Extruder/Hot End problem during first layer

[dajay23D]

First, is the skirt layer considered to be the first layer? I'm having a tough time getting the initial layer down correctly. I'm not sure if it's my hot end or my extruder, i'm still experimenting and searching. I can get the filament to extrude and come out of the nozzle fine BEFORE it actually prints. But after I hit that start button and wait for another 5-10 min to print temp, that's when the initial problem occurs. There seems to be lots of delay when the filament actually comes out of the nozzle(biggest concern). I've looked at the bowden tube and the extrude gears are moving and the filament is moving. But, nothing will come out for a few passes. Then the filament will finally come out. But, then it doesn't stick right away. It'll slide across the surface. I'd say it takes another pass for it to finally stick correctly and then it will start to print correctly. This problem occurs pretty consistent with EVERY print. This problem sound familiar to anyone? From watching other videos, I believe the filament should come out instantly when the nozzle plunges to the correct height.
I've tried to remedy the problem by creating skirt layers. But sometimes, depending on the size of the print, 4 skirt layers isn't enough. I've tried up to 6 layers so far. I've tried more layers with increased distance, but oddly, every time, the filament doesn't come out until the last layer of the skirt. It doesn't stick enough, so the defects gets pulled into or curls into the actual part.
I've also used Aquanet Extra Hold hairspray as well as the elmers glue stick to help with sticking the ABS to the bed. Although, it does help, but it seems I need to apply the hairspray or the glue LIBERALLY. It's still giving me the above problems. The bed is leveled, although, i can try to level it again having the nozzle closer to the bed or have more resistance to the paper scale.
I've let it go and continued print on some simple parts and it seems to be decent. My skirt layers are pretty accurate when it actually prints. Some of the calibration disk thickness' are off a bit, but they're even and consistent. I've printed half a block and the sides are pretty straight besides the "stitch" looking corners/layers.
I'm using MatterHacker's 1.75 purple ABS filament. Using MatterControl. My MatterControl settings are Gene's assembly manual recommended presets for ABS.

Thanks in advance.

[Tincho85]

But after I hit that start button and wait for another 5-10 min to print temp, that's when the initial problem occurs.

That's a long time. Hit start when both hotend and bed are at print temperatures, and before you start your print extrude 20mm of filament. Here take a look at the extruder, does it retracts before printing the skirt?

But, then it doesn't stick right away. It'll slide across the surface. I'd say it takes another pass for it to finally stick correctly and then it will start to print correctly. This problem occurs pretty consistent with EVERY print. This problem sound familiar to anyone? From watching other videos, I believe the filament should come out instantly when the nozzle plunges to the correct height.

Yup! been there. Bad adhesion.
Try with ABS juice (abs+acetone). UHU sticks works excelent for me. Kapton tape with bed at 100ºc sticks really well too.
Also, print the first layer very slow, like 15mm/s and see what happens.


What's you hotend and bed temperatures?

[dajay23D]

Thanks for your replies.

That's a long time. Hit start when both hotend and bed are at print temperatures, and before you start your print extrude 20mm of filament. Here take a look at the extruder, does it retracts before printing the skirt?

I didn't notice it, but I look more carefully tonight. I know that it works properly after this initial issue. I'll prime the hell out of it and get everything to temp before I press that "start" button. Maybe that's my issue.

Yup! been there. Bad adhesion.
Try with ABS juice (abs+acetone). UHU sticks works excelent for me. Kapton tape with bed at 100ºc sticks really well too.
Also, print the first layer very slow, like 15mm/s and see what happens.

Yea, I've read all that, but I was confident, I'd get it to stick, I didn't think it'd be this annoying.. I'll try the specific UHU stick to see if there's any difference than the Elmers Disappearing Purple. I'll try a few times and if not, I'll try the PEI.

What's you hotend and bed temperatures?

I'm using Gene's ABS presets in the assy manual, so 230C hot end and 80C bed temp. I've tried to increase the bed to 90, but didn't do anything.


Thanks again! Off topic a bit. BTW, I looked at your build. Pretty cool. Eve though, i haven't solved these novice problems, I'm already thinking about building another..lol. For the extrusions, I was thinking about using these instead; http://www.mscdirect.com/product/detail ... 0=57283764

I feel like the extrusions are flimsy. Also, the filament holder is a joke. Everytime my spool spins one revolution, it shakes the whole machine. During a print, too. I'm going to build a holder that's not attached to the machine.

[geneb]

You could just print one of these: http://repables.com/r/204/. I've got them on my machines and it works perfectly.

g.

[dajay23D]

You could just print one of these: http://repables.com/r/204/. I've got them on my machines and it works perfectly.

g.

thanks!