I have created a budget 3d printer using parts of old computers, specifically I used the CD drive mechanisms for the x,y and z axis. This printer is similar to the curiosity E-Waste printer, as seen here: Link
After quite a bit of time working on it I have got to the point where my printer should be able to print, but unfortunately, I have encountered an issue. The layers in which the printer prints fluctuate in height, and so when the nozzle travels over the lower layers to do the next layer, it hits a bump, misses some steps and becomes mis-aligned. I have never owned a 3d printer before, but I think that it is likely that the problem I have which causes the prints to not be flat is likely a common 3d printer problem. However, with commercial 3D printers, these bumps would probably only cause a drop in the quality of the print and not a complete fail; it is only due to how weak my motors are that the nozzle will miss a step with even the slightest force against it.
I have thought about why the layers may not be flat and I have come up with a few possibilities that I think are the problem. I do not know if these are in fact the source of the issue, but these are the things that I have considered so far.
- The nozzle height when starting the print. If I lower it then the layer height will be smaller, and so there is less chance for it to be higher in different places. However upon testing this I found that, due to the reduced height upon the first layer the nozzle would get stuck.
- When the nozzle changes direction, for example at the edges of the print, there is significant vibration and it is possible that this cause the filament to overlap and not be flat. The vibration is due to the nature of my printer and would be very hard to reduce. A solution could be some kind of software fix, but I do not know enough about this to do so.
- Maybe the speed at which I am printing is not good. I'm printing currently at an incredibly slow 40mm/s.I have tried different speeds but at low speeds there is over extrusion and at high speeds, the vibration is too much.
- I have tried experimenting with flow rate (100%,75%,and 50%) and at the moment I am using 50%. This is because my extruder motor is a bit weak and often misses steps, also the filament requires considerable force to push it through. Is this normal?. My idea is that maybe there is too much filament being extruded and so if I lower the flow rate the print will not create bumps.
- The filament curls slightly when it comes out of the nozzle and I have tried to fix this by cleaning it and printing faster but it is only reduced. I'm printing at 200° currently; Will higher or lower print temperatures cause the filament to curl less and be more easy to push through the hot end?
As you can see there are a lot of factors in which I need to consider if I want my printer to be able to print correctly. And unfortunately, with my printer it is either perfect or a failed print; there is no in between. Due to the weak motors everything has to be exactly right, or the nozzle will get stuck.
I am not sure how to add videos here so I will instead. add some photos of the prints, and three photos detailing how the prints fail.
Below is an image containing the 6 most recent prints in which I played around with the different factors mentioned above. The top middle one is the most recent one. The object i am trying to print is a simple cuboid.
This is what the first layer of my most recent print looked like. There is some kind of gap in the middle for some reason, but I don't think that is the source of the error. The print appears to have adhered well, at this point and it is relatively flat.
This is what the second layer of the print looked like, notice how the lines are wobbly and not very neat. There is also a small area of higher height in the bottom left corner which inevitably causes the nozzle to get stuck.
This is the print after the nozzle hit the now cooled down blob, missed some steps and then was misaligned. It then goes on to print the next layer in the wrong place and gets stuck very badly.
Thank you, for reading this. Any help would be much appreciated