Damn it! Probably only valid links in my session. Does these work better? http://www.digikey.com/product-detail/en/delta-electronics/AFC0612DB-F00/603-1169-ND/1860243 http://www.digikey.com/product-detail/en/delta-electronics/AFB0512HB-TP41/603-1488-ND/2560612 With temp control the noise will hopefully be lower anyhow. Will the bigger fan be able to get more air through the holes? Except to make bigger holes.
Those look pretty good! Is shipping to Norway reasonable from Digikey? It's definately worth the try with temp control. Be careful though because the RUMBA definately needs cooling. My stepper drivers get so hot I can't touch the main chip. Even though I've tuned the voltages.
Last time I ordered something it was reasonable. i have still to push the button. You have good points about cooling the RUMBA. If it's that hot maybe it should have better cooling fins on the hot components. If there are none maybe a small footprint fin and some thermal adhesive would do. Think I'll see if I can dig up anything about this as I do not have one yet. Suggestions? If I were to buy a bigger fan I would have to make a bigger hole for air in the electronics cover right?
I've looked for a heatsink for these drivers myself but I struggle. They are really tiny. Also, a lot of people say you shouldn't have to do this because the chip is designed to loose heat through the bottom of the PCB. However I'm confident that it will benefit from a small heatsink. Perhaps cut up a bigger heatsink for example a Raspberry Pi one? Yes if you go for a bigger fan you need to cut a hole in the cover. I've planned to do this but I haven't had time. Will post photos when I do this.
I just ordered the fans I linked and the dual thermostat you linked. Plus a adjustable step-down with display because I'm lazy Shipping from digikey is about $12-14. I read somewhere on the forum that the drivers should come with heat sinks? And what you described about heat dissipation through bottom. I'll just see and if its a problem I will figure something out. Maybe placing the temp probe between the drivers
@JvdP I got my steppers cooled with these self-adhensive heatsinks from ebay. And since the get really hot when the printer is running, they are doing what they are designed for. I don't think the stepper chips are designed to loose heat at the PCB side of the chip, when I'm home I will try to measure the temperature of the heatsink when running.
Good idea. But I just measured the chips on the stepper drivers. They are 5mm x 5mm and the 8.8mm heat sink will get awfully close to some caps and resistors. Update: Finding any smaller heatsinks is difficult. They all are 8.8mm. I would be scared to mount them but they probably just clear the other SMD components.
@Stian Indal Haugseth : You indeed have to be very careful when placing the heatsinks. I will make some close-ups when I'm back home. To be continued....
The ones I have on my current printer are 6x8mm, I got them from here: http://www.hobbytronics.co.uk/dip8-heatsink Alternatively could you cut them down slightly with a Dremel or similar?
You'll find small ones here: https://www.multec.de/Kuehlkoerper-Pololu-ICK-SMD-A-5SA-64mm Edit: was wrong link
I placed a metal rulers short end on top to see if they cleared. It looks like a very small space between the closest components so I think it could should work. But the margins are small and just one bad solder blob an a component you could have a short. Thanks for the link! I found this one 6.3mm x 5mm and should fit perfectly. http://www.reichelt.de/Heat-Sinks-I...ION=3&GROUPID=3381&ARTICLE=113623&OFFSET=500& Update: And one of these: http://www.reichelt.de/Heat-Transfe...ION=3&GROUPID=3384&ARTICLE=112269&OFFSET=500&
A thought came to me. I have not yet mounted the RUMBA in the enclosure. I do not know how much space there is and if they will be to high?
I mounted the controller you linked @JvdP. Found a adjustable regulator with display The fans from Digikey have enough air throughput and can get pretty noisy when at full speed. I'll just have to dial in the fan regulator when it gets hotter in summer. I also got me connector housings and crimps as the fans are without connectors. I need to get a clear acrylic service hatch in the Bigbox
Made a mount for one temp probe on top of jtag connector so it's besides x/y steppers. Don't know if this is a good location. I have plastic over the probe so it will be shielded from the fan. A little stand for the second probe in front of exhaust fan. Finshed routing the wires.
I have been listening at the noises and my conclusions is that I can reduce it to a good enough level by using more silent fans. The hot end fans are bad (I admit I connected them to the supply directly because my BB is not ready yet), so they will be replaced by silent ones, the one on the board is rather ok, but I will still use a stronger more silent 80x80x10. The bad one is the exhaust and not easy to find a silent one with that form factor at 24v. Worst case I go for a 12v with dc/dc. I will make nylon spacers to reduce vibrations and use fan connector and replace the board cover with one in nylon as well (for vibration absorption).
I went for a quick and dirty solution too. It began to sound like the exhaust fan was massively over-specified (just because you have a 24v fan and 24v doesn't mean your run it 100%) so I decided to tug its wires out through the back vent with a view to doing something. Two tugs and one broke so there was no alternative to loosen the base. Reached in, took out the fan, soldered a new wire to the broken stub and ran that, together with the "other half" (from the power supply) back towards the Rumba. Put fan and base back and began to experiment with resistors. Putting in 100ohm resistor already quietened it a lot. In the end settled for 300ohms. Instead of putting in a single 330ohm resistor (standard value) put in 3* 100 as below. So have the option of reducing the resistance by moving the crimp-jumper. Also printed a duct for the stepper fan that effectively doubles the air flow over the things that get hot. With a view to doing something there as well. Every kid who's played with a fan on summer holiday knows you can't sleep with it on full, but take it down a bit and it sounds very different.
I'm satisfied by the above 300ohms for the exhaust fan and so have now replaced it by a single 330ohm resistor. I'd expect that Bigbox 1.2 will probably be so equipped! ;-) Though seriously, I wonder if there is any real need for an exhaust fan at all: there are already lots of nut traps, plus the exhaust fan aperture... perhaps a few more holes around the back and air exit could be entirely passive? A couple of days ago I put a 100ohm resistor on the Extruder Fan. That's just enough to take the harshness out of the sound whilst still leaving lots of cooling power. Am too lazy / occupied to experiment with higher values (for now) but happy to grab this low hanging fruit. Now when watching layers go down with even less fan noise I start to hear new sounds, like she's talking to me..... ;-)
I ended up putting a resistor inline the exhaust fan as well. I used a higher resistor ~600ohm or so. I also put both the Rumba and exhaust fan on a relay board controlled by my Raspberry Pi so I can enable both fans only when the BigBox is printing and otherwise no fans when just sitting idle. At idle and no stepper drivers running I don't see the need for active cooling. Anyone see any issues with this?