Extruder Struggling

So new issue… (most likely the result of operator error.) So after a successful print and then me messing around with the printer. I have some how messed something up… again. Now my extruder only is extruding a small amount of a plastic in comparison to how much the the hobbled bolt is and extruder gear drive is turning. It appears as if it struggling to force filament down thru the nozzle assembly. It is not clogged as some filament is coming out just not enough.

My guess is that I have managed to get some extra semi melted plastic up in the threaded assembly and so it is creating resistance.

My plan is to take nozzle apart this weekend. See how everything work and try and find the problem. I just hope I will be able to get it back together again and that I haven’t melted any PEEK or PTFE componets. I just ordered some other parts yesterday and don’t want to have to order more.

If anyone has any experience or advice, It would be greatly appreciated.

There are a couple potential issues that can cause that. The first is filliament shavings in the hobbed bolt chamber. if they work their way into the bearings, they can jam things up. THe filliament may also have a chunk missing out of it if you were trying to extrude and nothing came out. Undo the idler open the filliament chamber, and if it has a chung removed, pull it out and reinsert the filliament after cutting away the part with the chunk missing. You may also have idler tension set too high or too low. The proper tension is listed in the manual. There may also be a partial obstruction. if you loosened your hot end at all and re-attached it, it might not be properly alligned with the extruder body and can be causing extra friction. The NEMA motor itself is another potential source of trouble. make sure the small set screw in the small gear is tightened down and alligned with the flat part of the motor shaft. I ran into that once with my printer, the motor turned but it would only extrude a small amount of filliament.

I tried pulling out the filament and checking to see if it ground through the filament. I also cleaned out the hobbled bolt teeth. I can see that it is struggling with the filament but it is making slow progress. How tight do you keep your idler bolts? I know it the manual it say keep them about 20mm away from the extruder body.

I haven’t taken off or loosed the hotend (yet). So I am not sure how I would have misaligned in that way.

I will check to set screw but I can see the gears are moving at what appears to be the normal rate. :nerd:

What type of plastic are you using? What temperatures are you using?

It’s dangerous to go alone, take this:

http://devel.lulzbot.com/Budaschnozzle/v2.0/budaschnozzle_2.0.jpg

I wouldn’t recommend taking anything apart just yet, you’ll want to approach this in as minimally invasive of a method as possible. The above tips are a great starting point. I would look at the tension of the two screws on the extruder. You’ll want to have the distance between the two silver washers around 5mm apart.

Orias,
Oh come on, I am an engineer! We love taking things a part and poking around (with marginal probability of getting everything back together correctly). But in all seriousness I don’t want to do more than is required.

What two silver washers are you referring two? We are dealing with a “Budaschnozzle 1-1.3 Nozzles”


Rufu5,
I like the reference.

Makergeeks Black ABS PLastic http://makergeeks.com/abshiblco11s3mm.html. Recommended 235 for extruder and 115 for the bed. http://makergeeks.com/abs3dprfi.html

The two washers are on the two screws on the extruder body. Adjusting them controls the tension on the filament against the hobbed bolt that drives the filament. It’s generally the first thing you’ll want to look at when experiencing extrusion issues.

Note: Makergeeks ABS. I don’t know about their filament, but I can tell from their reels it isn’t the same as ours. Don’t heat your Buda above 240C. If the ABS requires it, you need to get some other ABS.

Orias,
Are these the two washer you are referring to(denoted by yellow arrows in image below)? I am confused per the manual I thought it was supposed to be 20 mm from the washer to in to the inside of the thumb screw.


Jebba,
When I recover a little more for the holiday, I will try your filament out. I asked one the Aleph Project guys if there was any sort of deal on filament when I bought the printer. All I got was a nope, so I tried to save a few bucks on a filament and shipping. Is there any particular colors that prints really well?

Those are the two silver washers. You’ll find that some filament types and colors like more tension, some like less. Black ABS, LulzBot Green and Red ABS are some of my favorites.

The ABS is all pretty similar, but some colors just seem to have a better finish than others. The LulzBot green looks pretty awesome. Good old black works well, etc. Probably the only one that is a bit different is the glow in the dark.

Learning to print with dark green on dark green Kapton tape is to be avoided if you can. I learned that the hard way heh.

Well now I did it… I messed up the nozzle. I tried to take off the nozzle without heating it up and I ended up stripping out the threads on the shaft. I think the nozzle is still salvageable.

I am very frustrated with myself because this now mean I won’t be able to print for another weekend!!!

Does anyone have any suggestions on how to get the PEEK insulator off with out ruining it?

Also I found the original problem I think. The nozzle was not fully seated on the threaded rod…

Success (or at least from the moment). Today I made the long drive out to Deezmakers in Pasadena CA. They were able to hook me up with some spare parts and gave me some good advice.

Lessons Learned

  1. MAKE SURE THE NOZZLE IS ALL THE WAY ON!!!
  2. Use some anti-seize when you take your nozzle off.
  3. Nozzles are not meant to be taken on and off frequently
  4. Listen to others advice (Like Orias - would have saved me several hours and about 60 bucks)
  5. Patience. I tried to rush a couple things and it ended up costing me time and money.

Well I am happy to be back up and printing…

Cool, glad you got it up & running. :slight_smile:

That happened to me too. They tell, in the instructions to use plumbers tape, but when the unit ships doesn’t have any on it, so you cannot replace top easily after a while without out the stripping happening. I have two nozzles now, one with a 0.50mm tip and one with a 0.25mm tip. Normally only use the 0.50mm unless I want really good quality and have lots of time.

We ship all Budaschnozzles with a treatment of high-temp anti-sieze compound on the nozzle threads. If you were to use the PTFE plumbing tape, you’ll find that it can make removing the nozzle really, really hard. The anti-sieze compound was found to work best, but the type we are using is not readily available in smaller quantities and so, if you’re not going to be removing the nozzle, plumber’s tape is a more readily available solution. If you are going to be switching nozzles often, use high-temp anti-sieze compound instead.

I just used some Permatex Anti-Seize Lubricant http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_counterman’s-choice-anti-seize-lubricant-permatex_7730002-p?searchTerm=permatex+anti-seize it seems to work okay so far.

So I apparently I didn’t seat the PEEK Insulator all the way and now its clogged and in the process the heat resistor broke. I was going to order some repalcement parts from Lulzbot but they are out of stock. Does anyone know if something like the 12V 40W Reprap Cartridge Heater http://www.robotdigg.com/product/19/12V-40W-Reprap-Cartridge-Heater would work with the Budaschnozzle? If so what changes would I have to make? Would the best way to secure it be with a set screw?

Also does anyone know where I could get the little wire crimper things?

What size is the set screw for the Budaschnozzle block?

Hey Guys,
I am still having issues. I don’t know if its the filament our what but I got the new heater installed ran the PID update. I had a couple successful prints then a third of the way thru printing a job a on Friday night. The extruder jams again.

I stopped the print pulled out the filament, cleaned out the hobbled bolt and put the filament back in.

After warming it back up I used the manual extrude on Repetier and probably a small amount of filament came out put not the normal amount. I went to run a print and there wasn’t enough pressure.

I also checked the filament and it was spinning freely.

Would pointing a fan at the heat sinks help? My only though is that as it heats up it starts to jam.

I am getting pretty frustrated and could really use some advice. Maybe this is why this printer was for sale on ebay… :cry:

With extruder issues, you want to start at the source spool and work your way down to check things.

  1. Can the filliament spool move freely, or is it caught on something?
  2. is the filliament feed tube allowing the filliament to move through freely with no restriction (spcifically are the zip ties holding the tube in place too tight?)
  3. Is the filliament binding where the idler filliament guide contacts the upper extruder body? (If so, sand some material away until it is able to move freely
  4. Is the hobbed bolt grinding chunks out of your filliament?
    A. If yes, you have either a temperature or force issue for feeding.
    B. If no, your small gear on your NEMA motor isn’t tightened at the set screw all the way or your main gear is installed on the hobbed bolt incorrectly.

If you are getting chunks ground out of your filliament, there are several possibilities. One is that your idler is either not tight enough, or too tight. Not tight enough will wear away filliment slowly and won’t move it much. Too tight will immidiatly rip chunks out of the filliament. A clogged filliament chamber can also do this. Remove any excess shavings, make sure the bearings are not impacted, and clean the hobs of the bolt out with a toothpick or other pointy object.

If all that looks correct and you still aren’t able to feed filliament through the hot end, I’d suspect that it is not actually getting up to temperature. That would be really rare, and usually you would just see a working or dead hotend, not one kind of working unless the temperature was set wrong. If you are extruding ABS at 230 degrees C, it should come out with almost no resistance at all. If you try and print too close to the bed for the first layer and don’t catch it in time, that backpressure can cause the filliament to stop and get chunks ground out of it… If the extruder itself has a malformed filliament channel that can cause binding and cause the grinding issue, Stick a piece of filliament in that section and see if it moves properly. if it sticks, grind the hole out bigger on the ABS plastic exruder body itself (not your hot end)

Another troubleshooting step, dismount the hot end entirely and run filliament through the extruder. if its moving and moving properly, the trouble may not be there.

If you can, take a bunch of pictures of your extruder, the hot end, the idler chamber, the gears, etc. and post them here. maybe we’ll get lucky and spot the issue?