Tech Tips: Skins…And Print With Fine & Large Nozzle
Hi there. I know we wanted to do more video entries, but as I looked back at my notes this seemed like a good story…This has been a long time in the making, and it appears I have finally figured this out.
How to effectively use a large nozzle in combination with a small nozzle to increase 3D print speed/ strength, yet still retain fidelity?
In the past, companies like UTC had to choose between fast prints and quality. This will combine the best of both worlds.
Today I successfully 3D printed with a 0.4mm nozzle and a 0.8mm nozzle on the same part. The method I used to achieve this is mainly CAD based, but the process is quite easy and can be applied to any solid model.
I achieved my original goal of combining nozzles, but a pleasant side effect is now we can do the same with a rubber / TPU material. Imagine a shadow board with non-marring pockets…
What I learned today is that you must keep all settings a multiple of each other.
0.4mm nozzle / 0.25mm layer height / 0.42mm layer width
0.8mm nozzle / 0.50mm layer height / 0.84mm layer width
This keeps the math simple and the slicer likes it much better.
In the future I would like to try some 3-1 and 4-1 settings.
The Good, the CAD, and the Ugly
My goal here was simple, create a basic shadow board example using the big nozzle for the base and the fine nozzle for the pocket.
The blue part would be the actual real life part that goes into the board. I was able to use a few SolidWorks features to create the pockets in the base and the skin that sits between the real part and the print. This skin will be the high fidelity layer.
The Cookie Cutter
This is the first step. I need to determine how thick my skin is… My first attempt was at 1.2mm thick, but that is really too thin. I settled on 2.4mm for my last attempt.
If the skin is too thin, it can tear during print and doesn’t look very good. You want to go as thick as possible for the skin.
The Feature I used is called MOVE FACE. Just select all the faces of the real world part and offset them by 2.4mm
I cut the top flat because…
With the cookie cutter in place, I perform a CAVITY feature in the base.
Now I can suppress the cookie cutter.
Give Me Some Skin
Now all I need to do is make a copy of the cookie cutter and perform a SHELL feature on it.
Again, it will be at the desired thickness. In my case that was 2.4mm
So there it is…
This is what a 0.8mm looks like before the skinning. The stair stepping is very heavy.
With new skin
Just create 2 processes in Simplify3D for each nozzle size and apply each process to the parts as needed.
Very easy to do, just follow the rules above.
So in conclusion, this is actually rather easy to do if you have some basic CAD skills.I think one day our software companies will make this easier, but at least we have an option now. If you need a fast / strong print but you still need high-resolution features, remember this procedure. I am quite pleased with the results, I think you will be too.
My next test will be adding NinjaFlex into the pocket.
The final result… (14pt font, under 45 minutes to completion)