor board and added threads for the fitting so it will fit nicely in the filament path. There are two options for using the sensor. First by using a different firmware for the printer, good described in the forums. Second in combination with an raspberry pi and Octoprint. Due to I´m still experimenting with the settings I will do a little guide in the next future.
Ultimaker 2 acrylic cover
To stabilise the temperatures inside the printer I decided to commission a cover from a local acrylic glass workshop. The source files are from a design from Imaginables Australia. I modified it quite a bit for my purpose. With the cover the printer is quieter, protected from any wind and it looks really nice.
Because the new cover sits right on top of the printer I had to redesign my side spool mount to a smaller and better one. You can get it from youmagine. The side mount of the spool works really good for me. It improves the filament path to the Tunnel sensor and the feeder.