Attaching the Flex Wheel to your Printer.
The Flex Wheel has been designed with numerous attachment holes located at convenient points which allow for complete flexibility when attaching and using the Flex Wheel with your existing 3D printer. These attachment holes include 4 x 3 mm holes located at each corner and 2 x 5 mm holes which are located along the lower edge (diagram here).
Bowden Cable Set Up.
When used in the Bowden cable configuration the Flex Wheel is compatible with just about every printer on the market.
The Flex Wheel can be either attached directly to your printers frame via the combination of 2 x 5 mm holes (ideal for 20 mm aluminum extrusion) or these holes can be drilled out to 6 mm which is ideal of 25 mm t slot.
A simple stand has also been designed and can be downloaded from our printable accessories page. This stand can be adapted and will allow your Flex Wheel to be mounted in just about any position you desire whether it is attached to your printer or used as a completely free standing unit.
While the Flex Wheel was designed with the Bowden system in mind the power output and printing speeds can be significantly improved by using the device in the direct drive configuration. There are however some limitations to be considered which are discussed here.
Calibrating E steps.
As the diameter of the Flex Wheel is much larger than the Hob gear you are are currently using, coupled with the fact that the Flex Wheel uses a high precision planetary 30:1 gear box your E steps will need adjusting.
There are numerous guides out there on how to accomplish this and you would likely have already tuned your printer before, however if you need a refresher I found this great extruder calibration guide on ‘Matt’s Hub’ it is concise and easy to follow.
Reducing micro steps on control board
If your stepper driver runs at 1/32 micro stepping you will likely end up with a step rate that is very high indeed. You can reducing this step count by reducing your micro step rate to 1/8 or even a 1/4. Reducing your micro step rate will provide more torque for your stepper – which is a bonus as it will allow you to push your Flex Wheel even harder.
Loading and unloading filament.
While the Flex Wheel can be loaded and unloaded by a quick release function by simply loosening off the 4 x tension screws and inserting or withdrawing the filament manually we have found in practice that this is not the most effective way and is usually impossible when when managing very flexible filament. The Flex Wheel can operate at high speeds with significant loads so why not let the machine do all the work.
The following routine for Bowden setups works very well and takes just over 60 seconds.
- Unscrew and remove Bowden coupling and tube from outlet point.
- With printer software extrude 200 mm @ rate 800 mm /min.
- Cut end of chosen filament at a 45 degree angle and insert into stainless steel tube on the inlet side.
- A short time later filament will exit the unit, any debris that may be in the mechanism will also be ejected at this point – save it going into your hot end
- Reattach Bowden tube, extrude additional length @ 800 mm /min until the filament reaches the top of your hot end, extrusion length will depend on your particular Bowden tube.
- Extrude another 100 -150 mm @ 200 mm / min to prime hotend.
- Good to go – Print away.
To unload we recommend the following –
- With you hot end heated up to printing temperature unscrew the Bowden Coupling from the outlet side of the Flex Wheel and withdraw filament from tube.
- Cut of tail as it usually forms strings and blobs as it is withdrawn from your hotend (these can easily become dislodged in your extruder mechanism and are best discarded). Make your cut at a 45 degree as this help with loading next time.
- Reverse filament by required amount @ 800 mm /sec.
Full video of the above procedure Loading / Unloading Video
You are now ready to run in your new extruder.
The Flex Wheel has been designed to run with the common 4988 stepper drivers however to obtain the most out of your unit these drivers need to be run at close to their maximum with plenty of cooling.
If you really want to push your extrusion control to an even higher level consider fitting a high powered stepper driver for example the DM542T available at our affiliates site – Steppers Online.