Welcome to the SeeMeCNC Community

Hi,
I am rather new here, so some questions will be of the beginner type...
I bought my V2 second hand, so pre-built The seller told me to always switch on the hotend fan before starting a print. It needs a GCode commend to be switch on and I made a macro for that in Mattercontrol, but I wonder why that is... Why doesn the firmware turn that thing on before starting a print? Probably I can change some settings somewhere that enables this "feature"?
Thanks! Con

Its probably how its wired in and how the firmware is set up. look up how it is done on the factory setup and you could probably wire it up the same. The firmware would have to be set up appropriately. If it was me, I'd wire it up properly, start with stock firmware and make the adjustments needed for the E3D - higher temps, different thermistor.

The builder must have wired the hot end fan to the layer fan terminals. Rewire it per the instructions and you'll get the functionality you seek.

Thanks, I will download the assembly guide and look into it.
Looks like I will be doing some rewiring all togther, because it looks quite ugly at the moment.

If it is connected to the proper connector, and you have the stock firmware then it should be on as long as the hotend is heating up and when it is above 40 degs.

There was some talk about this that e3d was recommending that it should always be on. I do not have an e3d so did not pay much attention to it.

Thanks guys,

Today I dismounted the RAMBo board and checked the wiring. The hotend fan was connected to the "fan" header while I found in the manual that it should be connected to the "heat1" header. So I corrected that and all is fine now. The fan goes on and off automatically (shuts down below 50, not 40 degrees BTW).

But that leaves me with another question:
I have a layer fan, as most of you do, but it is broken. I will get a new one, but does that need to be connected to the "fan" header? If so, the wiring for that is absent. The guy who built the machine also forgot the hotend fan wires and left them loose on the outside of the machine. I was able to pull them through the X tower using a thin iron thread. But I am pretty sure there is not enough space for another set of wires. Unfortunately I can't find anything on the layer fan in the built manual, and that's strange because the user manual starts with printing a layer fan shroud...?

You are correct. Itis wired there.

Look at the seemecnc site. There you can see the fan type. You ahould be a little bit familiar with the wiring by now, so you can print the fan holder and attach a new fan from seeme or you can shop around for an equivalent one or download an stl from thingiverse and attach another type of fan.

teoman wrote:You are correct. Itis wired there.

Uhm not quite... I checked the manual again, and of course I was mistaken. The layer fan is mentioned in the manual after all, I was just overlooking it. That's great because the wiring is okay then. I found an alternative to the layer-fan-shroud, that uses a regular 30mm fan instead of the blower that is hard to come by locally.

http://www.thingiverse.com/thing:1140703

Will be going to try that, but it probably will not fit together with the LED ring I am planning to mount.Weĺl see.

To reply to myself:
It seems to be difficult. The layer fans I've seen so far are all hanging too low next to the nozzle. And indeed it does not play nice together with the LED ring mount. You can't lower the nozzle a bit because the hotend fan blocks that... Any good solutions for the E3D? Do I really need to move the hotend to a position below the effector?

Here's some fan mounts that came out of the aluminum E3D mount thread, from Bot: http://repables.com/r/553/

Hopefully one is low enough profile for you. As far as the LED ring, well, I might use one of the customizable E3D fan shroud designs, I remember finding one on Thingiverse, and create a sloped bracket to give you a few more millimeters of clearance.

If you plan on mainly printing ABS and similar, there is less need for a layer fan.