Printer Bed is arched/crooked  

Re: Printer Bed is arched/crooked

Here is how I would go about finding the cause of the warp. Make sure to take pictures as you go so you have them to send to support.

Check to see if the standoffs are still making contact between the Y carriage and the heatbed and there isn't anything stuck between the carriage and the heat bed forcing it up. Then check to see if the y-axis rod holders are cracked or out of place and that the screws are properly tightened.

Remove the metal sheet and see if the heated bed is level without out it. If the bed is heated bed is level without the sheet check underneath the bed to see if some of the magnets have come loose and fallen out.

Remove the heated bed being careful not to loose the standoffs/screws and place it on a flat surface to check for warping.

If you can't find the problem after these steps, contact support.

Re: Printer Bed is arched/crooked

After reading this message, I decided to check the flatness of my bed. I have had problems printing toward two of the edges and thought this might be the souce of the problem. Sure enough, the bed, with the print plate on, was not flat. I took off the plate and checked the heater board. The first few checks were dead on. Then I went across the center and found it high. I checked the corners and they were also off, It turns out that the screws are not flush with the surface of the heater bed. Looking at them, it appears that the countersink is too shallow. I also made sure the the screws were snug so no joy as a possible fix.

The only fix I know of is to pull the heater bed off and countersink the holes a bit more. What I don't know is how risky is it to do that?

Jerry

Re: Printer Bed is arched/crooked

After reading this message, I decided to check the flatness of my bed. I have had problems printing toward two of the edges and thought this might be the souce of the problem. Sure enough, the bed, with the print plate on, was not flat. I took off the plate and checked the heater board. The first few checks were dead on. Then I went across the center and found it high. I checked the corners and they were also off, It turns out that the screws are not flush with the surface of the heater bed. Looking at them, it appears that the countersink is too shallow. I also made sure the the screws were snug so no joy as a possible fix.

The only fix I know of is to pull the heater bed off and countersink the holes a bit more. What I don't know is how risky is it to do that?

Jerry

I would contact support before doing any drilling on the heater bed to see if they have suggestions or if it is bad enough for an RMA.

Re: Printer Bed is arched/crooked

Jerry & Ricardo:

Before countersinking or excessive screwing of the heatbed screws, here is something to check on the heatbed first if you want... Don't know if it is relevant, but it is easy to check.

When I was assembling my printer, I had a problem with a screw not going in all the way. What I did (inadvertently) was to take off the screws from the heat bed and run a zip tie up from the bottom of the heatbed out the top to help with getting the spacers in place easily. I got a "plug" which was the problem... It was removed and I continued without issue and have been printing ever since without problems. I would try all Y-axis Heatbed holes with a zip tie run up through the bottom to see if you have a similar issue. ( I posted a comment in the assembly instructions about this but you may not have seen it if you assembled before end of August).

It seems to me like a plug from the process of tapping the screw holes in the Y-axis was stuck or something. see attached picture. That would definitely prevent the screw from fully screwing in. It was inside the middle screw hole on the Y-axis and looks like a tap scrap thingy...

Re: Printer Bed is arched/crooked

Was the junk coming out of the heatbed or the carriage?

I did a quick check and there is no play in the heat bed and the all the outer spacers are snug. So, I'm thinking I proably don't have the problem but will tear down the heatbed assembly in a couple days to check for sure. If that checks OK, I think I will contact support.

I noticed that the side of the print plate that I always have down has deformations in the PEI where the screws are high. Probably not a big deal. but...

Jerry

Re: Printer Bed is arched/crooked

If the question was to me....

Heatbed. Step 16 of section 7 textile sleeve of the online Kit assembly instructions is where my comment is.

Yeah, I could not get my screw to screw in at all, but I could see where someone could force the screw in and it would not fully seat and cause a bump on the the heatbed which would cause a high spot.

regardless, the tension on the heatbed screws is important to bed being level ( in addition to other reasons for levelness).

Re: Printer Bed is arched/crooked

My bed gets warped once in a great while, it always comes down to something getting on the heatbed that I don't notice as I am sliding the PEI sheet on. Sometimes it's something rather solid, sometimes it's been something gooey. I have no clue where some of it comes from, but I can't argue it is there and must be remove to get a flat bed again.

Re: Printer Bed is arched/crooked

Thanks for the answers,
I'll also like Jerry the heating bed, the days, again dismantle and check everything, but at first glance, all screws are in it and also firmly.
I will also check the slide and the positions of the spacers. I suspect the mistake there.

@ bruce
Screws are all in there and fixed, there were no problems with it during installation. In the beginning, the mistake was even the other way around. So that my bed was deeper in the middle, now it has arched outwards.

@ jbinfl
I do not really recognize what you mean in your photos.

@ Tim
Clean your heating bed and your PEI shield on both sides with acetone.

Re: Printer Bed is arched/crooked

Hello,
I have my printer now 3 months, now once a week printed anything.
At my recent print I noticed that the first layer is very thin.
I then brewed and found that my pressure bed on the sides much further down.
It looks like my y-sled is completely spoiled.
Between left and right it is a height difference of 2-3mm. YES "mm"!!! please look the picture.
How can that be? Where does it come from? What can i do?
It did nothing fall on it, he stands in a housing.
In the photo he is hot, when it is cold, it is even more.

Hello Rocardo,
i had a warped bed after about 5-10 prints.
The carriage was absolutely flat, the spacers had axacly the same length und nothing between the Heatplate and the Steelsheet.
In my case it was just warped for no reason but quickly replaced by Prusa support.
That solved my problem 100%.
Greetings Kai

Re: Printer Bed is arched/crooked

@ Tim - Clean your heating bed and your PEI shield on both sides with acetone.

I do NOT have bed flatness issues. You do. I am only trying to describe something that might be causing your problem. I have seen the bed warped by debris that gets stuck to the fiberglass - not the metal sheet. Stuff falls on the printer bed when removing parts, and if you don't take care to dust/clean the fiberglass surface before setting the metal sheet, this stuff build up can causes problems.

I suspect, if you keep operating in the same way, you will begin having warping issues again, even with the new bed.

Re: Printer Bed is arched/crooked

I finally took the time to play with the heat bed screws not being level. I decided to see if they were small alignment problems with the screw holes so I loosened all 9 screws and then jiggled the heat bed. I then tightened the screws down a bit and jiggled again.

I repeated this process until all screws were finger tight. By that I mean I was holding the allen wrench between by thumb and index finger and rolling it so very lightly tightened. The heat bed was snug and jiggling was not possible.

I then reverted to the directions provided by Prusa to finish up the process.

I rechecked and two screws were a bit high so I tightened them just a bit more – less than 1/8 of a turn. The result was one screw was still slightly high but I was unwilling to apply any more torque.

I redid the calibration and so far, all is working well. I will recheck the bed in a few weeks just to make sure all is well.