Simple cooling fan (revision 1)

Photos of my test version of a cooling fan. Here the fans is mounted using double faced tape just to see if the concept is right,

In place:

Bottom view:

Fan inlet:

Cooling air out:

Next revision: Mounting holes for fan, Air out a little lower and closer to the filament.

/Niels

Something is rotten with the Vertex Hot-end

Well. The Vertex hot-end sucks.

I have made a few experiments with the Vertex hot-end.

The first experiment was to modify the mounting of the temperature sensing ntc. My thought was that the thermal resistance between the alu-block and the ntc was too high, So I removed the insulating hose around the ntc. Drilled a 2.8mm hole in the aluminium block so the ntc could be mounted inside the block. Just like it is done on other hot-ends.

Then tried to load ABS. 10 minutes observation of temperature. Marlin never found the temperature stable enough to let the filament load begin.

Next experiment was to replace the Vertex ntc with a 100k ntc from an e3d-v6 hot-end.
Result: same as above. No filament loaded.

I don't know much about hot-end design but something is wrong with the Vertex hot-end.

What to do next? Well I have an extra e3d-v6 hot-end so a quick-n-dirty test prepared. Connectors for heat, ntc and blower was soldered and connected to the controllerboard. The ptfe tube moved from the Vertex hot-end to the e3d-v6 hot-end. Photo below showing pla flowing from the hot-end hanging in the ptfe tube.

Nano powered up and ABS-filament load requested. Temperature raised to 240deg very fast and within a few minutes molten filament was streaming out from the hot-end.

So I have a small job replacing the Vertex hot-end with the e3d-v6 and then recalibrate the Nano.

Below is from the first testprint  with the e3d-v6 hot-end. Filament is white pla that I usually print at 200deg on my Prusa, (first layer of 210deg). Time from power-up (26deg ambient temperature) to print started about 2½minute.

Now happy printing :-)
/Niels

PS All tests is done with the Marlin version from Vertex.  

Sucessfull fan test.

Today I tried to connect a small 25mm fan to the LED-outputs and it works.

The fan runs from led value of 100 downto about led alue 25.

Next to design a fan duct to be mounted on the hot-end.  Either the original or an e3d-v6.

happy printing
/Niels

Frustration. Waiting and waiting and waiting ... PETG

Tried to load PETG filament.

Limited or no sucess. PETG prints at same or a little lower than ABS so I loaded 1.5cm in the extruder and pressed "Load ABS". The temperature cycled between 225deg and 239deg never above when I was watching the printer. I left the workshop with the printer on and when I came back about 10 minutes later it suddenly began loading the filament, strange!

I then loaded my testprint from the SD-card and requested a print. I aborted the job after 10 minutes waiting :-(

PID tuning with a target temperature of 240 deg didn't help at all.

Next step. Replace the factory hotend with an e3d-v6 and try again.

Happy printing
Niels


PS: I don't understand the factory PID-numbers. The numbers I get from PIDtuning is way off the factory settings.

PPS: Maybe a Crazy Idea: The missing cooling fan. I have no need for adjustable LED light. Instead the output can be used to control a variable speed cooling fan. I'll dig into that during the next few days.

A few tips.

A few tips when assembling the printer.
 
Glue those small stand-offs to the cabinet. This will save you a lot of time later on.

Mark all the connectors. Again a time-saver :-)

In the assembly instructions you are instructed to move the x- and y-axes by hand. That's because the rods arent that smooth from the beginning.

My tip is to rotate the rods in a drill and then use a piece of steel-wool and a small amount of oil to smooth the rods.

After that I had no bindings on either the x- or y-axis.

Happy printing
Niels