My journey into the world of 3D-printing as a total novice

[Grunticus]

Seeing the spectacular 3D-printed stuff Reskit and now Lukgraph (and others) were putting out renewed my interest in the subject. It's maybe ten years ago I investigated what was possible in a home environment and was not impressed at the time, but now I decided to give it a go with all the leaps made in printing setups and printing quality.

I decided to make a living post here to document me treading in to this field as a completely blank novice, and report what I come across along the way so others may benefit from it. Online guides are often confusing, written by experts who don't remember how they felt when they started. I am not going in-deep on every aspect or the in-depth technology behind it. Just what I come across while entering this (for me) new and exciting field in scale aircraft modelling.

 

The first decision to make was to choose what type of printer suited best my modelling needs (for 1/32). There (generally) are three types:

 

SLA: solidifies resin with laser light, streak-by-streak. Detail quality: excellent
DLP: solidifies resin with UV light, one complete layer at a time. Detail quality: excellent
FDM: Extrudes solid plastic through a heated nozzle. Detail quality: pretty good

 

Here's a good write-up explaining the strengths and weaknesses. 

 

SLA/DLP, the good: excellent quality, 0.01mm printing is possible. SLA laser-streak by laser-streak, DLP layer by layer. What does this mean? If you print four fuel tanks at once on an SLA printer it will print one tank art a time, and the DLP will print all four simultaneously because the DLP prints one layer in one go. The quality between both will be equal.

SLA/DLP, the bad: much much more dirty than FDM. You will nee to work with toxic / skin and lung-sensitizing resin, and use lots and lots of Iso-Propyl alcohol. I have worked in the chemical industry all my life, and once you are sensitized you will never ever get rid of that. The slightest exposure to whatever you got sensitized to will cause you to go ill very quickly.. It is no joke.

 

The chemicals will all need to be stored and handled, and you will need PPE and a well ventilated room. After every print you must clean all parts that came in into contact with resin meticulous, wearing at least rubber gloves. You will need silicone trays, spatulas, wipes en-masse. All ready to grab and use. You will need a dedicate area. 

 

The reward: spectacular detail on you prints. But more on that later.

 

So I choose DLP printing, an Elegoo Saturn 4 16K (not the price but the resolution 🐵 With it, I bought their washing and curing station, and a carbon filter unit that sucks air from the printer and emits it through (of course) the carbon filter. On my first test print, this worked well.

 

Now comes the next decision. I want to print a 1/32 Farley Fruitbat and that is not available for download as a file (while there are hundreds of AIM-9Js available for download for example), so I will have to 3D CAD it myself. I am a total newbie in this field, but I am very computer-savvy. 

 

What software will I use for CAD?

 

There are tons and tons of options. The matter of preference is very personal. I started with FreeCAD because my computers run Linux Mint OS. FreeCAD pretty good but the interface is confusing, and it only recently matured into release v1,0, after more than a decade of development. The consequence of this is that many many online tutorials are for older versions that have a different layout or missing icons or have other icons, etc.

 

So in the end I settled for Fusion 360, the most widely used (by hobbyists) Windows CAD software, with untold numbers of tutorials available. My PCs are dual-boot Linux / Windows because occasionally I need to use Office 365. And now Fusion 360. It is available for free, with a so called Personal Use license. It is restricted in that you can edit a max of ten designs. Want to start design number 11? No problem. Make number 1 read-only and you can create and edit 11. Later need to redesign design number 1? Make design number 4 read-only and you can! This is how their restriction works. There is also some functionality missing but those are not important for what I want to do. After 3 years you have to re-apply for this license.

 

When your design is ready you save it as the industry standard .STL file format (but there are more), then put it through a so called slicer, a software that makes digital slices of your file that can be sent to the printer. Again, there are dozens of software options. The printer always comes with this software or a downloadable link, and a very widely used on is called Chitubox. Chitubox comes free and does all you need. There's a paid option that can do more. From within this software you can print to the printer directly over the the LAN (home network), or via a USB stick that you stick into the printer. The slicer software needs to know what printer you use as each printer needs specific settings. In practice, the slicer software has most used printers pre-installed and selectable as a profile with the correct settings for that specific printer.

 

In short, the whole process goes like this:

 

• Design the part
• Export to .STL format
• Slice in a slicer software
• Send to printer
• Remove print from build plate with a knife
• Wash print in IPA (Iso-Propyl alcohol) for 5 minutes in the machine, or in a container using a brush
• Cure in a UV-Curing machine for 5 minutes (or use a UV torch, or place it in the sun, both will take long)
• In the mean time return the unused resin from the vat back into the bottle though a filter
• Clean the printer's build plate and resin vat and clean up any mess you made. Any particles left in the unused resin or on the build plate can ruin your next print and even damage the UV emitting LCD of the printer.

 

Uncured resin is environmentally toxic. Dispose of resin-drenched wipes and what not sensibly. Have two containers of 5 ltr IPA at hand, one for a first wash (dirty IPA that is used over and over, to a point), and one for a second wash (cleaner IPA, that is used until the dirty IPA become too dirty and then 'cleaner' IPA becomes the dirty IPA and you use fresh IPA as 'clean IPA). When exactly that moment will be, I have no clue...

 

I hope this all makes sense ☺️

 

Tip #1: if you mess up your design in a major way, don´t try to correct but start over. It will help you getting to understand what you are doing in the software. Fusion 360 has an undo button 😎

 

Next post: printing the Secapem container and explaining what you see in the photos. I first have to finish the design below. This is what I was able to design after just one morning of watching tutorials and playing with Fusion 360: a 1/32 Secapem 520 target container for my Belgian F-104G target tow.

 

Cheers, Leon

 

p.s.  I am sure I will make mistakes in this write-up, as I am still learning.

p.s.s. comments, criticism, corrections welcome!

 

Edited June 11 by Grunticus
spelling

[BiggTim]

Looking good!! 

[Dave Roof]

• In the mean time return the unused resin from the vat back into the bottle though a filter

 

This isn't really necessary. I run 14 printers almost every single day, for 8 to 12 hours each. I've been doing this four straight years now, and have never once did that. The only time I have ever emptied a vat is when a fail punctured the FEP, and fortunately, that's only happened twice. I literally just refill the vat after every print and have never had a problem.

 

All that really does is increase your chance of making a mess. 

 

  As far as cleaning goes, this is my process. I have an ultra sonic cleaner and 3 washing stations. All are filled with denatured alcohol (the fuel type by Klean Strip). 

***If you have an ultrasonic cleaner with a heating element that can be turned off, turn it off. If it has a heating element that you can't turn off, don't use it with alcohol.

 

The whole build plate (I use mostly Elegoo Mars 3 printers) gets held in the ultrasonic cleaner for 15 seconds. This is long enough to get most of the excess resin off the parts.

Then, 2 minutes in the first wash station, 2 minutes in the second, and 1 minute 30 seconds in the last. Also, I typically clean two plates at a time.

Remove the build plate and shake off into a large trash can (the alcohol evaporates within a couple minutes). 

Hit the build plate and parts with a hair dryer on high heat for a minute or so until all of the remaining alcohol is gone.

Remove the parts from the build plate, remove the parts from the supports, then cure. 

Give the build plate a quick wipe with a paper towel (I use the thicker, blue automotive type), put back on printer and go again. 

 

*The heat from the hair dryer not only dries them faster, but it softens the supports/rafts making them easier to remove from both the parts and the build plate. This is what my parts look like every single time. 

 

[Grunticus]

1 hour ago, Dave Roof said:

• In the mean time return the unused resin from the vat back into the bottle though a filter

 

This isn't really necessary. I run 14 printers almost every single day, for 8 to 12 hours each. I've been doing this four straight years now, and have never once did that. The only time I have ever emptied a vat is when a fail punctured the FEP, and fortunately, that's only happened twice. I literally just refill the vat after every print and have never had a problem.

 

All that really does is increase your chance of making a mess. 

 

  As far as cleaning goes, this is my process. I have an ultra sonic cleaner and 3 washing stations. All are filled with denatured alcohol (the fuel type by Klean Strip). 

***If you have an ultrasonic cleaner with a heating element that can be turned off, turn it off. If it has a heating element that you can't turn off, don't use it with alcohol.

 

The whole build plate (I use mostly Elegoo Mars 3 printers) gets held in the ultrasonic cleaner for 15 seconds. This is long enough to get most of the excess resin off the parts.

Then, 2 minutes in the first wash station, 2 minutes in the second, and 1 minute 30 seconds in the last. Also, I typically clean two plates at a time.

Remove the build plate and shake off into a large trash can (the alcohol evaporates within a couple minutes). 

Hit the build plate and parts with a hair dryer on high heat for a minute or so until all of the remaining alcohol is gone.

Remove the parts from the build plate, remove the parts from the supports, then cure. 

Give the build plate a quick wipe with a paper towel (I use the thicker, blue automotive type), put back on printer and go again. 

 

*The heat from the hair dryer not only dries them faster, but it softens the supports/rafts making them easier to remove from both the parts and the build plate. This is what my parts look like every single time. 

 

 

 

Hello Dave,

 

First of all, thanks you so much taking the time to respond. Your statement of leaving the resin in the vat sounds very interesting as indeed it is a messy affair pouring it back in to the bottle. I would not print very often. Maybe weekly / monthly, I don't know yet. Would the resin in your experience start to solidify slowly if I left it in the vat for, say, two weeks? The shutters outside the window in my modelling room are mostly closed so there will be no natural UV light entering.

 

Thank you for the good advice you provide, using an ultrasound cleaner for the plate (which is the hardest part to clean on the Saturn 4) and using a hairdryer to speed up the drying process after washing. I'm taking notes.

 

Regards, Leon

[Dave Roof]

1 hour ago, Grunticus said:

 

Hello Dave,

 

First of all, thanks you so much taking the time to respond. Your statement of leaving the resin in the vat sounds very interesting as indeed it is a messy affair pouring it back in to the bottle. I would not print very often. Maybe weekly / monthly, I don't know yet. Would the resin in your experience start to solidify slowly if I left it in the vat for, say, two weeks? The shutters outside the window in my modelling room are mostly closed so there will be no natural UV light entering.

 

Thank you for the good advice you provide, using an ultrasound cleaner for the plate (which is the hardest part to clean on the Saturn 4) and using a hairdryer to speed up the drying process after washing. I'm taking notes.

 

Regards, Leon

 

As long as there is no sunlight hitting the printer, you can leave resin in the vat for weeks, and even months. At one point last year, two of my printers went unused for close to 3 months (both Saturns). When I did start to use them again, all that was needed was a good stir of the resin. At the moment, my office/print room has no windows (it's the 'basement' behind what used to be the garage, which I've converted into a living space). However, when I do add a window, it will face the front of the house and will be under the front porch. Still no direct sunlight. When not using it for a bit, you can even cover it with a small towel to help keep more light out. 

[LSP_Kevin]

7 hours ago, Grunticus said:

Would the resin in your experience start to solidify slowly if I left it in the vat for, say, two weeks? The shutters outside the window in my modelling room are mostly closed so there will be no natural UV light entering.

 

I tend to print for projects, with many months between them, and rarely empty out my vat. The contents just need a good stir and remix before you print again. I haven't printed anything at all so far this year, and I'm pretty sure the resin will be good to go when I get back to it. The plastic covers on resin printers are UV-blocking, so unless you've got a leak somewhere, you should be fine.

 

Kev

[Dave Roof]

12 hours ago, LSP_Kevin said:

 

The plastic covers on resin printers are UV-blocking, so unless you've got a leak somewhere, you should be fine.

 

Kev

 

Not completely. Even with the cover on, if the printer is exposed to direct sunlight, it can and will cure the resin in the vat. Had it happen to two printers at my old house as they were on a shelf next to a window.

[Iain]

I'll second Dave on this - I've had exactly the same happen to me...

 

Iain

[wunwinglow]

3 hours ago, Iain said:

I'll second Dave on this - I've had exactly the same happen to me...

 

Iain

,,, and look out for reflections, I thought I was safe until a neighbour parked her car opposite and the windscreen reflected the sun STRAIGHT into my garage JUST as I was clearing parts off my FormLabs 2 platform. 27 hour build ruined in a couple of seconds.....

 

wun

[Grunticus]

Tomorrow is printing day fellows..The build plate shown below is not the Saturn 4's. I am downstairs and it is upstairs, off, so this shows the generic build plate of Elegoo's 'Satellite' slicer. The slicer connects to the printer over the network and this is a fresh software install so the printer has not been added yet.

 

The bottom end of the pods is pointed upward so the unprinted resin can egress while the plate is raised (while upside down). I am excited...

 

@Dave Roof, any last exposure timing tips if you could? I use Elegoo's ABS-Like resin 3.0 Pro.

 

[Dave Roof]

54 minutes ago, Grunticus said:

Tomorrow is printing day fellows..The build plate shown below is not the Saturn 4's. I am downstairs and it is upstairs, off, so this shows the generic build plate of Elegoo's 'Satellite' slicer. The slicer connects to the printer over the network and this is a fresh software install so the printer has not been added yet.

 

The bottom end of the pods is pointed upward so the unprinted resin can egress while the plate is raised (while upside down). I am excited...

 

@Dave Roof, any last exposure timing tips if you could? I use Elegoo's ABS-Like resin 3.0 Pro.

 

As I don't know what your current settings are, it's difficult to suggest exposure settings for your print. I also don't use ABS resin, and not sure if anything needs to be adjusted for that type.

 

However, might I suggest changing the orientation of your parts? This is how I support my 32nd fuel tank nose cones and never have any issues. A lot less clean up is needed after the supports are removed.  

 

[BiggTim]

I totally agree with Dave on the orientation of the parts. I also use high speed resin or standard resin for almost everything. 

[LSP_Kevin]

10 minutes ago, BiggTim said:

I also use high speed resin or standard resin for almost everything. 

 

How does it compare to the ABS-like varieties? That's all I use, and I like the fact that it's not overly brittle. It also works will with the 50 micron layer heights I use with my OG Saturn. I assume that standard resins replicate details better, but I don't really know, as I've never tested them (coupled with the fact that you'd barely notice a difference at 50 microns anyway).

 

Kev

[Grunticus]

10 hours ago, Dave Roof said:

 

As I don't know what your current settings are, it's difficult to suggest exposure settings for your print. I also don't use ABS resin, and not sure if anything needs to be adjusted for that type.

 

However, might I suggest changing the orientation of your parts? This is how I support my 32nd fuel tank nose cones and never have any issues. A lot less clean up is needed after the supports are removed.  

 

 

5 hours ago, BiggTim said:

I totally agree with Dave on the orientation of the parts. I also use high speed resin or standard resin for almost everything. 

 

Thank you guys. I will adjust it accordingly. I was under the impression that an approximate 45 degree angle increases surface smoothness. But what do I know. Less cleanup is a valid point.

[gunpowder]

I came across a website somewhere that gave the best angles for different printers. I cant find it now typically. I use an elegoo saturn 4 ultra and the best angle for that is 66 degress if i remember correctly.