Chamber temperature  

RE: Chamber temperature

Hello.

I'm currently modifying my Core One for this purpose so I can get the chamber temperature above 50 degrees.

https://www.printables.com/model/1638476-prusa-core-one-hightemp-450-modification-for-britt

Right now, I’m trying to move the Loveboard to the outside, cool/protect the NEMAs, and add some kind of insulation so the heat stays inside better.

I think you’d need to insulate and/or heat the chamber to get a higher temperature. Which, of course, causes the side effects mentioned above.

RE: Chamber temperature

There will also be a change in belt tension -- the belts actually contract at higher temperatures. Not sure how significant that is for print quality or lifetime of the various bearings; but for ideal settings one would have to readjust (relax) the belt tension somewhat when running high chamber temperatures.

RE: Chamber temperature

There will also be a change in belt tension -- the belts actually contract at higher temperatures. Not sure how significant that is for print quality or lifetime of the various bearings; but for ideal settings one would have to readjust (relax) the belt tension somewhat when running high chamber temperatures.

That's exactly what I want to find out: what happens to the printed object when the chamber prints at temperature “xy” for a while. So not 40 or 50 degrees—no, 60 degrees and up.

RE:

Posted by: @jan-d-slay

That's exactly what I want to find out: what happens to the printed object when the chamber prints at temperature “xy” for a while. So not 40 or 50 degrees—no, 60 degrees and up.

The new firmware 6.5.3 has made changes to chamber temperature management. The max has been lowered from 70° to 60°. When you hit 60° a warning dialog will appear and when you hit 65° (used to be 75°) the printer will purposely crash out with an over-temp alarm. Also, once the chamber goes over 55° the fans will cut on in an attempt to lower it. 

Seems Prusa is getting stricter about running a hot chamber on the Core One. 

What's even more interesting is why this isn't in the release notes...

RE: Chamber temperature

A temporary solution would be to move the temperature sensor for the chamber further down. That worked for my Core One as well. A difference of 10 to 15 degrees is achievable.

RE:

Posted by: @jan-d-slay

A temporary solution would be to move the temperature sensor for the chamber further down. That worked for my Core One as well. A difference of 10 to 15 degrees is achievable.

I guess the real question though is how long can the love board electronics, motors and lubricant handle being above 60°.

Also, and I'm wildly speculating, but maybe Prusa lowered it but didn't document it in the release notes because they are preparing to release an actively heated chamber kit for the Core One. Otherwise, why wouldn't they mention a significant change like this unless maybe they thought most people wouldn't notice anyway? 

RE: Chamber temperature

I have tuned my printer with the chamber at about 35 degrees. 

RE: Chamber temperature

I'm currently planning a modification where Fan 1 will be responsible for heating and Fan 2 for ventilation. I've already had Claude customize the firmware. I've raised the temperature limit to 80 degrees for testing purposes. I still need to install the mounts and connect the wiring.

I'll keep you posted.

RE: Chamber temperature

If you are willing to sacrifice your C1 for the benefit of mankind then I applaud this. However, I suspect the motors and electronics will fry out. Also the buddy camera can handle more than 55°. It shuts down after that. 

RE: Chamber temperature

I printed for 27 hours straight at 60 degrees without any issues with the camera(or anyhting else for that matter, no fans running on the older firmware), so its not an inherent feature. Its bothering to hear that they limited the chamber temp in the new firmware. Even without my chamber heater in std form it could reach 58degrees when printing with high bed temp and a sheet on the top. I seem to have decent layer adhesion with PPACF, but more would be nice for PPS for sure. With electronics lifetime its about time and temperature, i wouldnt be worried running slightly over normal(60ish) once in a while. But if I utilised max chamber temp all the time I would be more conservative.

RE: Chamber temperature

If you are willing to sacrifice your C1 for the benefit of mankind then I applaud this.

That’s a fitting description. I just want to see what happens when a Core One is pushed to its limits.

RE: Chamber temperature

Once, I left my Creality heater on by mistake and one of my prints went for like 3-4 hours above 70C, reaching 72-73 degrees when I realized and dialed it down. My C1 internals are all PC, PCCF and a bit of ABS, so not PETG inside. I did not have any issues whatsoever, but constantly it would push your luck for sure. If they limit the chamber temp this much, I will modify the firmware for sure. Also true for the INDX max temp. If it remains 300C, I would test it with 320 for sure, as it is usually a number materials can require. I understand the safety aspect of it though.

RE: Chamber temperature

I understand the safety aspect of it though.

Of course, I understand that too. Hot components and heaters that get very hot are obviously no joke. Besides, not every Prusa customer is the same. I know what I’m doing, and I know exactly what I mean when I say I want to push the limits of what’s technically possible.... The fact that Prusa sets certain limits here is perfectly normal from the perspective of reliability and durability.

RE: Chamber temperature

It’s interesting that Prusa has lowered the temperature. 
I’ve also fitted a Heater in my Core One. But mainly to ensure it reaches 55 degrees and maintains a constant temperature throughout the entire print.
In exceptional cases, I’ll go up to 60 degrees. The C1 won’t be able to handle much more than that in the long run.
When you see the effort required to handle temperatures above 70 degrees, it must be clear that a standard printer won’t last long under such conditions and will also struggle with printing issu

RE: Chamber temperature

Posted by: @rainer-2

It’s interesting that Prusa has lowered the temperature. 
I’ve also fitted a Heater in my Core One. But mainly to ensure it reaches 55 degrees and maintains a constant temperature throughout the entire print.
In exceptional cases, I’ll go up to 60 degrees. The C1 won’t be able to handle much more than that in the long run.
When you see the effort required to handle temperatures above 70 degrees, it must be clear that a standard printer won’t last long under such conditions and will also struggle with printing issu

Even 50° is enough. The problem with maintaining that temperature passively just using the print bed means the bed has to run hot at 115-120°. This causes a huge temperature differential between bottom layers of the print and the top of the print. The result is warping. If you can actively heat the chamber at a 55° you can also run the bed at 55° essentially eliminating this problem. 

RE: Chamber temperature

Posted by: @hyiger

 

Posted by: @rainer-2

It’s interesting that Prusa has lowered the temperature. 
I’ve also fitted a Heater in my Core One. But mainly to ensure it reaches 55 degrees and maintains a constant temperature throughout the entire print.
In exceptional cases, I’ll go up to 60 degrees. The C1 won’t be able to handle much more than that in the long run.
When you see the effort required to handle temperatures above 70 degrees, it must be clear that a standard printer won’t last long under such conditions and will also struggle with printing issu

Even 50° is enough. The problem with maintaining that temperature passively just using the print bed means the bed has to run hot at 115-120°. This causes a huge temperature differential between bottom layers of the print and the top of the print. The result is warping. If you can actively heat the chamber at a 55° you can also run the bed at 55° essentially eliminating this problem. 

That’s exactly how it is. With the heater, I can select the optimal settings for printing and don’t have to worry about the bed temperature to reach the chamber temperature. Even if the printer is in a room that’s only 15 degrees, the heater helps enormously.

I’m curious to see if Prusa will release an upgrade for this.

With my version, it would be simple. Just swap the left panel and plug it in.

Prusa could, of course, have integrated the controls into the firmware in other ways.

I’m happy with my solution. Of course, it works without it. But it makes life easier, and I enjoy implementing projects like this.

RE: Chamber temperature

There are a couple issues with electronics and mechanical moving parts and high temperatures. 

The first may be the max allowable temp of some components may be reached and they may fail. Some components exhibit a runaway failure, conducting more at high temps, such that they get hotter and hotter till they fail.

The second is the Arrhenius equation. For many components and things like lubricants, for each 10 degrees C the temperature goes up, the lifespan goes down by 1/2. So, you can shorten the life of components drastically. A 20 C increase can result in 1/4 the life. So, you may not have instant failures, but things won't last long.

Regards,

Mark

RE: Chamber temperature

It can be worse than you think for things already dissipating power. Let's say a motor is designed for and normally operates at a 60 C temperature rise. Maybe it has class B insulation rated for 130 C. Put it in a 70 C chamber and you've hit the maximum. Same with semiconductors. They have a derating curve and you can quickly get to the maximum die temperatures in a much cooler external environment than you might first expect. Now, you can buy 180 C motors and they aren't even that expensive. The semiconductor problem is more difficult and better heat sinking or even getting a thermal connection to the outside world might be necessary. An upgraded load cell is also needed.

RE: Chamber temperature

Some people might think I'm crazy or wonder if I'm trying to "ruin" my C1, but I'm currently working on a modified firmware that controls an external heater and regulates the chamber temperature. The first step will be to see how stable everything runs when printing at temperatures above 60 degrees. A powerful cooling system is also installed and will be tested at the same time.