[Bowden tube pop unplugged the temperature regulator]

Everything is still working fine after a couple days of constant printing.

I have a few questions I'll post in a new thread, so this thread can die out.

[Bowden tube pop unplugged the temperature regulator]

Sorry for the delay replying. I realigned the long belt pulleys per calibration wiki. Then, I loosened and re-tightened the short belt pulleys. Then I tightened the pulleys on the motors. Although none seemed loose, obviously one of them was. I'm guessing the X motor or short belt pulley was the culprit. It's printing away as I type this and I'm actually getting some parts made now.

The ONLY issue I have now is screws/nuts vibrating loose, but I picked up a bunch of nylock nuts and I'm going to replace all the normal nuts with these.

As much as I wanted to use white filament, I'm going nowhere near that stuff again. It just doesn't melt well enough to be extruded without plugging. If it wasn't for lack of a melting odor, I'd swear it was ABS since it is still thick and heavy at 230C. This gray stuff is awesome. Melts like butter at 220C.

EDIT: I thought I'd add a picture of a parts assembly I printed today.

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Fixed the vertical alignment issue. It just finished a 2.5 hr print without a problem. The object curled up a bit at the ends, but otherwise looked decent. Now, I just need to get used to adjusting for plastic shrinkage, and I'll be rocking!

Thanks everyone for all of your help!

I'll let you know how my next few prints go.

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Check that all of the pulleys are screwed on tight, including the ones on the small belts and the ones on the stepper motors. I once had exactly the same problems (funnily enough, while printing out the same belt tensioner) because of a loose pulley, but I didn't notice it until it got so loose that movement in the Y direction stopped completely.

Thanks! I'll take a look at those, too.

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Found small belt tensioner on Thingiverse.

http://www.thingiverse.com/thing:10082

Printed it four times and put them on the belts. It had no effect on the angled printing. Next, I tried loosening the screws on the motors and moving them to stretch the drive belts harder. That didn't help either.

Hey Daid, you mentioned current to the motors. Where would I be able to find out how to boost that slightly?

EDIT: I just went through calibration again. Loosened all the pulleys, measured spacing of blocks, got them perfectly even and re-tightened the pulleys. I'll test a print in the morning. I don't trust it running without me sitting here anymore.

Merry Christmas to all, even the grouchy ones.

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Actually, one of the things here is "Ultimaker white", our white PLA needs a higher temperature to print properly. But I do not know if it's labeled like that.

As for the slanted printing, it's always something mechanical. Anything from a lose pulley to bad motor current settings.

Thanks Daid. I didn't see any special temperature label on the spool, but that might be a good idea. The gray filament is coming out smooth at 220C while the white was coming out like putty even at 230C. Switching to the gray made a big difference.

I'm looking for a very small belt tensioner on thingiverse atm. A small object seems to print straight enough to be usable.

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I cleaned everything AGAIN. I ignored the instructions and set my print bed at double the thickness of the card which came in the box. (folded in half) I also switched out the white filament with grey. Guess what?

I just completed my first print ever.

 

Great to hear... It would have had been helpful to let us know that you were deeply embedding the first layer into the blue tape, and hence creating a crazy over pressure in the head that leads to stripping. But i guess you figured it out yourself. I assume you never saw the tutorials about first layer sticking and adjustments, and the fact that you can turn the z coupling to lower/raise the table for the first layer... I hope that is not part of your "ignored the instructions"

I repeat - I followed the instructions FIRST.[/b] They were wrong. So, I subsequently ignored those instructions and set bigger spacing by folding the card to double the space between the nozzle and the bed.

In a nutshell, I fixed the plugging issue by switching filament and doubling the space between the bed and the nozzle. It was never digging into the bed, and it definitely laid down filament, but the first layer looked thin to me. I increased the space because I HAVE seen the tutorial videos and it seemed that the first layer just wasn't as thick as it should be from the videos.

The output looks good now. It's just not vertically straight. I said earlier it was slanted in the Y direction only, I actually meant the X direction. The Y direction is perfectly straight. So, I probably have a loose belt on the X direction. I'm going to try to print out a simple belt tensioner for it.

Also, as an FYI, the difference between the gray and white filaments is HUGE. The gray is coming out very smooth and liquid at 220C. The white was always closer to the consistency of putty, even at 230C. I'd say the white filament was more than half the problem. I'm pretty happy with how this gray stuff is flowing.

[Bowden tube pop unplugged the temperature regulator]

I cleaned everything AGAIN. I ignored the instructions and set my print bed at double the thickness of the card which came in the box. (folded in half) I also switched out the white filament with grey.

Guess what?

I just completed my first print ever.

The item I printed, was:

http://www.thingiverse.com/thing:32044

I used normal quick print settings. My results:

As you can see, it printed, but at an angle. The vertical walls are very smooth. They're just not vertical. At first I thought "belt slippage" but it's so precise it seems unlikely. It's also only offset in the Y direction. I'm guessing something in my settings is wrong. Before I printed anything, I had restored everything to factory defaults using the Ulticontroller. Then, I ran through the Cura first run wizard to update the firmware. Then, I loaded, prepared, and printed it using Cura.

(EDIT: I just tried another object to print and it's doing the same thing.)

Any suggestions?

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There seems to be a lot of confusion. Hopefully these pics will clear up whether I assembled correctly. I've never put the brass upside down, btw. It's pretty obvious which end goes into the Peek. Here are the pics:

Hope this helps.

Btw, the PLA was on a spool, clearly labeled Ultimaker PLA.

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Hi,

one of the first photos you posted of the top of the printhead showed you trying to hold the bowden tube on the top of the printhead with a screw that you had moded yourself. what happened to the tube retainer that fits in the hole that the bowden passes through, it appears to be missing? you mention the horseshoe in the previous post so you must have fitted it, or did you give up and throw it away? If it didnt hold, then either the tube retainer is faulty of the OD of the bowden is too small to enable it to be gripped. I really feel for you but all I can say is that the system works, I've not had a single plug, leak or any other issue for that matter other than getting a feel for the parameter setting in Cura

Paul

Hi Paul, thanks for replying.

That screw was a last ditch effort to stop the bowden popping. Since then, I've ordered and replaced all of those pieces. The top piece, the bowden, the retainer, the blue horseshoe, and everything else is brand new now. It's all assembled according to the instructions. The bowden stays in place now without moving. Now, my problem is plugging on every print attempt.

Happy Holidays!

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A couple of things for you to check:

Heat up the hotend, and remove the nozzle

Remove the 4 screws holding the alu plate

Lower the alu plate, and remove any PLA in the upper part of the PEEK

Take a paper qtip, remove most of the cotton, and shove it through the still hot brass tube, to remove any PLA

Inspect the upper part of the PEEK for any PLA leftovers

Sanity check: the long end of the thread of the small brass tube with the flange goes into the PEEK, the short end into the alu heater block. You can the the end of the brass in the upper part of the PEEK, extending into the well about 0.5mm.

Clean the small teflon part

Clean the nozzle as best as you can (heat gun, oven set to 200c/400f, but dont let the nozzle go over 250c) with tweezers and qtips, try not to damage the nozzle

Tighten the nozzle against he alu again

Carefully tighten the PEEK brass tube against the alu block, until you feel the 2 brass tubes mate in the center of the heater bock. Dont over tighten. If the 2 brass tubes have a gap, it will cause a plug of sorts.

Remove the nozzle again, try not to change the depth of the upper brass tube into the alu.

Turn off the heater and let it cool (and hopefully you dont have burns on your finger tips from the previous steps)

Push the grey bowden retainer ring down a bit, and pull the bowden back up. This should be relatively easy, without damaging the teeth in the retainer or the bowden. If not, wiggle it untl it is easy. Dont force it.

Put the alu plate back ito place, and pay attention to the small teflon part going into he top of the PEEK

Tighten all 4 screws

The teflon part needs to mate with the brass nozzle, and make a tight seal (see sanity check earlier), in the upper part of the PEEK. Any gap between the teflon and the brass tube will make a plug

Push the bowden back down into the teflon part. Dont force it too much, you dont have to make a perfect seal. Put the blue horse shoe retainer clip back in

Unhinge.open your extruder feeder berthos thingi

Insert some filament into the bowden

Push it all the way through, and feel with your fingers if there are any obstructions.

If the filament comes out through the alu heater block without any issue, you are good. If not, figure out what the obstruction is ( make sure you clip off any thick end off the filemant)

Pull the filament back 10 cm out of the hotzone

Reheat the hotend

Put the nozzle back in, be carefull tightening it (remember the gap earlier)

Push the filament back into the hotend

You should be able too see plastic coming out of the nozzle, with reasonable force, about 10-15 newton... If not, bring up the heat by 5-10C (see davids comment earlier)

Close the hinge of the feeder mechanism (the spring should have a couple of mm left to compress)

Turn the extruder wheel with your fingers. You should see plastic coming out the nozzle while turning the wheel easily. If you feel a springy resistance, a clog has developed, and go back in this list to pinpoint the error

Check your z level, and check if the zero point is properly set. I assume this is explained in the wiki

Make sure you dont burn more holes into the acrylic.

Start up cura, and print something simple... Adjust the printing temp in 5C steps on te ulticontroller, until youi get a nice extrusion and print... Too cold and you get a matte print, too hot and it gets really runny and blobby. Make sure you cool the PLA print, and not your hotend. 210 is a good middle ground

Make sure you have a firm understanding how to wire the hotend, both electrically and mechanically, to avoid ay future hot end distructions

Start cura, and do some printing

Do some more reading about 3D printing, and follow this forum, and the google group more closely.

Happy holiday

Thanks Joergen. Merry Christmas to you.

I actually followed all of these steps when I was cleaning the parts. I had seen them listed on a few of the other threads about plugging issues. The one exception is that I couldn't use a heat gun to clean the teflon/nylon piece, as I don't own one.

I was very careful about making sure everything was seated properly during assembly and reassembly. I'm also wondering if this Ultimaker brand white filament might be bad. It doesn't seem to want to melt until it's 225c or higher. It is definitely PLA, but that seems high. I know it's not ABS, because there is no nasty smell. I'm going to clean everything one more time and swap to a different filament today, just to make sure.

Happy Holidays Everyone!

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Questions:

1) Do you have v1 or v2 hotend ?

2) Do you have an extruder drive with the plastic rub plate, or with the spring loaded ball bearing ?

The machine WILL work very well once its all together properly and has some adjustment, but

its not very tolerant unfortunately. So its very sensitive to assembly fitup.

It would be helpful if you would take a few pictures (can you reduce the size please ? Its very hard

to make much out of your previous ones as they are 3x larger than the view window...).

If its failing to extrude and stripping filament, is because there is too much force required to extrude. This

is because of a plug, a plug is caused by incorrect assembly, gap between bowden and PEEK and also

because of poor design (if you the the v1 hotend). However with correct assembly and some nursing, you

should be able to print some parts even with the v1 hotend.

If you are having plug problems I recommend disabling any retraction at all, until its basically working.

Retraction really exasperates plugging.

C.

Hi Snow, Thanks for the reply and Merry Christmas to you.

Answers:

1. Version 2

2. Spring loaded bearing.

Yes, as I said in my post, I knew it was a plug because everything was still in place yet the filament got stripped. I figured the only thing that would cause that is a plug. That's why I disassembled everything and cleaned it out. When I reassembled everything, it plugged again.

I was really wanting this thing to work first try, so here are the things I checked prior to the first print:

1. I made certain the bowden was pushed all the way into the nylon piece and the horseshoe was snapped in place.

2. I made sure the brass was oriented exactly as shown in the hot head assembly. As shown here:

http://wiki.ultimaker.com/Ultimaker_rev ... usion_head

3. I made sure the brass was tightened fully into the Peek.

4. I made sure the nozzle was tightened fully into the block.

5. I made sure the brass was tightened fully into the block.

6. I tightened the aluminum plate fully to wedge the top of the Peek between it and the wood.

7. I made sure the nylon piece was mated with the Peek.

8. During print bed leveling, I even used the card that came in the box as a gauge, as instructed in the WiKi.

Everything was tight and unlike a couple weeks ago, the bowden didn't pop out at all. I was actually pretty encouraged when it started printing. Then it stopped feeding and my heart dropped into my stomach.

I took the previous photos with my iPhone. That's why they were so big. I'll take a few more later and throw them on my desktop to scale them before I upload.

[Bowden tube pop unplugged the temperature regulator]

Happy Holidays to all of you who've tried to help me this past month!

The heater finally arrived. Fed the wire through the machine and plugged it in. I had already taken everything apart and replaced all of the printer head pieces. It's brand new bowden, bowden clips, new peek, new aluminum block, new brass, new sensor. It was all assembled correctly and checked half a dozen times, because I've had lots of time waiting on parts. I had even disassembled the feed mechanism and double checked that it was all assembled correctly while waiting. Clips are all in place. Blue horseshoes are attached. After installing the heater, I ran through the calibration routine on the wiki to make sure it was aligned and the bed leveled.

So, I try to print a belt tensioner, because it's small. My Ultimaker lays down one layer, then part of another before it craps out and stops feeding filament. It had ground itself a half-moon shape into the side of the filament, but both ends of the bowden held firm, so the problem I had originally is fixed.

Still, from clean, brand new everything, it appears I got an instant plug. At that point, there was much foul language. I took the print head apart. There was only a tiny bit of plastic in the brass and nozzle, which I cleaned out. In fact, everything was relatively clean up to the white nylon piece that connects to the bowden. It was completely solid. Couldn't even tell where the holes were without a magnifying glass. (I was using Ultimaker brand white filament, which seems to be the same color as the nylon.) Tried getting the plastic out, but no luck. Finally, I put it into a vise and used a 3mm bit and my drill press. As usual, my bad luck held and the piece popped loose from the vise and got chewed. So, I assembled everything without the nylon piece. It actually worked better without it. It got a little further on the print before it stopped feeding. It still eventually plugged, though.

The sad part is, I can't even complete one print to make any parts that might help me get this damn thing working. I'm pretty fed up. At this point, It's been a month and I still don't have a single completed print. I'm not spending another $50 to ship another $8 piece and that wouldn't fix the plugging issue anyway. After spending over $3000 for nothing, I think I'm pretty much done with Ultimaker. Lesson painfully learned. If somebody with infinite patience wants to take this thing off my hands and fiddle with it until they get it to stop plugging over and over, I'm open to offers. I have the latest everything on it, some extra parts, and the extra Ulticontroller, too. I also regretfully bought the $200 NetFABB license, which I'm sure I'm stuck with.

Everybody I've talked to who has their Ultimaker working reliably has replaced the stock Ultimaker feed path with something different. Those who haven't replaced any part of the feed, are still getting plugs constantly. I just don't have the patience to clean out plugs 5 or 6 times a day while never completing an entire print. Doing it twice today with no improvement in plugging was enough.

Can anyone recommend a dependable printer with a large print volume and a stock feed mechanism which doesn't plug constantly?

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Ordered and paid for the parts yesterday, but still no shipment notice, and they already left for the day again. This means they went through a full work day after I ordered and they didn't ship it out. So, I won't see the parts until next week at this rate. That's one more week of useless printer. Ugh! Frustrating! :(

Update: Ordered Monday. Parts shipped on Thursday after I reminded them about my order on Wednesday. Had to remind them the first time I ordered parts, too. *sigh*

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It doesn't show up in the shop because they are support items, usually the support people will give you the links to the items so you can order them trough the normal channels.

Thanks man! They should give you a raise. You're more helpful than emailing support. LOL

Snowygrouch and MSURunner are more helpful, too.

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Ok, just found some more Ultimaker web site strangeness. When I tell the Ultimaker Shop to list all parts and accessories, there is no heater cartridge/cable listed. When I Googled for another supplier, it listed an Ultimaker shop page for buying it!! So, I just ordered it using that page. I hope it's the right one, since it cost E45 to ship the E32 item. That's one more drawback of buying from the Netherlands. I've spent over $500 on shipping alone. *sigh*

The item I just ordered said 40W 18V. I hope that's the right one. I'm stumped why it doesn't show up in the shop.

[Bowden tube pop unplugged the temperature regulator]

You could print at 185C, but VERY slowly. The speed of the Ultimaker makes it need higher temperatures. Start out with 230, and if that works, drop down to 210. 210C is what we always use at Ultimaker HQ.

Thanks Daid.

Any chance you know the price on the heater cable/cartridge, so I can send the PayPal to get it shipped? Got up extra early this morning to check my email and still no reply.

Alternatively, do you know someplace in the U.S. where I can order it? (or any other parts for Ultimaker) This time difference is crazy frustrating.

[Bowden tube pop unplugged the temperature regulator]

My saga continues. There was a problem with me communicating my parts order. I originally asked for the long white wire that goes from the Arduino to the aluminum block. Not remembering the name, I accidentally later referred to it as the thermocouple, which was obviously incorrect. The parts arrived a couple days ago and the long white wire that goes to the Arduino wasn't in the order. Instead, there was a short thermocouple wire. Going to keep it as a spare. The other items were right, though. Since it's been over 2 weeks since I got the kit with nothing to show for it, and I will now have to wait another full week for parts, I emailed my annoyance. Then, I looked back at my emails and noticed my confusing description when I originally placed the order. So I emailed again to tell them it was my fault. I said I was sorry for the mix-up and just to send me the correct wire (heater wire) as soon as possible. I asked them how much money I should send via PayPal, so the order could get out the door. I'm guessing nobody answers emails on the weekend, because I haven't heard back on price since I sent the email on Friday. It's Sunday night.

This time difference is killing me. If I answer their email at 8AM my time, they're already gone for the day. When they get in, it's the middle of the night here. If they ask me a question, I don't get it until 8 am the next day, which means they're already gone again. If any prospective buyers are from the west coast U.S.A. timezone, be warned that your emails always take 24 hours minimum to get a reply. It works like this: Monday morning 8 am send email. Tuesday get an email back. Immediately send reply. Wednesday get email back. Send reply. Thursday get email back. If you send one Friday morning, you don't hear back until Monday, which really hurts. One email per day can get very old when troubleshooting. Speedy turn-around is just impossible unless you stay up until 2am to contact them.

Anyway, I went ahead and assembled the things I could and now I'm just waiting for them to ship me a heater wire, which probably won't happen until Tuesday, since I'll get the reply with the price on Monday morning and they'll already be gone for the day. *sigh* I already contacted Type A to buy one of their dual-extruder machines. Maybe I can make some parts with that one to get this Ultimaker working.

[Bowden tube pop unplugged the temperature regulator]

Just a quick update. I'm still waiting for the parts I ordered last week.

In the past few days I took the head completely apart and carefully checked the Wiki instructions again. I also examined each part carefully. I figured out what caused all the problems. The cause was that I followed the instructions perfectly. The instructions told me to use the top marked 8A. So, I did. When I finally forced the Bowden tube through the gray plastic with pliers (it was extremely difficult), I damaged the gray plastic part. This is because I followed the instructions and the instructions are wrong. I figured out yesterday that I was supposed to use the unmarked top piece which has a cone shaped hole for the gray plastic part to expand outward during insertion. The instructions told me to use the marked top and I did. The Wiki is also wrong about which direction to install the restraint for the temperature regulator wires. If the instructions showed the correct position, the plug wouldn’t have unplugged. So, the temperature wouldn’t have hit 460C+ and I wouldn't have melted my build platform, my Peek, and part of my fan shroud.

In addition, there are no instructions on building the PLA spool holder and no guidelines for the perfect settings for printing with Ultimaker's brand of PLA. I basically left my test prints set for 225C, which was the default in Cura. I've seen other printers advertise that 185C is good for their PLA. Anyone know what settings work best?

Having better instructions would probably solve 99% of the many problems people have listed on the forums.

Anyway, I guess it was my fault for following the Wiki V3 instructions exactly. Those instructions need to be updated. I won’t follow the instructions next time, since they are incorrect and incomplete. I understand how the printer is supposed to work, now. I'll be better off without the instructions.

I'll keep you posted after I get the parts and rebuild the printer. I'm guessing I won't have any issues this time around since I figured out where the instructions were wrong.

[Bowden tube pop unplugged the temperature regulator]

For those who asked for pictures of my filament. This is what it looked like when I retracted it out of the Bowden tube to have a look.

According to my digital caliper, the filament on the spool seems to hover around 2.86mm give or take 0.01mm. When I was trying to print, I had already adjusted this value in Cura. Unfortunately, I never got more than a few layers printed before the Bowden popped, until I finally screwed the Bowden in place. Of course, finally getting it to stop popping was long after the Peek/build surface/fan shroud/brass tube meltdown, so I could finally print more layers, but they were messed up by the massive leakage, so it was moot.

Anyway, the filament moves through the tube fairly easily, but with noticeable scratchiness/vibration. Once I pulled the filament back out of the tube, I could see that the feed mechanism is chewing up the filament a bit, which explains the vibration. The rim of the tube is catching on rough patches as the filament enters the tube. Once I get it working with all of the stock replacement parts, I'm going to print the parts to switch to a 4mm/6mm Teflon tube. Already picked up the tubing for it.

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After removing the remaining pieces of the crumbled Peek, I noticed the brass had cracked badly inside the melted Peek. This was the source of the brownish plastic oozing out from the bottom edge of the Peek. I cleaned out the tip and aluminum block while they were hot and then tried to pull the thermocouple out of the block to set the metal parts aside. Of course, the heater had welded itself in place during the meltdown, so the wire came off and the heater is in the block permanently.

When I step back and look at this sequence of events, it just boggles my mind that this entire chain-reaction of printer self-destruction was started by something as simple as Bowden pops. The single pop that caused the meltdown created a seemingly unending string of problems for me. I got a reply from Ultimaker this morning. They told me to just buy the replacement parts and fix it. They seem to believe I'm retarded or something and that I caused all of this myself. My actions were all in reaction to a poorly-designed Bowden retention system. I mean seriously, a glorified plastic grommet and a little blue horseshoe is their retention system for a system which pushes solid filament through a tube?!? That's weak, at best. The forums have a bunch of posts about people having the same Bowden pop problem. Mine just escalated further than others'.

Anyway, I'm stuck waiting for a couple hundred dollars worth of parts to arrive so I can basically build a brand new print head and try again to make the Bowden stay put. Needless to say, I won't step away to take a phone call for 10 min during test prints this time around. Bowden pop = temp sensor pop = total meltdown. I learned that the hard way.

[Bowden tube pop unplugged the temperature regulator]

The Peek just crumbled apart. It was deformed so badly that it wouldn't come off the brass. I need to order some parts before I can proceed any further. Thanks for all of your help guys. It looks like this printer is on hold until I get the parts. I can't wait to join you among the happy ranks of fully functional Ultimaker owners.

[Bowden tube pop unplugged the temperature regulator]

PLA shouldn't be a problem. First, I would flip that comb (black F-shaped thing) around so that the f is covering that socket and holding the temp sensor into the board so that if you do get another plug and bowden pop it doesn't pull the sensor with it. Second, can you post a picture of your hotend? There can be some confusion in assembling the hotend on the v2 (new ones) and if incorrectly done it will lead to a blockage and plug almost every time. Third, have you gone through the first run wizard in Cura? That will get you close enough on your steps per e that you shouldn't have any problems. You can get some issues with that as the extruder is either under or over extruding which will lead to plugs from the material not getting forced out quickly enough and thus flowing upward into the PFTE/bowden junction or grinding of the filament followed by a plug (respectively). If you can upload a pic of your filament, that can aid in the diagnosis. Also, you should be able to slide the filament (with a clean cut end, not a mangled end from a previous print) through the bowden with ease. If you can't, measure your filament with some digital calipers. If they are 3 mm or less, measure the inside of the bowden, if you still can. The bowden should be close to 3.1 mm. Sander at UM is going to probably want those measurements if he's going to send you another bowden. Chin up! You'll get it working !

I'm using white PLA purchased with the machine from Ultimaker. I ran through all the steps in the Cura wizard. Everything checked out fine. Here is the hot tip photo:

Based on what you're saying, I think my first couple Bowden pops (out of 50+ pops over the past week) and/or the Peek melting must have created some plugs in the feed path. That meltdown also melted a deep pit in my build platform, but I flipped it over to use the other side. My temporary fix for the Bowden was to put a screw through the wood and into the side of the tube. Here is a photo of that:

The Bowden doesn't move now, but it has created a new problem. The extruder is grinding the filament and unable to feed after a couple layers are printed. This again, supports your plugged feed path idea. If the Bowden isn't moving, then something else is preventing easy feed (it's not the screw, btw - double checked that it's not impeding the filament already). Also, there is massive leakage of brownish (burned?) plastic coming from around the brass/aluminum joint area. I figured it was because of the melted Peek but maybe that's another symptom of blockage? Would the leakage stop if I find the plugs?

Bottom line: I guess it's time for me to disassemble the print head to look for plugs.

[Bowden tube pop unplugged the temperature regulator]

Get in touch with UM. I had a run away on mine that was a result of the same problem and they replaced the PEEK for me. Given your troubles, they may provide you with an additional bowden. Also, check to make sure you have the comb part on the top of the print head over the amplification board DIRECTLY over the three prong socket. I believe the Wiki had it reversed at one point (maybe it still does).

After that, figure out why the tube is popping. The most common instance would be plugs forming at the PFTE to bowden. I would be sure to check your retraction settings, if you are using retraction, as you may be pulling molten PLA up into the PFTE piece, thus creating plugs. The next thing I would check too is that you aren't over tightening the four cap bolts that hold the print head together. I think that's a VERY easy thing to do because we are all worried about it leaking. In reality, this can overcompress the bowden, which can create plugs. There is not a lot of force necessary in tightening those four long screws to provide a leak free unit. The other thing I would check is that you haven't applied too much pressure with the extruder to deform the PLA as that can cause a plug as well. This is much more rare on the spring and bearing extruders. Then, consider printing faster so as to push the filament out quicker, thus not allowing as much of a molten PLA build up. Conversely, you could lower the temp you are printing at. Finally, consider active cooling.

Took your advice and sent support an email about my problems. Hopefully, they can help me get a print head that works as advertised without constant fiddling.

Another question: I'm using white PLA filament and the objects I'm printing out seem rather fragile. It feels like parts made of rice cakes. Is that normal? The crumble so easily, I don't know how they could be used in a real device. Maybe I'm using the wrong plastic. I just liked the bio-friendly aspect of PLA, but don't want to give up durability. Should I be printing with another type of filament?

[Bowden tube pop unplugged the temperature regulator]

Finally yanked out the clamp up top and just put an M3 through the wood and into a hole on the side of the tube. Here is a pic of my butchered print head.

It's ugly, but it's finally printing. Having trouble with globbing and brown ooze above aluminum block now. Been playing with settings to try to fix those issues now.