I started using one large fan to cover the whole build area. I find this to be better than individual fans for the print and heatsink. and way easier to install and maintain. Is there something Im missing as to why this wasnt the way printers were designed?
I think that a fan that focuses the air stream directly under the nozzle tip is needed for fine details.
Without that fan effect the fine details tend to come out as a blobbly mess because the new plastic gets laid on top of plastic that is too hot and it tends to result in a big blob.
I found that when I tried to print Warhammer 40,000 parts I couldn’t get the details to print without the fan directed right below the tip.
Did you have a different experience with printing fine details?
You need to be able to turn off print cooling for most materials other than PLA. Air flow on the heat block is likely to make it difficult to reach and maintain higher temperatures.
@Bruce_Moore will it harm other material?
@Paul_Gross so far it seems to do a better job.
@Dovid_Teitelbaum For ABS, in particular, you want the layers to stay hot for good bonding. Print cooling may cause layers to delaminate.
@Dovid_Teitelbaum I just tried what you described: I used a small desktop fan (16W mains-powered) blowing across my bed and the results were surprisingly good!
I printed a fiddly part in PETG that normally requires a tip fan - without a fan the part prints all blobby and the bridging sags very badly, but just the desktop fan alone made it look pretty good.
The bridging on PETG is not quite as good as the fan at the tip of the extruder, but nonetheless its a very good result when compared to no fan at all!!!
The extruder tip fan is slight improvement for bridging PETG, but not really a huge problem. I guess I could just use a bigger desktop fan very easily too.
So - Thanks very much for your post - I always prefer to keep things simple if possible, and a desktop fan is a very simple solution indeed!
I will switch to PLA filament and try that with the desktop fan next…
Breezes on ABS are bad. Breezes on PLA are good. I do not really know about the other materials, but they will probably be like ABS or PLA.
Breezes on cooling fins of hotends are good. Breezes on nozzles and heat blocks of hot ends are bad.
Breezes that cause heated beds to have inconsistent temperatures are quite potentially bad since if you need a heated bed to be hot, having some of it cold may cause prints to curl.
At this point I’m not doing abs on this printer because it’s in a public area and the smell is bothersome. It would be nice to know where the best placement for fan would be.
@Dovid_Teitelbaum I put my 16W desktop fan higher than the extruder, blowing downwards past the extruder motor towards the middle of the bed.
Where did you put your fan?
How powerful is your fan?
Right now it’s a box fan blowing sideways but I assume you have it correct
@Dovid_Teitelbaum you do PLA or something else?
Make sure you do not cool your nozzle or heat block.
@NathanielStenzel pla right now. My block is insulated
@Dovid_Teitelbaum the insulated nozzle explains why you do not have intermittant extrusion issues which would result from hotend temperature control issues.