Hi there,
This is my first post so I recently got the S3D software but I would like to know if it doesn't stop the fans when the enclosure reaches 50 degrees. The reason I ask is because the dreamer turns on its fans to make sure that the enclosure doesn't get too hot. It has a build in thermometer to seee what the enclosure temperature is and activates the fans if it's too hot. I just wanted to know if this is separate from the g code or is part of the flash print software. If it is part of the g code how can I set the fan on only when the enclosure is above 50 degrees? Is there a setting or codes to do that? As I know abs needs to be in a warm environment and I don't want the fans spinning if it doesn't need to as this could cause cracking in the print.
thank you for reading and I hope someone can help me
The fans on the back are there for safety reasons. They prevent the FlashForge Dreamer from overheating. You are lucky you have them.
I purchased an older FlashForge Dreamer, the one with the foggy door which did not come with fans on the back. It overheated a few times, and melted the X-carriage, making the printer useless until a new X-carriage was put in. To prevent this, I added my own external fans. I actually added 4. I have them controlled by my own thermostat. I set it to 50 C. The reason I use 50 C is for 2 reasons: 1) a lot of electric components are not rated much above 60 C; 2) If PLA is in the printer, it will get soft if the internal temperature reaches 55-60 C.
As you probably noticed, the standard G-code fan control in the Dreamer only turns on the active cooling fan for the extruders.
While my Dreamer is old hardware, its firmware is the newest available. I have looked at the firmware settings, I have looked at all the published FlashForge Dreamer G-code, and I see nothing present that lets you configure the temperature that turns on the external cooling fans. All I can see is that the firmware has a readout that shows what the internal temperature reads (this is always 255C on my Dreamer because it has no sensor for this), but no way to set the temperature that turns on the external fans.
Note that I mentioned that some electric components are not rated much above 60 C. I'm not sure why this is, but it seems pretty common. I don't know what the Dreamer's build chamber parts upper temperature limit is. The Dreamer might have some parts that can't exceed this temperature, I don't know. But most likely, they set the fan temperature to 50 C to prevent PLA from softening. A lot of people might have ABS in 1 spool holder and PLA in the other while printing ABS. If printing ABS and the internal build chamber temperature gets to about 60 C, then the PLA spool will get damaged. I imagine that will generate a lot of complaints from users.
Actually, there are cases where having the fans on 100% of the time is beneficial to the print, especially when printing very small prints with tiny details. It would be nice if FlashForge would expose a lower and upper limit for the fans to turn on. I can see valid reasons for not allowing this to go above 50 C, but there's no reason not to allow you to lower it. It would be nice if you could set it at 0 C so the fans are always on.
On my customized system, I can set my thermostat's on or off temperature manually.
When printing PLA, I have them on 100% of the time. There's no reason to turn them off. They improve small details and have no detrimental effect on the entire print that I can see.
When printing very small parts in ABS, I have the fans on 100% of the time. If not, the printed small ABS parts look melted, because layers are being printed on top of non-solid layers. You could slow down printing to prevent help this, but using fans works better.
When printing larger parts in ABS, I usually have the fans set to turn on at 50 C if I'm experiencing corner lifting on my print. If not, I leave the fans on 100% of the time.
THERE IS A POTENTIAL PROBLEM WHEN USING FANS THAT ARE CONSTANTLY TURNING ON AND OFF. This introduces banding in the ABS print. If you print a tall thin tower, you can see in the tower a band that's very slightly thinner where the fans turned on, and then its back to normal when they turn back off. It is very noticeable for thin towers. For other shapes, you might not notice it at all. But for towers, it ruins them. So if I'm printing tall thin towers, I set the fans on 100% of the time if possible.
As you mention onlylittlemike, there is a potential that the sudden on state of the fans could cause a crack to occur in a very large ABS print. I have not seen this happen however. Maybe I've just been lucky.
It would be great if the external fans were speed controlled, starting very slowly, and then going faster as needed. This would limit noticeable banding effects and limit the possibility of cracks in very large ABS prints. But thermostat speed control requires much more complex circuits than a simple on/off thermostat needs.
so I recently got the S3D software but I would like to know if it doesn't stop the fans when the enclosure reaches 50 degrees. The reason I ask is because the dreamer turns on its fans to make sure that the enclosure doesn't get too hot. It has a build in thermometer to seee what the enclosure temperature is and activates the fans if it's too hot. I just wanted to know if this is separate from the g code or is part of the flash print software. If it is part of the g code how can I set the fan on only when the enclosure is above 50 degrees? Is there a setting or codes to do that? As I know abs needs to be in a warm environment and I don't want the fans spinning if it doesn't need to as this could cause cracking in the print.
