New machine won't print

[mrjayd]

I assume then that when pressing the "Home" button, with the lock screws loosened, the trolley drops to a point and stops. If it does then the only possible problem is maladjustment of the platen. Try it again and press just very lightly on the platen when tightening the lock screws (front one first). Do not over-tighten the lock screws as that will cause the platen to shift position.

After manual alignment raise the platen by 0.1 mm and press the "Z=0" button. This sets a "logical" zero position at the current height when you press the button. G-Code printing commands for the platen to move to position "0" will move to this logical manually set "Z=0" position. The "Home" button will always move the platen to the hardware optical sensor controlled limit regardless of how the "Z=0" function is set.

A thought--what happens if you perform the alignment procedure, leave the paper (2 layers) in place, then  raise the platen 25 to 50 mm or so, and press the "Home" button once more? The platen should fall to where the paper is snug again, with no incident. If not I would begin to suspect an inconsistent or fouled optical sensor, or that the sensor "flag" on the bottom of the trolley is loose or fouled. Or that the trolley is set too tight on the rails and binding--when I disassembled my Mars to install the new mast i found it took 4.5 to 5.0 lbf to move the trolley--far too much I was able to adjust it to just 3 to 4 ounces. The Jackson mast requires zero force to move the trolley.

Z-axis sensor flag:

I also tried what you asked and went ahead and leveled again and raised it 50mm and hit home. It came all the way back down tight to the bottom and just starting humming again. No matter what I do it does this same thing every time.

[cliffyk]

With the build plate assembly and resin vat removed, and "Home" button pressed, does the z-axis trolley fall, stop; and then rise and fall a bit before it stops? Does it do that with no grinding or growling of the stepper motor.

If so the limit switch is working as it should. When in that furthest downward position, with the platen lock screws loose, and a sheet of paper to protect the LCD glass is it possible to compress the platen against the preload spring and mount the build plate assembly onto the trolley arm? IF not the trolley has descended too far indicating that the limit switch is defective, improperly mounted or connected to the mobo, or maladjusted.

[mrjayd]

With the build plate assembly and resin vat removed, and "Home" button pressed, does the z-axis trolley fall, stop; and then rise and fall a bit before it stops? Does it do that with no grinding or growling of the stepper motor.

If so the limit switch is working as it should. When in that furthest downward position, with the platen lock screws loose, and a sheet of paper to protect the LCD glass is it possible to compress the platen against the preload spring and mount the build plate assembly onto the trolley arm? IF not the trolley has descended too far indicating that the limit switch is defective, improperly mounted or connected to the mobo, or maladjusted.

Yes with the plate removed and when I hit home it goes all the way down and rises a bit and back down a bit with no grinding. It also does this with the plate on and the screws loose but as soon as I level and tighten the screws it just bottoms out and makes that noise when it comes down.

[cliffyk]

With the build plate assembly and resin vat removed, and "Home" button pressed, does the z-axis trolley fall, stop; and then rise and fall a bit before it stops? Does it do that with no grinding or growling of the stepper motor.

If so the limit switch is working as it should. When in that furthest downward position, with the platen lock screws loose, and a sheet of paper to protect the LCD glass is it possible to compress the platen against the preload spring and mount the build plate assembly onto the trolley arm? IF not the trolley has descended too far indicating that the limit switch is defective, improperly mounted or connected to the mobo, or maladjusted.

Yes with the plate removed and when I hit home it goes all the way down and rises a bit and back down a bit with no grinding. It also does this with the plate on and the screws loose but as soon as I level and tighten the screws it just bottoms out and makes that noise when it comes down.

Then platen must be shifting when you tighten the screws; try not tightening them as much, just "snug" them up. Do a test with something absurdly thick, like a piece of a beer carton, as a gauge.

[mrjayd]

With the build plate assembly and resin vat removed, and "Home" button pressed, does the z-axis trolley fall, stop; and then rise and fall a bit before it stops? Does it do that with no grinding or growling of the stepper motor.

If so the limit switch is working as it should. When in that furthest downward position, with the platen lock screws loose, and a sheet of paper to protect the LCD glass is it possible to compress the platen against the preload spring and mount the build plate assembly onto the trolley arm? IF not the trolley has descended too far indicating that the limit switch is defective, improperly mounted or connected to the mobo, or maladjusted.

Yes with the plate removed and when I hit home it goes all the way down and rises a bit and back down a bit with no grinding. It also does this with the plate on and the screws loose but as soon as I level and tighten the screws it just bottoms out and makes that noise when it comes down.

Then platen must be shifting when you tighten the screws; try not tightening them as much, just "snug" them up. Do a test with something absurdly thick, like a piece of a beer carton, as a gauge.

Same thing. I just used the whole little instruction book and I am not cranking down on the screws at all but I move the plate up 30mm and then come back down and it want to go all the way to the bottom and start growling. Not much else I can do but return it but this company just wont contact me back. I thought this was a respectable company.

[cliffyk]

Same thing. I just used the whole little instruction book and I am not cranking down on the screws at all but I move the plate up 30mm and then come back down and it want to go all the way to the bottom and start growling. Not much else I can do but return it but this company just wont contact me back. I thought this was a respectable company.

It's got to be that the limit switch is defective in some manner...

Your situation is why I nearly always buy things like this from Amazon--just tell them you don't like it, slap the label they give you on the box and away it goes--they'll ship another that you'll have in a day or two if that's what you want.

I am very cautious about eBay, and no longer use any of the Chinese outlets (Ali-Express, DX, etc.)--the prices may be attractive but is something goes wrong you will most likely be screwed. I have heard of MMF of course, but have never dealt with them. An unfortunate part of buying "the cheapest there is"--be it products service or a combination of the two-- is that very often you will get "the cheapest there is".

They have to not be doing something as well a the other guy in order to sell for less and still make a living...

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Re; your printer the only other thing that occurs to me is that the trolley is just too damned tight on the rails. As I said above mine was far too tight, it nearly popped out of my hand and flew across the room when I took it out of the mast. You should not have to do this on a new machine, and may not want to do it as you'll be sending it back, however it might be something to check if you are as stubborn as I about having things work as they should.

[mrjayd]

Same thing. I just used the whole little instruction book and I am not cranking down on the screws at all but I move the plate up 30mm and then come back down and it want to go all the way to the bottom and start growling. Not much else I can do but return it but this company just wont contact me back. I thought this was a respectable company.

It's got to be that the limit switch is defective in some manner...

Your situation is why I nearly always buy things like this from Amazon--just tell them you don't like it, slap the label they give you on the box and away it goes--they'll ship another that you'll have in a day or two if that's what you want.

I am very cautious about eBay, and no longer use any of the Chinese outlets (Ali-Express, DX, etc.)--the prices may be attractive but is something goes wrong you will most likely be screwed. I have heard of MMF of course, but have never dealt with them. An unfortunate part of buying "the cheapest there is"--be it products service or a combination of the two-- is that very often you will get "the cheapest there is". 

They have to not be doing something as well a the other guy in order to sell for less and still make a living...

----------------------------------------
Re; your printer the only other thing that occurs to me is that the trolley is just too damned tight on the rails. As I said above mine was far too tight, it nearly popped out of my hand and flew across the room when I took it out of the mast. You should not have to do this on a new machine, and may not want to do it as you'll be sending it back, however it might be something to check if you are as stubborn as I about having things work as they should.

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Same thing. I just used the whole little instruction book and I am not cranking down on the screws at all but I move the plate up 30mm and then come back down and it want to go all the way to the bottom and start growling. Not much else I can do but return it but this company just wont contact me back. I thought this was a respectable company.

It's got to be that the limit switch is defective in some manner...

Your situation is why I nearly always buy things like this from Amazon--just tell them you don't like it, slap the label they give you on the box and away it goes--they'll ship another that you'll have in a day or two if that's what you want.

I am very cautious about eBay, and no longer use any of the Chinese outlets (Ali-Express, DX, etc.)--the prices may be attractive but is something goes wrong you will most likely be screwed. I have heard of MMF of course, but have never dealt with them. An unfortunate part of buying "the cheapest there is"--be it products service or a combination of the two-- is that very often you will get "the cheapest there is". 

They have to not be doing something as well a the other guy in order to sell for less and still make a living...

----------------------------------------
Re; your printer the only other thing that occurs to me is that the trolley is just too damned tight on the rails. As I said above mine was far too tight, it nearly popped out of my hand and flew across the room when I took it out of the mast. You should not have to do this on a new machine, and may not want to do it as you'll be sending it back, however it might be something to check if you are as stubborn as I about having things work as they should.

Yeah I ALWAYS buy from Amazon. I just liked this green limited version from MMF. They must have a deal with Elegoo to be able to sell so cheap.

[Ryan Homer]

I have been having the same problem. After going through the whole manual step by step and adjusting the z-axis, it still is making that grinding sound when it goes into the resin. After looking at a bunch of other people's responses, it looks like it is a problem with adjusting the z-axis 0 and making sure the build plate is not pushing on the screen. My z-axis works moving up and down manually and is doing fine in all of the other aspects. I have even tried realigning the z-axis 0 two times now. The first time, I followed the manual and used a sheet of paper and made so that it is just tight enough that I can still pull the paper out. The second time, I followed some responses that I found online and moved it up about 1.5 mm (which is a lot). It is still making that sound and having that problem. This is a new Mars 2 Pro and I am just trying to print the Rook file that comes with the printer. Please help!