UV resins are not good for your health. Avoid skin contact if you don’t want to develop a life time of allergies or immune system over reaction. WERE GLOVES WHEN EVER HANDLING RESINS!
Is it worth it?
Does handling the messy resin, washing the prints then curing them worth the time an effort. I have been 3D printing for quite a while now, My printing farm of consist of 3 printers with parts to make from two more machines. I do make quite a lot of small parts, this is a struggle at times to get detail and strength. The restriction is the nozzle size and layer height on my FDM printers. I was going to make a dedicated mini FDM printer but do I ?
Well the biggest game changer for me is the wash and cure machine, it takes care of the mess in two easy processes. The though of scrubbing the prints was not appealing. I can imagine that nice resin is going to splash all over the place.
Next was the price, these have fallen quite a bit lots over the years. The endless choices to choose from, each part of the world will have different choices i bet.
Another reason
To print ultra clear transparent lens covers for lights. I have design and printed many light fittings for home and our camper. Why do i make such things?, I just don’t like what is available off the shelve. Using ABS or PLA and vapour smoothing does give good result but I know I can do better. Ultra clear lenses / defusers is what i want.
I have a cheap CNC engraver/laser machine kit I built. Its been very useful for engraving and making PCB. Do I spend the money to up grade this? I did look into upgrading what i have with new parts. The CNC still does what I want.
I reckon I will get more use from the resin printer. As i said i want to make smaller detailed parts.
This mind battle took me around 12 months to think through.
Taking the plunge
I did quite a bit of research , joined a few forums and watched lots of Youtube videos. Its a new world to my FDM printing world, the slicing process is different, there’s printing angle, supports and cure times to consider. Having many conversations with a work colleague whos into resin printing helped.
Theres quite a few brands of budget resin printers out there.
My thinking is dip my toes into the resin world first, start small and get a feel for it first.
If its not for me then not much lost.
My selection ended up being the Anycubic Photon Mono SE off eBay. It was a good printer to start with, looked like a solid machine. A assortment of resins was purchased too, some normal and tough resin to try.
While waiting for the printer I was told its quite messy process with out a wash and cure. I didn’t really have the budget but it was a safety factor, so back on eBay, I ordered a Anycubic Wash and Cure 2.0.
The resins are a bit pricy but it goes a long way I found, hollow out your prints.
I follow these 3d printing Youtubers.
The Anycubic Photon mono SE and Wash and cure 2.0
When I received these two machines in the post I discovered I need more room in the printing farm room. Time to make a new bench in the attic, more lighting and a power. The photon SE printer was mostly assembled and all steel construction. I installed the slicer that came with the photon call photon workshop. It seemed a bit clunky to use and a laggy. Unfortunately I could not use prusa slice as the file format is different To what the photon needs. I did set up the Mono SE profile in prusa, maybe I missed something. Watching Youtube I notice a slicer called Chitubox is used quite a bit.
Chitubox for me is much easier to use, it runs much nicer on my iMac.
The upside down world!
These prints are upside down man! (Figure 3) Printed on a build plate layer by layer, each layer peeled off the FEP (figure 1). The what? FEP
The FEP is where the magic occurs (figure 1), the UV light passed through this film and cures the resin layer. The Build plate moves up to peel of the exposed layer (figure 4) from the FEP. Down again to the next layer thickness, the process goes on and on till its finished.
The trick I found is the bond to the build plate must be stronger than the FEP film adhesion. If not you have a failed print. You can’t really see much, you can hear the sound of the print pealing from the FEP on the up cycle.
TIP, spray PTFE or silicone spray on the FEP to give the build plate a fighting chance. I learnt this from a colleague, its winter and cold when writting this, the resin doesn’t like the cold!
Between the FEP film and UV light is a MONO LCD screen (figure 2) that allows UV light to pass through were you want it (figure 4). Sort of like exposing silk screening mask. If your into PCB making using the UV exposure technique, its very similar to this.
I got my head around that the resin print is pealed off the FEP, I now understood what forces are at play. Orientating your prints model in the slicer on an angle to reduce the pulling force required, not flat helps to reduce these forces. Figure 5 shows how you should not do it, I wanted a nice smooth flat surface. The PTFE spray helped the pealing process, so no fail.
To have the best success you orientate your prints around 30deg off the build plate. This reduces the pull suction forces when the build plate is lifted for each layer cycle. Printing support is another topic but very important. Watch Youtube for this.
Clean up
Ok your print has finished and not failed, this is very good!!
On the build plate is your print with a nice coating of runny uncured resin on it. Don’t get this resin on you skin, wear gloves!
I slide over the drip tray i have next to the printer, remove carefully the build plate and angle it towards the resin vat. Gently scraping the resin off the top of the build plate into the vat. Why waste it.
Now place the build plate with the printer object into the cleaning container full of methylated spirits. Place this on the wash and cure machine. Set a appropriate time of say 14 minutes. A magnetically coupled stirrer in the bottom of the tank will agitate the solution. When the time is up the print can be pulled out, then separated the print from the build plate with the paint scraper. Let the print dry.
This is when i remove the supports it they are present.
Once dry the print can be cured.
Place the turn table on the wash and cure machine.
The print is placed on the turn table, put the UV blocking cover on.
Set the exposure cure time to say 10 minutes. Watch, turn baby turn.
You’re print is now ready.
This is a simplified description but I hope you get the idea. its a few steps and my not be what you want to do.
Some examples of my first prints
Jayco LED boot light
This light is for our Jayco camper, the base is printed in PETG FDM PRINTER, the lens is clear resin on the mono printer. A bit of wet rub sanding and the plastic polish on the lense. Under the lens’s is aluminium backing tape that acts as a heat sinking and reflector.
The LED’s are two bits of led strip lights cut up, this is wired to the on off switch
Touareg rear light access caps
To replace the rear brake light bulbs, the need to remove the light lens body from the car body is required. To do this first remove the screw access caps, these usually break! 🙁
These caps are expensive at $50 a pair, that is just robbery from VW in Australia.
I found a cap design on Thingiverse and tried to print it on my FDM printer. Well it didn’t turn out good and was fragile . The model didn’t look right either.
Now that I have the resin printer I though let’s draw it from scratch. Fire up Chitubox slicer and slice it.
Wow wee this looks really nice sliced, it has the plastic injected look. Save it to a usb stick and get the mono SE printing.
I used tough black resin, it has flex and much harder to break.
The photos above is my version 1, my new updated version 2 has thicker locking tangs.
The print was at 0.05mm layer hight, it could be finer. A little wet rub and polish will make a big difference.
More to continue
More to continue