I did chamber heating tests with a Nevermore and Elis bed heating fans to see how fast different setups heated up the chamber. Results inside!

[Poisson]

I installed a V5 Duo V2 (Normal sized) Nevermore and 2 bed fans using the Elis bed fan mount for air filtering and speeding up the chamber heat up times. But how much did it really help? Since I apparently have too much time on my hands and nothing to print at the moment, I tested various combinations of these configurations to see how fast it heated up the chamber.

Here is my setup:

Voron 2.4r2 350 built from a formbot kit (now with many mods)

2x bed fans

The fans in the Nevermore and the bed fans are all GDSTIME 5015 12V GDB5015.

My chamber thermistor is sitting in a modified Z_chain_guide stl which has a slot for a thermistor to sit in it. This means my chamber temperature readings are being taken from the rear of the chamber, at whatever height I have my Z set at. For these tests I picked somewhere near the middle at 175mm. Is this the best place to take readings from for this test? Who knows. I figured somewhere near the middle was close enough for what I was trying to accomplish.

I have my home assistant instance taking data from Moonraker, logging that into InfluxDB and graphing with Grafana.

I was not able to get the exact same start temperature the entire time, but kept it within a few degrees, so not a completely scientific test but I feel close enough to draw conclusions.

The bed is running at 110C I used the fan configs in the Elis bed fan github to control the fans. For the Nevermore during bed heating it runs the fans at 40% and then 100% when the bed reaches 110C. For the bed fans it run the fans at 20% during bed heating, then at 60% when it reaches 110C

Ambient temperature in the room stayed about 1 degree from the what it started it when I began doing testing. Between 15C and 16C.

Here are the results:

To start I did tests with neither the Nevermore nor the bed fans running:

Test 1:

No fans running. No Exhaust fun running. Chamber being heated by the bed alone.

32 minutes from start till 30C
34.2C after 1 hour

 

Test 2:

Only exhaust fan running. Ran from the beginning of the test at 100% and the entire time.

47 minutes start to 30C
31.2C after 1 hour

 

Here is where I started using the Nevermore and bed fans.

Test 3:

Nevermore only. Using the fan curve I listed above

22 minutes start till 30C
38.3C after 1 hour

 

Test 4:

Nevermore with exhaust fan running.

26 minutes start till 30C
35.2C after 1 hour

 

Test 5:

Nevermore and bed fans using fan curve listed above.

30C after 19 Minutes
43.2C after 1 hour

 

Test 6:

Nevermore, bed fans, and exhaust fan running.

30C after 19 - 20 minutes
40.1C after 1 hour

 

So what conclusions can we draw from this? 1. Don't run your exhaust fan during your heatsoak sequence, every single configuration it increased warmup times, though with both the Nevermore and the bed fans running it wasn't enough to make a big difference. 2. A Nevermore alone helps noticeable with heatup times, but a couple bed fans will help a little more.

Things I should have tested but didn't: Running the test with just the hotend fan running and nothing else to see how much that helped with heating the chamber. However for this to really be efficient, I would need the hotend down low to the bed to help push more hot air around, thus lowering my z, thus invaliding comparing that to the other tests (since my chamber thermistor is in z chain guide, which is attached to the rear gantry). Readings from lower to the bed are going to be much higher than at 175mm.

The other thing I don't feel great about is that the Nevermore pulls air from the rear, under the bed, and pushes it up the front. The bed fans pull air from the front, and push it under the bed towards the back. I feel like this is cycling more air around the bottom of the chamber and not pushing it around the whole chamber as efficiently. Ideally I should mount the bed fans somewhere near the back so they are also pushing from the back to the front, however I have a decontaminator bucket one one side of the rear and I haven't thought of a good way to set this up yet. 

Edited November 23, 2022 by Poisson

[mvdveer]

Great work and a very helpful analysis. Thank you for the effort you put into this.

[smirk]

Definitely a good analysis.

[Demosth]

This is great! Thank you so much for sharing and doing the work!

I didn't see in mentioned, is your ambient temperature consistent?

[Poisson]

46 minutes ago, Demosth said:

This is great! Thank you so much for sharing and doing the work!

I didn't see in mentioned, is your ambient temperature consistent?

The ambient temperature for the room? It stayed between 15C and 16C for the entire set of tests.

[valepe]

@Poisson can you share your nevermore fans configuration? thx

[Poisson]

7 hours ago, valepe said:

@Poisson can you share your nevermore fans configuration? thx

nevermore.cfg

[ken226]

On 11/22/2022 at 7:36 PM, Poisson said:

 

 I should mount the bed fans somewhere near the back so they are also pushing from the back to the front, however I have a decontaminator bucket one one side of the rear and I haven't thought of a good way to set this up yet. 

Hate the revive an older, long dead thread but it kinda related to a CAD project I've been playing around with for a few days.

 

What about a bed fan/charcoal heater that mounts the fans in the front?  Kinda like a backwards Nevermore?

 

I like the concept of the nevermore, but having been trying to come up with something that draws air from the front, and moves it through a charcoal filter, under and across the bottom of the bed, then out each side of the bed.  It uses two small, 3010 centrifugal blower fans mounted at an angle in the front.  I tried to keep a cosmetic appearance something like the Voron Stealthburner theme.  

The toughest part is designing everything compact enough to fit in the small space available, yet still actually work. 

 

Here's where I am so far on this.  I'll be printing and testing over the next few days.

 

 

 

Edited December 17, 2023 by ken226

[ken226]

 

The holes in the top lid are angled, so that they direct the air out to the left and right.  The air should flow in from the front,  then flow across the bed to the left and right, passing through the space between the bed and the 2020 rails that the bed is mounted to.  As long as the OEM design spacers are installed, and the bed isn't mounted directly to the rails there should be a gap for the air to pass through.

 

Edited December 17, 2023 by ken226

[ken226]

The filter slot should accept the generic rolls of activated charcoal filter material available from Amazon.  Cut to size with scissors.

 

[ken226]

[ken226]

[CarMAN3]

On 12/18/2023 at 10:03 AM, ken226 said:

 

How did it work?  Do you have a STEP file available to test?

[ken226]

On 1/21/2024 at 1:53 PM, CarMAN3 said:

How did it work?  Do you have a STEP file available to test?

It works pretty well, but it was alot of work to get it working well.  There was hardly any space in that area to fit the fans, so there are alot of areas that didn't seal very well at all.  I covered those areas with some RTV,  and got it working.

 

To be honest,  It probably wasn't worth the effort required to get it working well.   

If you are interested in playing around with it, i can send you the .stp file.  Unfortunately it's bigger than the 4.88mp limit, so i can't upload it here.  Send a private message with your email and i can email it to you.

 

Edited January 23 by ken226

[Munchkin]

@Poisson Did you ever manage to find a way to mount the seperate fans somewhere at the back while still keeping the decontamination bucket.