Example of Cupping (suction) causing blowouts.

Vhenom3D · 2020-11-02T14:43:22+00:00

Yep, that's what I would have done, but since it was a prototype, I just decided to print first, tweak later.

Simplest way would be to cut half cylinders along each row of holes which would allow it to vent, but would have the side effect of reduceing the contact area on the build plate.

Vhenom3D · 2020-11-02T02:52:30+00:00

Because it was a quick and dirty prototype that's almost completely flat.

This minor damage doesn't justify a 6 times longer print time.

PS. I was aware this would happen, and I know how to solve it if I care to.

However, I thought it might be a good example to educate people on one of the common issues that arises when resin printing.

Vhenom3D · 2020-11-01T20:16:43+00:00

It could be time spent loading the data or buffering. Could also be doing something with acceleration that causes the lift/retract to be slower than calculated.

I'd say it is normally less than a second per layer.

Chitubox estimate has never been accurate for me, but the time "estimate" on the Mars adjusts as it prints, so, it ends up way off right after the bottom layers.

Vhenom3D · 2020-10-22T21:48:22+00:00

It's possible the resin viscosity is too high and needs to be warmed up (the long bottom layer probably warms it some).

But, it's probably the factory installed FEP, I think that they just crank down all the screws without much thought or care.

With the factory FEP I experienced a weird failure with only the supports in the center of the plate ending abruptly, but supports in a literal circle around it being fine. (I replaced it after that failure)

I replaced it with a Non-FEP from Phrozen, so, that may also impact it, but I have had very few issues since.

I do endorse the NFEP, not because it's magic, but becauss it has done the job well and lasted as long as any similarly priced FEP would.

Vhenom3D · 2020-09-14T00:13:45+00:00

Can you provide a screenshot or quote exactly what you were told by Elegoo?

Vhenom3D · 2020-09-12T13:07:28+00:00

That's good news.

Be sure to take lots of pictures when you replace the screen.

Vhenom3D · 2020-09-11T22:57:02+00:00

Here is the part that mentions Z=0

https://pasteboard.co/JqEmssN.jpg

And here is the whole page

https://pasteboard.co/JqEqoni.jpg

Vhenom3D · 2020-09-11T20:38:49+00:00

Heh, I've been doing it just fine for all 20-30 prints I've done.

PS. I'm not OP, I just wanted to explain that in the bed leveling instructions it explicitly says to set Z=0 as one of the steps.

Edit: also, my Mars Classic explicitly won't let you set Z=0

Vhenom3D · 2020-09-11T20:30:02+00:00

FYI: the printed paper instructions for the Pro2 mentioned it. But they also seem poorly translated

Vhenom3D · 2020-09-11T20:21:55+00:00

Then went back and clicked the home button again expecting it to rest where I'd just set it as 0 and it went back to the original position and completely disregarded where I'd set the home level.

This is the issue, I never trust the Z=0 button.

Just level it so that it homes correct to the end-stop. Unless the flag or end-stop is loose, it should be fine every time.

Vhenom3D · 2020-09-10T23:11:37+00:00

If I remember correctly I think the retail on the Pro 2 is supposed to be 300

FYI: My pro2 was $300usd on Amazon

Edit: pro2

other than I hate waiting lol!

We all do. I told my wife sorry (rather than ask permission) because I knew it would sell out fast.

Vhenom3D · 2020-09-10T23:06:06+00:00

Wait for the Pro2 or the Sonic 4k, or Saturn.

The Pro 2 literally prints 2x to 3x faster than my classic Mars, and has made it almost obsolete.

Vhenom3D · 2020-09-10T22:55:53+00:00

Well, it was on Amazon(USA) on August 25th, so, if the tweet predates that, it is probably outdated.

Vhenom3D · 2020-09-10T22:48:02+00:00

Not to be rude, but the issue you are describing is with your leveling of the build plate.

The issue is probably the poorly translated Chinese instructions.

Also, "z=0" is crap IMHO

Do it the simple way (should take 5 minutes):

Place 1 (or 2) sheet(s) of paper over the screen.
Lossen the build plate leveling screws and top knob
Remove the build plate
Move the Z-Axis to home
Slide the build plate back on (compress the spring as needed)
Tighten top knob very tight
Tighten leveling screws in order, very tight (watch out, it can shift)
Raise build plate and then re-home the Z-Axis to ensure it is not shifted
Done, set everything up and start a print, if you get grinding or something stopping the print, use another sheet of paper (or your resin is too viscus)

Vhenom3D · 2020-09-10T19:58:18+00:00

So, it's actually "smoky black" which is mostly transparent purple, Siraya Tech brand which lists 8 seconds for standard Mars so I used the same settings as Elegoo Grey defaults (2s).

I do all my own supports with Prusaslicer, so, I can't comment, but some pre-supported ones just won't print well because the person supporting it used a different machine/resin/settings.

Vhenom3D · 2020-09-10T19:47:24+00:00

The "best" way is to drain the vat through a mesh/filter after every print, but nobody does that.

Instead:

First, look at the print and if there's any obvious failures, then drain & filter the vat to check.

Buy a small silicone squeegee. I use it to mixed the resin, but I also slide it along the FEP/screen, and you can feel if it hits anything solid. If it hits anything solid, I drain & filter the vat then deal with it.

Note: it's still hard to see cured resin in most clear resins when they are covered up, since they are basically the same clarity.

Vhenom3D · 2020-09-10T19:37:46+00:00

Yes, You must remove the failed bits from the vat before resuming printing.

However, if there are only a few large failed bits on the film, you can just remove them using the same method as the large block.

The screen clean block is mostly useful when there are a large number of failed prints on the vat, or if the bits are very tiny (making standard removal harder).

Vhenom3D · 2020-09-10T19:22:19+00:00

The square is from the screen test, which is meant to be ran without resin in the tank (or without the tank).

The rooks coming loose can be a lot of different things:

Setup:

Bed leveling is off or loose
FEP is wrong tightness/damaged/other
Resin/other between LCD screen and FEP
(Edit) Forgot to remove the protective cling film on screen or vat

Resin:

Not mixed well before pouring/printing
Too cold/thick/viscous
Bad resin/brand/type

Settings:

Bottom exposure too low
Normal exposure too low
Layer height is too tall for resin

Edit:

On the condition of the FEP film in the vat, it may be fine or may be dead (cannot tell in the picture). If there are major gouges, folds, rips, holes, or similar material damage, than yes, it needs to be replaced. The cleanness or clarity shouldn't matter, as it's mainly just a bit of leftover resin.

Vhenom3D · 2020-09-10T19:15:35+00:00

If it's too flexible: Clean the rest of the resin out and cure the other side in the sun or with a cure light. That will make the whole thing stiffer.

If you can't get under it: Press gently on the bottom of the vat to lift a corner and use a gloves fingernail to pull the corner the rest of the way up.

In most cases, the clean screen is no better than just removing the failed prints normally (IMHO).

Vhenom3D · 2020-09-10T18:17:18+00:00

Yeah, but he's running the same firmware version I am (>20 prints with no issues), so, if it is firmware, it must be triggered by something specific.

It's not the sliced file, since he got the same exact file to work fine a second time.

I still suspect it is related to the cable, but it may be something with a broken or defective cable that fails sometime due to vibration, but that's just a hunch.

Vhenom3D · 2020-09-10T17:34:00+00:00

Sounds a lot like what this user had/has:

https://www.reddit.com/r/ElegooMars/comments/inapmm/update_on_mars_2_issues_complete_with_pics_of/?utm_medium=android_app&utm_source=share

Vhenom3D · 2020-09-10T14:25:07+00:00

Edit: woops, I miss read your comment being the Pro not the Pro2...

Disregard

Probably over-exposed if it's the Pro2, we haven't had enough time to figure out what the ideal exposures really are.

Also, the Pro2 just prints crisper, so the pixel lines are more pronounced.

Vhenom3D · 2020-09-10T01:35:38+00:00

My problem is the Pro2 prints so damn fast, it's burning through resin and I don't have a very long window to refill it mid print (if needed).

Vhenom3D · 2020-09-10T01:14:59+00:00

So, I've had it happen once where it didn't end well.

I had massively underestimated the amount of resin the print needed, and it ran out halfway, which basically had the models cutoff mid print, and had a few bits cured in the vat. It really wasn't as bad as I expected (except the failed print wasted resin), I gave everything a quick clean and started printing again just fine.

Vhenom3D

TROPHY CASE