Hey there,
I thought I’d share my first test with the Form2. Obviously, it’s straight out of the printer so no sanding and no prime yet. I’m pretty happy of the results except that my base started warping after a certain layer (see 4th image). I guess I should have put a few support on the bottom of the base huh…? Any thoughts?
Anyways, I’m really happy I bought this! I have a few more tests queued up!
looks very good, Id thicken up the base a little, that will help with the warping.
Just adding supports should help the warping. It is better to have a bit thicker base as suggested to help keep the part from warping over time especially during post cure.
You could also try setting the base at vertical and orient it perpendicular to the wiper. This would run the stress along the length of the base instead of the width.
To slightly echo what @Joe90 mentioned you should thicken up the base a bit. When I am dealing with a part with a thin base I will thicken it up, then sand/shave it down to the desired thickness.
Ok thanks for the info! Would buying a UV machine help for the post-curing warping? I don’t really know the advantages of a UV machine.
Putting some supports on the base to hold it in place will help it a bit, also avoid too much heat while curing since that will warp thin parts as well. UV curing is a bit more controlled than putting out in the sun–it’s cheap and easy to do as well: https://www.youtube.com/watch?v=mahcMOpeZkM&t=2s
Someone correct me if I am wrong here…
A UV chamber (or exposing to UV light in indirect sunlight) is a necessary part of the process. From what I understand the printer only partially cures the resin…enough for you to handle it, remove supports, withstand the IPA, etc. The UV light finishes the bonding process and strengthens the product. As far as I know the item shouldn’t warp in the chamber unless it was in way too long or maybe becomes too hot.
The warping you are seeing is because of 1) how thin that section of the part is, and 2) the peeling process. When the part is peeled away from the PDMS layer it is too thin to support itself. either more supports, different orientation or thickening the base (or a combo of all of those) would dramatically help.
Hum, I’m just not sure to understand why the UV chamber is “necessary”?
This is spot on. Parts straight out of the printer are in a ‘green’ state where not all of the photoinitiators have reacted. UV curing helps to ensure that all of the photo-polymerization reactions have completed and the part is at its final mechanical properties.
UV curing can cause parts to warp. Warping forces pull inwards parallel to the layer lines. When you post-cure and activate the final photo-polymerization reactions, the inwards forces compounded with the heat can cause warping. Orienting parts at around 45 degrees equally distributes these inwards forces and combats warping. Thickening parts or adding more supports also makes for an easy fix.
Arf… I’m sorry guys is there a way to vulgarize it a bit, I’m not sure I understand how it helps compared to just letting it dry overnight on the supports.
Edit: deleted my analogy cuz it was terribad.
In plain, simple terms, letting it try just allows the water/IPA to dry off the surface. However the internal chemistry of the mostly cured resin is not finished. As @Frew stated UV curing finishes off the chemical processes in the resin. You could use the piece as a demo/prototype piece…heck I have done it before. But the piece will end up stronger and lasting longer if you UV cure it.
Read this: https://formlabs.com/blog/how-to-post-cure-3d-prints/
or this super technical document
So not UV curing with a machine will make it more fragile? Will it warp over time if I dont do it?
What about curing it near a lit window?
What happens if I over cure it? I looked at the docs and it looks so technical and easy to screw up. Im just not sure of the benefits of curing it versus adding another that could destroy my print?
By now I know I look like a complete idiot who does not understand but Im really confused about the necessity of UV curing in a machine versus juste letting it settle in a normally lit room.
Im also confused about the fact that when I read about resin left in the resintank and the resis cartridges themselves, they have to be kept away in the dark of an abyssal underground bunker because indirect daylight can cure it, but now Im told that you actually need a machine to cure resin, and it comes with a possibility of destroying your print if you dont put it and the right angle, right placement, right time, etc.
The resin in the printer will not cure because the orange cover protects it from UV light sources. Same with the cartridges, in the black containers. Just keep everything (your printer, extra trays (with covers on), cartridges, etc) in an indoor room, at room temperature, out of direct sunlight and you are fine.
With regards to the print, lets leave the technical jargon out. Here’s almost exactly what I do…others can chime in and tell me I’m wrong or right. I made the following UV chamber. Small pieces I put in for at least 30 mins, usually turning once. Larger, thick pieces up to 2 hours. I keep the pieces at the bottom of a box roughly 2ft cube so they do not get too hot and warp.
That’s it…my pieces come out non-tacky and tremendously stronger than before curing. Prior to curing you can often use your finger nail to put scratch marks in your piece. Post curing this just isn’t the case.
As far as UV chamber vs the sun. I myself have never used the sun to cure. If you go that route, I wouldn’t put your items in direct sunlight because of the heat. As far as time I am not sure. I have read some FL employees leaving their parts on a window sill all day and they end up curing just fine. To me none of this is an exact science…just experiment, find out what works best for you and do it. Just take our word for it that UV curing is a necessary part of the process of finishing off a print.
And don’t worry about looking like an idiot. I recently looked back at my first few posts here and wow, what a noob I was. 
We all start out as noobs! It’s a learning process.
As far as curing goes, it also depends on the material you are using. It’s been my experience that curing the tough and durable resins take longer than the standard resin. And the amount of time difference can be quite a bit.
This is true. I mainly use standard resins. @csauve is correct that durable and tough and maybe some others take quite a bit longer.
Thanks for you continuous help!
Can you define small piece and big piece?
So to resume: I buy a UV machine, make my own 2 ft UV chamber, since I have grey resin I bake 30 min for small pieces and 2h for big pieces, turn them over once halfway into the process and then I can sand them and prime them. Nothing more complicated or nothing that could make my print melt if I follow those simple guidelines? Just looking for the most dumbed-down explanation 
When should I put the print in the UV chamber? When is it too late to cure it in the UV chamber? Overnight? 2 weeks?
I actually have my collectibles by the window and was intending to put my own 3d prints there too eventually. Once primed, can I put them there or for eternity they are bond to melt because of the heat?
Oh btw, about having the printer in direct sunlight, here is my setup. I’m in Canada no it’s not hot at all and during the summer I have AC. I have light coming in that room from 8am to 3pm so I’m just wondering if it’s too much direct sunlight. When my resintank is full or when I have a cartridge in, I usually have a towel over my printer too (looking for a better option to put on top btw )
And here’s for my hat-trick of replies…
Since I’m in Canada I cannot buy UV machine with the provided link. Is this one the same (looks the same but maybe there is a slight difference like the 405 wavelenght thingy or I dunno)
Thank again again again ag…!
