what am I doing wrong ??

[mighalpern]

Ok
so I got my photon out of the box and went thru with all the leveling and prep work as needed.
Its a sunny day and figured that i could get my first print cured by the sun.  I poured in my orange resin ( came with it ) and tried to print the test cube
after about 2 hours I could see the build plate had nothing attached 
so I rechecked everything and sent it printing again,  now at 33% and I can see nothing attached again.

I am using the defaults on the USB for the test cube.

where am I failing

thanks

Miguel

[Chris333]

Use a plastic spoon or something similar and dig around in the resun to see if you feel something stuck to the FEP film. It is possible it just didn't stick to the build plate and all of those layers are stuck to the film.

[mighalpern]

yup was stuck to FEP film.  drained out and put away for the night,  getting cold in the garage too.
Do you just wipe the film clean with a rag, or IPA it ???
I will try tomorrow once again.
the default setting are
layers  8
Exp off  1.0 sec
bottom exp  50 sec
normal exp 8 sec

does this sound normal. 
thanks Chris33

[Chris333]

Think I'm using higher times for the first few, but isn't the test cube pre-sliced? I've never even tried to print it.

[IronPenguin]

Be careful getting the cured resin off the fep. It's real easy to puncture. The method I use is to clean
 Vat with IPA, but leave a little in the vat, then push up gently from under the fep while carefully prying with my fingernail along the edge of the stuck piece. Don't use anything real sharp.

To your original problem, I'd bump the exposure for the bottom layers up to 60. Also, there are a lot of smaller test files out there that won't take as long. Personally I can't imagine printing anything that long as a test. I found a small cube on thingiverse that worked well. The Amerlab test file is good, too.

Hang in there. It really is a learning process, with failures a part of it.

[narrowminded]

Here's an old post on this topic.  I have never had a lost part with these settings.  I still use 115 seconds for 8 bottom layers which is probably on overkill but is only for eight layers and it is the platform that the whole part builds from.  I just figured that wasn't the place to save time. 

Clean the plate well with alcohol, shake the bottle very well or mix the resin already in the vat.  I use the spatula that came with the machine gently making sure to lift the resin from the bottom film.  Then on start up, cycle the build plate through the "Home" position to further afford some mixing action.  Again, might be overkill but it has worked reliably for me, 100% of the time.

https://www.therailwire.net/forum/index.php?topic=45969.msg603257#msg603257

There are many conversations on this topic that will show up with a search for "bottom layer cure times" and variants on that.

[John]

I had no problem with the test cube out of the box .... it should work correctly unless you have a leveling problem.  Go through the setup one more time .. make sure you are completely leveled .. if you arent hearing a pop sound when it lifts the print plate == then you aren't getting stick

 one other thing you need to watch is the temperature .. resin / room should be warmer than around 68F ...  make sure that you mix the resin good in the bottle by turning it ..

I also make the bottom layers cure longer per layer ..

[Chris333]

I'm using 115 seconds for my base layers.

[mighalpern]

ok tried a third time with the 115 seconds  on the bottom 8 layers, still stuck to the film instead of the plate.   
The garage is in the low 50's so I'll try again after one more re-level and gapping and then bring it into the house and see if that helps
 Its very weird that when i plug in the usb stick I find the cube file easy on the photon,  but its not readily visible when I plug the USB  in my laptop.   So I have downloaded the test cube stl. file and checked it in the slicer program and then placed it on the usb stick as cube #2  when I get home in the morning I'll plug it in and see what comes up.
thanks for the help guys

Happy New Year

[mighalpern]

Attempt #4 failed to adhere to the build plate.
I will take the machine to work this weekend, where it will be at about 65 degrees or more and then hopefully that's the key
Can someone please explain how to place Stl files  to the usb, more like where the hell is it on the USB directory wise.  Im having a suspicion that my stick might be corrupt or incomplete.

I placed an Stl file on another usb stick and the machine can not see it.

[Chris333]

Can you just bring it inside to test?

.stl files won't help you as the machine only reads .photon files. I just plug the USB into my computer and then drag the files to it. I did go through a bunch of USB sticks before I found one that would work in the machine. Funny everyone says the stick that comes with it is junk, but it is my best working stick out of all of them.

You put .stl files in the slicer software to make it into a .photon file.

[Chris333]

And I level my plate by using a sheet of paper as a spacer. Tighten till I can move the paper and them move up 1 from there.

[rodsup9000]

Tighten till I can move the paper and them move up 1 from there.

 I think Chris meant to say "till I can't move the paper" .

 Also, when I have it so the paper won't move and before I raise it .01mm is when I tighten the set screw on the build plate.

[mighalpern]

Thanks guys
Yes i will snug that sheet even tighter than I have done in the past.  I'll have it here at work over the weekend in the lab fume hood where its warm
And thanks for the clarification on the type of files chriss33

[mighalpern]

finally !!!   success  !!!  5th try
Its printing as I write,
 but its on the build plate.
 I went back and set the zero so that the paper could not move back in and needed a good effort to pull out.  I did find that my plate does not like to level evenly as it came delivered, laying it flat on the LCD and tightening the set screw would always leave the right side slightly raised.  I finally spun the plate 180 and then could tighten the plate perfectly flat.  perhaps  something on the gimble ball  or is not perfectly round

Anyway thanks to all for the help.