a few niggles that wind me up

[lee 2]

ok just a few questions that get on my nerves with the printer and hope maybe I've done something wrong...

1) On the 2nd > * layers i get the following (see pic 1)

can you see how its not flat, some parts are though, and some look like this...

 

 

2) Does anyone else's print head seem to overflow? (see pic 2)

I've tightened it up as much as it will go but still pours out... i have to sit here "watching every print" like now (printing = http://www.thingiverse.com/thing:49954) and i have to keep wiping the block every few mins with a damn off cut of a sponge. surely thats not normal... I'm sure you lot go off to bed.

I cannot sit longer than a 2-3 hour print; where I know some prints can be over a day! (the Doc Who tardis jewellery box)

 

[nick-foley 5]

Something is assembled wrong, and your prints look bad because you're underextruding. Make sure you're doing the tightening of the hotend while the entire assembly is hot - I crank it up to 250ish when getting everything snug. Make thermal expansion your friend.

 

[gr5 2,024]

Nick is right on both counts.

Stopping this leak by tightening is not easy. I think you have to do a complete disassembly. Either that or raise the 4 screws, remove heater and temp probe and rotate the whole aluminum block. But it needs to be well over 180C when you do this.

Or you can take it apart and put teflon tape in all the threads - the problem isn't with the nozzle threads - it's higher up in the threaded brass tube.

Another way to stop this leak is by printing with some abs for a few minutes and then switching back to pla. The ABS will leak out of the cracks, and then cook and boil and blacken and gum up and seal all those leaks. UM used to ship a meter of ABS with every machine and the purpose was to seal up the leaks.

But be careful if you tighten with a wrench - brass is not very strong.

Your other problem I agree is underextrusion. Try printing a little slower maybe. Or maybe tighten up the spring on your feeder. Or raise the temperature a little bit - maybe to 240C?

 

[jonnybischof 60]

It shouldn't be necessary to seal things up. My UM1 (bought in August) never leaked at all. Not even a little.

I'd also suggest you take it apart and put it back together. Take lots of pictures of the assembly so we can tell if you did anything wrong!

Don't just keep printing like that - you won't get usable results.

 

[IRobertI 516]

With that much leaking I wouldn't be surprised if that's causing half of that under extrusion. After you have sorted out the leakage measure your filament carefully and check that it matches what is set in cura as well.

You also look to be having a problem with bed leveling. To me it looks like your bed is too high on the first layer. It's especially obvious in the hole which hasn't adhered to the bed at all. You say that some parts are flat while others are not, this too could be due to a wobbly bed. This could also be due to under extrusion of course.

 

[lee 2]

when you say teflon tape, isn't that plumbers tape? that non sticky thin white tape they put on pipe joints.... will that be able to cope with the heat? last thing i want to do is stick things in my print head and clog it up?

if it will cope with the heat i will goto DIY store tomoz and pick some up - but want confirmation first

 

[illuminarti 18]

Yeah, the kit used to come with some of that. I've also used what is sold in the US as 'Oatey Great White Pipe Joint Compound' - similar stuff in paste form, that comes in a tube. But tbh, just carefully tightening things should be sufficient.

You generally want to leave the nozzle not quite totally screwed into the block, then screw the brass pipe all the way until it touches the nozzle thread, and then tighten the nozzle thread back against the pipe. As others have noted,doing it when hot will help - indeed it's probably the only way to do it since you've gotten molten plastic in the threads.

 

[lee 2]

ok, so an update....

I dismantled the head, cleaned, tightened everything up adjusted some cables that were sticking out... now now look...

no leaking after 2 hours of printing.... (it does look a little dirty, but its EXACTLY the same as before i started printing #overTheMoon)

 

The quality has ROCKETED from something i though "i waisted my money" to this is exactly what I wished for...

 

And I'm even doing my first time lapse of this print - ill post a youtube vid

 

These forums are a god send, and the people who take time to help others out who do not need to but still use their own valuable time to rectify issues that us n00bs have are a credit to the internet...

 

THANK YOU ALL

 

 

 

[IRobertI 516]

Well it's certainly not assembled correctly but hey, if it works it works. Glad you got it fixed

 

[lee 2]

whats wrong with it =)

you on about the locking nuts and nylon washers

 

[IRobertI 516]

Take a look here and you'll see what I mean

http://wiki.ultimaker.com/Ultimaker_rev.4_assembly:_Extrusion_head#Lets_start.21

 

[lee 2]

thats how i did it originally but the PLA kept leaking from the top of the rectangular heating block (what ever the name of it is)

but by advice i lowered the nozzle and works a dream.

I was printing the odd thing once a day, now its working great I'm trying to print anything i can get my hands on haha wish i had a second printer - so ultimaker if your listening in, and need a test buddy ;-p i don't mind helping ;-) actually,. the most fun i had was to build this, id build these all day long if give the chance lol

 

[illuminarti 18]

Well, lower the nozzle yeah - but I was meaning by like half a turn or something... just enough to allow you to tighten the nozzle back onto the brass tube at the end.

Having it like this you've ended up with something closer to the original V1 nozzle that was notorious for getting blocked. If it keeps working for you, great. But set up like this, you're probably reducing heat flow into the tip of the nozzle, and also promoting heat flow up the tube into the PEEK part. As a result, you might get blockages due to filament softening in the area around the bowden/PEEK joint.

There's supposed to be a gap of exposed tube between PEEK and heater block, to help cool the top of the tube. Some people even add heatsinks and/or fans to cool that part.

 

[lee 2]

oh ok, does anyone have some sort of photo for me to look at how it 'should' be?

 

[gr5 2,024]

Just do it half way between how it was and how it is.

 

[illuminarti 18]

That photo Robert linked to shows it exactly. The PEEK screws down until it sits on the metal flange at the top of the tube.

Screw the nozzle in first - not all the way flat to the block; give yourself a turn or so of space so you can tighten the nozzle later if needed to take up slack. Then screw the brass tube up against it from the other side. Once you have it all assembled, tighten the nozzle again, to make sure its still tight against the brass tube. (Otherwise the joint between the two may have loosened as you were installing it, and that what can cause leaking).