I have so many fans now!

[krak]

I must be popular, or blowing a bunch of hot air. Well hopefully I will be blowing hot air. On my Rostock Max I am installing three fans. 1 25 X 25mm pointed at the Peek tube, 1 40 X 40mm assembled in edward's duct. http://forum.seemecnc.com/viewtopic.php ... 60#p18171), 3 an always on cooling fan pointed the RAMBo board.

I have a few questions about the fans.
Is the 25mm fan considered Fan 1? I found in the configuration.h file that it might be refereed to as Extruder 1 fan. If so, how do I set it to turn on? I appears to be set 255, which I take to mean full power on, but the fan never does any thing.

Fan 0 on the RAMBo board seems to be able to be controlled with the LCD and Repetier. I would assume that this out would be for the 40mm fan, correct?

Last night, I started a print with the fan blowing on the RAMBo board. But the bed would not come up to temperature. When I removed power to the fan. The bed read higher temperatures. The fan is 5 volt directly off the power supply. Could cooling the board affect readings for the temperature?

[edward]

The temperature "sensors" are thermistors, which are resistors that change their resistance (a lot more than normal resistors) due to temperature changes. Since they are placed on the heated components, blowing air on the RAMBo board should not affect the temperature reading.

Something else strange is going on there. Maybe some pics or your electrical setup?

I can't really comment on the correct fan pins/ports, as I use a RAMPS board...anyone else have suggestions?

[Cleveralias]

The 25mm fan is EXT0 cooler in configuration.h and by default is set to 255. It's mapped to HEAT_1 on the RAMBo, and the part cooling fan stays at FAN_0 as you said.

[lordbinky]

I believe that excessive air movement in base does a good job of actively cooling the bed. I had a high static pressure fan blowing on the rambo and my bed couldn't get above 70C when it was on.

[edward]

I didn't even think about this, but I remember experiencing the same thing when I first got going. An easy fix is to remove your heated bed and put some tape over that hole in the middle of the melamine support.

[krak]

The 25mm fan is EXT0 cooler in configuration.h and by default is set to 255. It's mapped to HEAT_1 on the RAMBo, and the part cooling fan stays at FAN_0 as you said.

Ok I had the 25mm wired into Fan_1 instead of Heat_1. Now it starts as expected. Is there a particular reason to use HEAT_1? To upgrade to a Dual, wouldn't this have to be changed?

I believe that excessive air movement in base does a good job of actively cooling the bed. I had a high static pressure fan blowing on the rambo and my bed couldn't get above 70C when it was on.

Yup, I have the fan on when the power supply is on. It moves a lot of air.

I didn't even think about this, but I remember experiencing the same thing when I first got going. An easy fix is to remove your heated bed and put some tape over that hole in the middle of the melamine support.

I see from the top side, under the heated bed that the hole is not covered, although I though I covered when I assembled the machine. The temperature in the had dropped that night, so I am going to try it again. If it does not work I'll cover the hole over. It's good to know the air does not affect the thermistors.

OK off to re-tune the PIDs. Thank you for all, for the quick help.

[edward]

t's good to know the air does not affect the thermistors.

Not sure what exactly you mean by this. *Any* air of any temperature blowing over a thermistor will affect its temperature. It will eventually converge to that temperature, all else constant.

My previous comment was stating that the air blowing out of that center hole onto the bottom of your Onxy, where the thermistor is located, will cool that section of the board and the thermistor will indicate the drop in temperature. My guess is that your build surface was plenty warm as the controller should have noticed the error between the commanded temp and the measured temp, but it was the direct air stream right on the sensor location was causing the problems.

[krak]

t's good to know the air does not affect the thermistors.

Not sure what exactly you mean by this. *Any* air of any temperature blowing over a thermistor will affect its temperature. It will eventually converge to that temperature, all else constant.

My previous comment was stating that the air blowing out of that center hole onto the bottom of your Onxy, where the thermistor is located, will cool that section of the board and the thermistor will indicate the drop in temperature. My guess is that your build surface was plenty warm as the controller should have noticed the error between the commanded temp and the measured temp, but it was the direct air stream right on the sensor location was causing the problems.

Sorry I should have specified air blowing on the RAMBo board does not affect the readings. As for the hole in the base, I did cover it. I reran the PID tuning for the Bed and Hot end. The first calibration print came out pretty good, but I might to adjust my retract settings as the single wall cube has a few holes in it on one side.

[MDMD]

What's the proper way to wire fans and a light ring to the Rambo? I currently have my fan hooked up to Fan 0.

I previously had the LED ring hooked up to Fan 0 and manually turned it on and off with the 'Fan' control in RepHost.

How do I maintain manual control of the LEDs now that I have a fan wired up?

[Cleveralias]

What's the proper way to wire fans and a light ring to the Rambo? I currently have my fan hooked up to Fan 0.

I previously had the LED ring hooked up to Fan 0 and manually turned it on and off with the 'Fan' control in RepHost.

How do I maintain manual control of the LEDs now that I have a fan wired up?

I use this: http://www.amazon.com/LEDwholesalers-Di ... pwm+dimmer

You can ditch the plastic case and the board is only ~3/4 x 1", so it's very easy to find it a home, and the shaft for the pot (but not the plastic dial) fits in the "light" hole on the melamine front panel.

[MDMD]

Very nice idea. Where do you have the wires from that running to on the Rambo? Fan 1?

[Cleveralias]

No need to involve the RAMBo - you can power the dimmer directly from the power supply. I've had the same one in use for some kitchen lighting for years, too, so it seems to be a good $4 investment!

[bubbasnow]

What's the proper way to wire fans and a light ring to the Rambo? I currently have my fan hooked up to Fan 0.

I previously had the LED ring hooked up to Fan 0 and manually turned it on and off with the 'Fan' control in RepHost.

How do I maintain manual control of the LEDs now that I have a fan wired up?

what is the part number for the led's you have installed? and how many?

[MDMD]

what is the part number for the led's you have installed? and how many?

I'm using tricklaser's led light ring.