As I am fairly new to 3D printing, I am learning a tonne about what not to do. One of the biggest issues I have discovered is that things that look good in CAD can look absolutely terrible once printed, given the resolution of the printing or the limitations of FDM 3D printing. Today I wanted to talk about three different, but similar errors I made: making a part too thin to print correctly.
Back corner of the cab
First up – the back corner of the cab. As the backside of the cab is curved, it thins quite a bit at the very back corners.
When you bring this into Cura to slice it for printing, the problem becomes obvious.
The solution to this is to thicken the back wall of the cab, which I did by adding a flat piece to it:
Once you bring that into Cura, you see that the narrowest part is now at least 1mm thick, so the piece shouldn’t be so weak.
The next piece I tackled was the fenders. They were originally 0.25mm thick, which means that they were just over one layer thick when printed at 0.2mm and only two layers thick at 0.1mm. This meant they basically didn’t print at all.
The solution to this problem is two-fold: thicken the fender up to 0.5mm and also only print at 0.1mm (considered Fine quality).
Top of the windshield
This is actually entirely my error. I made the windscreen and frame around it taller than the sides or back of the cab. This meant when I cut up the model to slice, the top of the windscreen disappeared. Oops.
The new printer board for my 3D printer finally showed up, so I got to printing the first print of my 1956 PANG. It was less than a full success. As you can see in the pictures below, I have a bunch of work to do.
As can be seen on the build plate, a bunch of details didn’t come out right – the biggest of which was the top of the cab for some reason completely failed to print correctly. I also accidentally selected brim intead of skirt, so I had lots of cleanign to do.
The sides of the truck aren’t very smooth, and a bunch of the finer details simply didn’t print.
So what next? First of all,my printer needs some upgrades:
A part cooling fan (the Ender 2 lacks it by default)
Belt tighteners (and the belts replaced with metal-core of some kind)
A more modern Marlin (the firmware that runs the printer)
A lot more tuning
On the truck, the first thing I am going to do is shrink it by 25 to 30%. It is too large for what I want. Then I need to some work on the model itself
Thicken some of the walls so that they print, especially the fenders, which didn’t print at all
Clean up some of the smaller details, possibly removing them for now
I finally got around to laying out the 1956 PANG for the first printing. As you can see from the pictures below, I am trying to remove the need for supports which will mark the surface of the final print.
I chose not to break out the rear section or the bins for initial printing. I likely will in the final version, as it will speed up print time and make it cleaner.
One final note: I am certain that there will be tweaks needs to be this and I am missing things, namely an interior and side mirrors to start.
Build Something 2018 continues and I have been pretty quiet for the last week. Part of this is because I am waiting on the warrantied printer board, so motivation is low. Also been busy with other things. But today I kicked myself into gear and go the first printable draft done of the 1956 PANG. Take a look below (the red rectangle is 32mm high and is there for reference):
Well, Build Something 2018 is well underway at Lead Adventure. You can follow all the entries, including at least two other 3D printed things, over on the subforum.
And what of our 1956 PANG tricycle truck? Yesterday saw a lot of work on the back end. As of two days ago it looked like this:
I really didn’t like the aspect ratio of the truck – height, etc. So I completely rebuilt the back end so it was taller and thus looked narrower:
Today I started working on the front end, which is a lot harder. It has a lot of curves with curves, so it going to be a real challenge to do well. I am not overly happy with the look (too wide and squat) so might rebuild the front. Here it is in exploded view.
What I love about modelling this way is that if you don’t like something, it is trivial to rebuild it. Play with the ratio, etc.