Some issues with new MakerFarm Prusa 8 i3v

[TehStranger]

Hello all!

So, I am new to this whole 3d printing thing, I just got my printer all setup today and I am having a few issues.

I have a Prusa 8 i3v with 0.40MM 1.75mm Hexagon head

1: My prints aren't sticking to the glass I tried the hairspray method and it didn't help much.

2: The filament is barely extruding, and when it does it curls up.

3: The extruder is kind of popping off the V rail.

I'm not sure how to level the bed exactly, I just made the head EXTREMELY close to the bed.

I am currently trying to print with PLA and the temps I'm using is 250c for hot end and 80c for the bed. I tried with 220c for the hot end but it was even worse and if I go higher than 250c the curling issue remains.

I will post a video and some pics soon of the extruder to show how it just comes off the rail.


Any help would be greatly appreciated.

Thanks!

[JohnA136]

Something is definitely wrong there. You should not have to use temps that high for PLA? I use 50 or 60 for the HBP on my Prusa 13, my son uses 40. We use 3mm extruders on our Prusas but I have never had to go above 220 degrees. Are you sure your thermistor are set in all the way in your hot end? I might try and get a real temp reading with a laser thermometer? I print right on blue painters tape all day long? Wipe with alcohol if you want it to REALLY stick. Curling of the filament might mean you have dirt in the nozzle? Try cleaning that out.

[printbus]

I have the same extruder setup on my i3v. Comments and suggestions:

1. Are you feeling the heat bed getting hot? Or at least pretty warm? I've had no adhesion issues with PLA from three different sources sticking on the glass when running the bed at 70 degrees, hairspray or not.
2. I often see curling if I'm extruding only small amounts into free air, but no curling if the extruder is running at a normal speed. I think the melted filament just tends to stick more to one side of the tip. Note that I noticed in my build that two of the v-pulley bolts on the X carriage were long enough to rub against the large gear on the extruder. If not fixed, that would keep the gear from rotating properly and the extruder from pushing through the right amount of filament. Periodic catching on the bolts would lead to the x carriage being torqued, possibly leading to your popping off the rails?
3. Something's not right here. With the eccentric spacer adjusted properly, the X carriage and extruder shouldn't be able to pop off the rail.
4. A lot of people adjust the bed with only a piece of paper used as a thickness guide for the gap between the hot end and the glass.
5. 250 degrees seems pretty high. Are you sure the thermistor is making good mechanical contact with the aluminum body of the hot end? I used a tab of automotive muffler cement to keep mine in place.

My build thread might have other i3v suggestions you find interesting. I found numerous ways to tweak the i3v as I built mine.

EDIT: I see JohnA136 and I have some of the same ideas. I'd also look into how to calibrate the amount of filament being extruded. That process would reveal whether the extruder is going through the filament like it should.

[Roxy]

This may or may not help you. But it will give you a little bit of perspective. With PLA, I typically print at about 195. If you raise the nozzle 50 or 75 mm above the bed so you have some room, you may want to try this. Set the temperature to a point where you can manually extrude some material without using a lot of force. By manually, I mean turn all the stepper motors off (big button in the upper left of PronterFace) and gently turn the extruder gear. Then, raise the temperature 10 degrees and let things stabilize. Turn the gear again by hand. Perhaps repeat this process a couple more times at 210 and 220 degrees.

You will see and feel a couple of things. First, the filament almost starts to squirt out as the temperature gets too high for PLA. And you will feel the extruder gear requiring less force to turn as the temperature goes up. You may have a clogged up nozzle. I don't know, but most of the problems are pretty simple if you can get to root cause. It is figuring out what is wrong that is difficult.

You can print at the higher temperatures, but the filament doesn't hold its shape and the object you are making gets pretty poorly defined.

[TehStranger]

Thanks to everyone for replying. I've been busy so I haven't read anyone's posts yet but I will after this. I noticed the hot end is VERY loose and i noticed theres filament leaking from the top of the hexagon nozzle. I will post a video.

[JohnA136]

Roxy has a great point there, old man ole also suggests this to gauge a good extruder temp but I always forget to mention it. Give that a try and then go level your bed. That has to be done if you want reliable, consistent prints. I spend the time to get it right when I first build and seldom have to goof with it again. Good Luck and let us know how you make out.

[printbus]

Thanks to everyone for replying. I've been busy so I haven't read anyone's posts yet but I will after this. I noticed the hot end is VERY loose and i noticed theres filament leaking from the top of the hexagon nozzle. I will post a video.

My hex hot end tip was loose as well and needed to be tightened. More thoughts -

The hobbed bolt pushes the cold filament up against a bearing that must rotate freely. I had to work at the bearing mount quite a bit to get the bearing to rotate freely. That could be hanging things up.

It's easy for the hobbed bolt to dig into the filament. Once that has happened, you need to retract the filament out and re-feed the filament after cutting off the worn part. I can't say this is part of what is going on, but figured you should know.

Don't try to use the manual LCD control to drive the extruder. I haven't had good results with that. Either disable the steppers as Roxy said or use Pronterface.

[TehStranger]

I haven't had time to cut and convert the vid so sorry guys I might do it in the next hour. @printbus I tried tightening it but it's impossible because I think the melted filament clogged it up and it's impossible to move when it dries. @roxy I did that but it didn't help. I levelled the bed and the results are much better but still curls after a few seconds and the whole print gets stuck to the nozzle, dries up and moves around with it.

[Roxy]

I levelled the bed and the results are much better but still curls after a few seconds and the whole print gets stuck to the nozzle, dries up and moves around with it.

This may not help you. But I got a roll of cheap PLA. If I let it sit in the nozzle too long with the heat on, it clogs the nozzle and I get that curling you are talking about.

Here is what I noticed on the front end of dealing with the issues it was causing. If I manually retracted the filament by hand so I could change to another roll, the end of it would stretch. The very end of it would have a clear, crisp shell and not much plastic inside of it. But there was a clear crisp shell on the outside sort of pulled to a point. So of course, I turned the heat way up and tried to push the remains out the nozzle. No luck. That clear crisp layer just didn't want to melt and extrude. I ended up having to take the nozzle off and clean it up.

Since then, I can print fine with that cheap roll of PLA but if I let it sit in the nozzle too long with the heat on, I see that curling behavior start. If I don't let it get too bad, it will clear out. But it seems like there is a point of no return on that PLA roll.

It might be interesting to heat up your nozzle and pull the plastic out and see if you see something like what I ran into.

[TehStranger]

@roxy Yeah I got cheap PLA too and I saw that clear shell also. I took off the nozzle and theres was nothing inside of it but I cleaned it anyway and its still doing the same thing. I will try what you said though. Also, How do I tighten my Hot end? I tried turning it but it doesn't tighten and there isn't a nut i can hold with a wrench like in the build guide :S

Edit: I also mentioned the nozzle is leaking before, could that be the problem? if so how do I fix it? It's already tightened really good.