[Closed] trouble leveling the frame  

Re: trouble leveling the frame

Sounds a silly question.. is your table smoth?

Regards Joan

Re: trouble leveling the frame

It's a good question Joan I wasn't sure so I changed orientation and also switched to another surface and it's always the same corner.

Were you able to get yours flat without too much effort?

If I don't tighten the screws beyond the initial grab then it seems to be okay but i was worried that they'd shake loose over time.

thanks

Re: trouble leveling the frame

mine is just ok... ended up loosening all screws and re tightening them in increments until no discernable rock.

regards Joan

Re: trouble leveling the frame

Depending on the surface I also had one corner which was not perfect.
I tried a lot and then said „a fck it“:-)

I was in the end ok but not perfect.

Put some heavy books on the problematic half while assembling. Do one screw per extrusion at a time. Not all four.

Maybe change orientation of face plate. I heard from another member he changed his and his problem was gone!

Re: trouble leveling the frame

I have the same problem. One of the corner is about 1mm off the table (same result on every surface available in my appartment). I have tried loosening, applying some down-pressure, and re tightening them, to no avail. I was thinking about slightly enlarging some of the holes on the front and/or back plate to be able to better control the alignment but I'm afraid that I'll end up with even more problems down the line.

Re: trouble leveling the frame

Rotate (not flip) the extrusion 180 degrees and screw in place. Check to see if the extrusion is still not touching the table. This should tell you if the end of the extrusion is cut at right angles to two adjacent sides. Swap ends of the extrusion and try again.

You could try placing a shim under the extrusion top side to lower the extrusion downward.

Re: trouble leveling the frame

Thanks, that helped a lot (rotate 180 degrees). 😀
Before, I couldn't completely tighten any of the 8 screws on the front plane without warping.
After the rotation, I have slight warping (~0.3mm) if I tighten all 8. But I have no warping if I leave 2 screws loosely tightened.
I can live with that.

Re: trouble leveling the frame

Thanks everyone, the corner that i am having trouble with is the front right (the long extrusion).

I have tried:
- turning the extrusion around end to end
- rotating the extrusion 180 degrees (so top and bottom are swapped)
- swapping the left extrusion for the right extrusion
- adding a small bit of paper between the top of the front right extrusion and the z frame

None of the above seems to have any effect as soon as I tighten the screws. I'm going to see how I go if I don't tighten the screws as much. If I stop tightening almost immediately after it starts to bind against the z frame / plate then it seems passable. Basically i can still slip a piece of paper under the corner but it's not a massive gap and the sheet of paper encounters friction. After putting on the anti-vibration dampeners I can't notice any rocking.

Hopefully the screws don't shake loose but if they do maybe can I try some locktite. In addition, hopefully the slightly non square extrusion mounting doesn't affect the printing.

Cheers

Re: trouble leveling the frame

Have you tried to flip the front plate around?

Re: trouble leveling the frame

Thanks everyone, the corner that i am having trouble with is the front right (the long extrusion).

I have tried:
- turning the extrusion around end to end
- rotating the extrusion 180 degrees (so top and bottom are swapped)
- swapping the left extrusion for the right extrusion
- adding a small bit of paper between the top of the front right extrusion and the z frame

None of the above seems to have any effect as soon as I tighten the screws. I'm going to see how I go if I don't tighten the screws as much. If I stop tightening almost immediately after it starts to bind against the z frame / plate then it seems passable. Basically i can still slip a piece of paper under the corner but it's not a massive gap and the sheet of paper encounters friction. After putting on the anti-vibration dampeners I can't notice any rocking.

Hopefully the screws don't shake loose but if they do maybe can I try some locktite. In addition, hopefully the slightly non square extrusion mounting doesn't affect the printing.

Cheers

Wow, that's unfortunate. Hopefully your build table is flat. Your process should have uncovered something with the extrusion. I would think that the main metal frame would be flat but maybe not.

I have a granite surface plate at work so I will check my frame components when they come in just to see what they are like.

Re: trouble leveling the frame

I was having the same issues and tried rotating and changing extrusions and front plates, but there was always some twist in the frame.

What worked in the end was to use the extrusion orientation with the best reault, mount the long extrusions first with the front plate, getting that part level with the frame by putting a 1mm steel sheet under the low corner and pushing on the frame while tightening the screws, and then repeating the same procedure with the short extrusions.

It’s nearly perfect now, with a tiny amount of twist, you can barely feel it when pushing down the corner.

Re: trouble leveling the frame

Did you by any chance mount the rubber feet (to protect the table/surface building on) before tightening all screws? I had no problem leveling the frame itself but did cut the little knobs in the centre of the rubber feet away (opposite of where they screw in the frame) before mounting those.

Re: trouble leveling the frame

I have the same issue as mentioned above with the front right. I've tried swapping all the extrusions around as well as flipping the face plate, and have checked on a granite surface plate after seeing the issue on a table. Is it possible the square frame part is machined improperly or the powder coating is doing this? I ask as I've swapped extrusions around and face plates and the same (front long right) leg is a bit off the surface, and it's the same leg someone else mentioned.

I've tried all manners of tightening sequences and pressure while tightening with very little luck. I can slide 4-5 sheets of paper in the gap when not pressing down, I'll grab my feeler gauges later if an exact measurement is needed, and/or micrometer and try to figure out what's up with the frame.

I've moved forward with assembly but as this is my first printer have no idea how much this error will impact the printer. I'm hoping not significantly but I will want to figure this out and get it resolved, as this much error drives me nuts (have a CNC mill in the garage, I would never tolerate this lack of squareness). Is it to be expected? I'll contact support if nobody has any other ideas.

Re: trouble leveling the frame

Interesting, also on my frame it was the front right corner that always was a little high, even with changing part orientations.
The twist always seemed to get larger when tightening the screws, and I tried different sequences as well.
Keeping pressure on the frame on a flat surface during itghtening also didn's solve it.

But putting a steel sheet under the low corner and pushing the frame down during tightening did.
Basically I introduced a counter-twist that compensated the "natural" twist.

Frame ist straight and stiff, and I am confident it will stay that way.

Not perfect in terms of mechanical engineering, but totally adequate for this printer.

Re: trouble leveling the frame

Interesting, also on my frame it was the front right corner that always was a little high, even with changing part orientations.
The twist always seemed to get larger when tightening the screws, and I tried different sequences as well.
Keeping pressure on the frame on a flat surface during itghtening also didn's solve it.

But putting a steel sheet under the low corner and pushing the frame down during tightening did.
Basically I introduced a counter-twist that compensated the "natural" twist.

Frame ist straight and stiff, and I am confident it will stay that way.

Not perfect in terms of mechanical engineering, but totally adequate for this printer.

Which was the "low corner" for you? I had tried this method using the back right (short) and it didn't fix the problem.

Re: trouble leveling the frame

The front left corner was the low one.
But not too much, maybe 1mm or even less.

I hope in the next deign revision there will be one extrusion, not the split design with short/long offset sections. That should eliminate any such issues.

Re: trouble leveling the frame

Spent over 5 hours trying to do all the different ways... turn around, turn 90-180 degress, turn the front rear end...all are not working....I guess glass surface is reliable right? Tried all the flat surfaces I have and same result ~0.5-1mm gap my corner is the right near you if look at Prusa logo vs the left corner behind Prusa logo.

Im not sure if this is a design issue... but at least, if there could be some guidance or tolerance...watch all the youtube mk3 build video..My first time building as well so will be very frustated if end up having printing issues because of this.

Re: trouble leveling the frame

Spent over 5 hours trying to do all the different ways... turn around, turn 90-180 degress, turn the front rear end...all are not working....I guess glass surface is reliable right? Tried all the flat surfaces I have and same result ~0.5-1mm gap my corner is the right near you if look at Prusa logo vs the left corner behind Prusa logo.

Im not sure if this is a design issue... but at least, if there could be some guidance or tolerance...watch all the youtube mk3 build video..My first time building as well so will be very frustated if end up having printing issues because of this.

I'm honestly not so sure it's a big deal and my guess is that the extrusions weren't cut exactly square, in my experience they rarely are and part cost goes up exponentially as machine tolerances decrease. The overall length of the unit looks to be at least 325mm so 1mm out isn't too bad. If it really bothers you you could probably take the extrusions to a machine shop and have them face off the ends though you'd want to make sure to stay within the +/- 0.15mm length tolerance of the extrusions...

https://github.com/prusa3d/Original-Prusa-i3/blob/MK3/Frame/Extrusions.pdf

Re: trouble leveling the frame

@edward.c6

Haha! May be just because of the thinking 'perfect 1st build' and I was just starting? I was in manufacturing parts for oilrig and we have things 3-5m with +-1mm tolerace so I thought to print 0.01 then 1mm tolerace may be too much? 😆 😆

Either way... I have continue building adn leave it there... I guess I still can go back and adjust mid way if I found it would effect the print...
Hope to see somebody says that this - unleveling 1mm gap wont effect the printer functionality