Tramming/Leveling the bed

[HouseMonster]

Do you guys tram/level the bed cold or while the bed is heated? I watched the one online video and the guy mentions in brief he did it while hot. I wanted to know if you guys all did this. If not did you see any difference in print.

[detroitus]

I level mine at 80C. If you do it cold it can end up all wonky due to thermal expansion when it's heated.

[Alex M.]

When we first received our printer we checked it cold, it was perfect! Then we started printing and had all kinds of issues. We finally checked the bed when it was warm and found it was WAY OFF. So we adjusted it at 60 deg C and things were good until we started printing PETG and had the bed at 80 deg C. Checked the bed at 60 deg C and it was fine but at 80 deg C it was off again.

We have found that you must adjust it per bed temperature.

[Vice Chief]

I'm the guy who suggests doing it hot. I still suggest it because the shape changes as it heats up.

[MDVolle]

I have to agree with Vice Chief - I run a quick check at temp when I change filament types - especially when moving from one extreme to another.

I am not sure if there is an answer to this - I have a friend who is very engaged in the heat treating and tempering of aluminum for what he does (which has to retain exact machined tolerances for many years) and these aren't ideal conditions for keeping something flat. For him, Standard MIC6 or 6061-t6 is too "dynamic" and loses tolerance over a few years - it can be perfect when machined and just sitting on a shelf, three years later it won't pass inspection - so he had to generate a custom process to meet the need.

I though that having the bed stress relieved might make it stay once and for all but with our thermal cycling, it isn't guaranteed -

If anyone stumbles on a magic solution, I would sure be interested.

[HouseMonster]

When we first received our printer we checked it cold, it was perfect! Then we started printing and had all kinds of issues. We finally checked the bed when it was warm and found it was WAY OFF. So we adjusted it at 60 deg C and things were good until we started printing PETG and had the bed at 80 deg C. Checked the bed at 60 deg C and it was fine but at 80 deg C it was off again.

We have found that you must adjust it per bed temperature.

Thats what i'm afraid of. For large prints I want to print in PLA. But i want to use the enclosure to print things at PETG and Nylon. Maybe with those being small prints it should be fine. I'm tramming the plate now hot. But its a son of a B to get all right and even. Once one is adjusted and doing another it throws everything off. I know its the nature of it all but theres just got to be an easier way compared to my other printers. You would think with a 6k printer you get some auto bed leveling or auto adjusting when printing.

[MDVolle]

House Monster,

I have an N2+ Dual - I'm not sure what machine you have -

There have been numerous threads here on the site with possible modifications to the bed mounting - I created my own slightly different solution with springs and NyLoc nuts - no allen screws -

Mine had 9 long screws with two allen screws next to each position -

Now I am just using 9 slightly longer screws with springs and the NyLoc nuts on them. I put a thin brass strip on top of the spring so the spring couldn't cut into the heater and so if I wanted to add back in the allen screws, they would also press on the brass strip - not the heater circuit.

The springs are compressed enough that unless I start printing lead or stone, they are providing more than enough force to hold the bed up tight against the nuts.

The bed still has a few little low spots but in general, its been flatter and easier to adjust. If I am printing parts with a 0.10mm first layer, I have to pick one of the flattest spots but a 0.20mm first layer seems to work over most of the bed.

The three opposing screws within a little more than an inch probably causes some of the crazy changes with temperature - as the screws and the plate expand at different rates and can generate some significant forces - Once my plate was on springs, it actually has a LOT less response to changes in the temperature - the original "triple point" arrangement was very "dramatic" (best word fit I could think of for ^&*%#$%^%^ frustrating)

The nylon tips on my original allen screws had almost all failed - probably from doing a lot of printing in Nylon at 105C bed temp.

Do check out some of the other threads on this topic - there were a lot of thoughts -

You may also want to look and make sure that the bed height stop adjusting screw is tight - Mine was a little wobbly and that was causing all sorts of issues - I actually replaced it with a micrometer - I can measure the thickness of a skirt pass or a brim and just dial in the correction to my exact first layer height -

Having a "Happy" bed makes the printer seem so much "better" -

[Alex M.]

Totally agree with MDVolle about the bed modifications. I think this thread is very helpful: viewtopic.php?f=4&t=21

We first did a 5 point spring system but still had some issue. We have since moved to a 9 spring system and haven't adjusted the bed level since we first leveled it. I've printed some large (9" diam) parts without issues. I also found that a little hot glue to hold the z limit switch to the board really helped the consistency of the z homing.