I and getting tired of repairing my feed assemblies

[Joe Larson (aka Cymon)]

I am getting tried of fixing my nozzles. Thank heavens I have two. But I repair one and the other one is broken. At the moment I have a flash forge with the PTFE on the left and it's nozzle is somehow super clogged (filament is clicking when it feeds through and it's coming out in spirals) and the left one is just a little loose resulting in some leakage. At least the left is good for small print jobs.

Is there somewhere I can buy a new left and right nozzle, feed tube, and block for left and right? I'd be willing to go FF or Makerbot style, I really don't care, as long as it fits. The motors are fine, the heater elements are fine. I just replaced the thermocouples. But if someone can suggest something that will mean I won't have to do do repairs every other day I'm open.

[Ryan Carlyle]

You can buy an entire new dual hot end + cooling bar + heater + TC assembly from the Flash Forge USA site. http://www.flashforge-usa.com/shop/extruder-assembly.html The pic doesn't show TCs but the one I ordered recently came with M4 brass thermowell type TCs.

But the PTFE tube setup used by clone printers is fundamentally a kludge for poor thermal management. It doesn't give maximum reliability. Personally I have trouble recommending you buy more of what's already giving you problems.

Carl's all-metal setup is really good if you're willing to drop some cash. http://shop.raffle.ch/ Get the dual carriage (to fit the larger cooling bar), dual cooling bar, two T-blocks w/ threaded thermal barriers, and pick up a couple nozzles from QU-BD or whoever. Note that you will need shims or new extruders to fit the thicker cooling bar. 

[WifiGuru10]

What plastic are you printing? ABS doesn't really need PTFE tubing but PLA does, otherwise it gets a little too soft if your running hot and can jam up.

I hated my MK7's, replaced the nozzles on a regular basis, constantly had to re-align the nozzles (have a dual) but ended up having to buy whole new heater blocks and starting again. Eventually gave up on the MK7s and replaced them with MF1's from MBOT3d, waaay better design. Haven't cloged once yet, only issue i had was the PEEK spacer coming apart at high temp but they promptly sent me a replacement. Going to try again once i get some better ABS/HIPS plastic.

Downside is they only sell the whole kit, but comes with springed extruder feeder, thicker bar, much better quality than the MK7/8 series. Still is a PTFE inner tube, but I honestly beleive that it works well, especially with PLA. 

If you want the cheap option, buy a whole bunch of MK7/MK8 nozzles on ebay, you can get 5 or 10 of them pretty cheap. Heat your extruder up to temp, pop off the brass nozzle and replace with new one. I had to do that every so often when i started having issues. 

If you want to keep using the printer for a long time, i'd suggest upgrading the extruder.

[Joe Larson (aka Cymon)]

I don't mind the PTFE tube, but I mostly print in ABS. It's worked good so far... for the month I've tried it out.

That mBox extruder doesn't look too bad, but does it not need insulation? After fighting the insulation and having prints fail when the insulation fails I'm not sure I can wrap my head around not needing insulation. Tell me more about this MF1.

On Friday, June 6, 2014 12:38:42 PM UTC-6, WifiGuru10 wrote:

What plastic are you printing? ABS doesn't really need PTFE tubing but PLA does, otherwise it gets a little too soft if your running hot and can jam up.

I hated my MK7's, replaced the nozzles on a regular basis, constantly had to re-align the nozzles (have a dual) but ended up having to buy whole new heater blocks and starting again. Eventually gave up on the MK7s and replaced them with MF1's from MBOT3d, waaay better design. Haven't cloged once yet, only issue i had was the PEEK spacer coming apart at high temp but they promptly sent me a replacement. Going to try again once i get some better ABS/HIPS plastic.

Downside is they only sell the whole kit, but comes with springed extruder feeder, thicker bar, much better quality than the MK7/8 series. Still is a PTFE inner tube, but I honestly beleive that it works well, especially with PLA. 

If you want the cheap option, buy a whole bunch of MK7/MK8 nozzles on ebay, you can get 5 or 10 of them pretty cheap. Heat your extruder up to temp, pop off the brass nozzle and replace with new one. I had to do that every so often when i started having issues. 

If you want to keep using the printer for a long time, i'd suggest upgrading the extruder.

Those  

[WifiGuru10]

The MF1 still has the internal PTFE tubing, but the exterior doesn't need the fiberglass wrap. Are you talking about the wrap? I'm just a user not a designer, but my take is that since it's a single milled piece versus two pieces (heater block, nozzle are seperate on the MK7) the heat transference is much better IMHO. Also they use the k-type thermistor and is embedded inside the heater-block for better temperature accuracy, the old MK7 i used had it bound up externally on the heater-block. So my take was the wrap helped insulate the whole block to better transfer temperature to the sensor. 

The reason i ended up replacing the whole assembly was because my old k-type thermistor failed (shorted to the block) which is grounded to the motors (via the metal tube) and blew out the mightyboard (cheap chinese knockoff). Ended up purchasing a whole motherboard/MF1 kit from makerbot. They use PEEK spacers for the heads, so no more having the level them (dual extruder). Also if the thermistor shorts, it's not grounded to the motors.

I haven't printed much ABS, but it's significantly better with PLA. I'm going to get a ABS spool here soon to test.

How did the insulation fail? Did it fall off or get stuck on the print?

[WifiGuru10]

Correction, purchased a whole new kit from MBot3d and retrofitted my CTC printer.

The other thing i can mention is that i'm seeing alot more stable temperatures on the MF1 tip versus the old MK7. Bigger swings in temperature and crummy quality filament can cause binds.

I've ordered a new ABS spool, i'll post some more reviews when i get some prints done.

[Joe Larson (aka Cymon)]

I had constant problems with failed prints binding up and sticking to the fiberglass wrap, and I've explored so many options for fixing it. My current solution is to use a woven fiberglass tape with a metal tape around it, as opposed to kapton, since ABS doesn't stick to it as well.

I'm still not convinced that I need everything the MF1 offers. My motors are fine. And I'm not sure how I feel about everyone so far not having any ABS experience. that's literally almost all I do.

[Ryan Carlyle]

Insulation is mandatory if you have an old "external" thermocouple that is just sitting between the tape and hot block. It is also recommended in general because heat radiated off the hot block can impact your print quality and eventually warp plastic carriage components.

Many people run fine without insulation but it greatly depends on the airflow around your hot end and construction of your carriage.

[WifiGuru10]

So what is your actual problem? Is it your prints not sticking to the print bed properly? Because your original question was regarding nozzles. If your nozzles get gummed up and spiral then it's probably your print head, if the print pops off the bed and gums up the nozzle thats a different problem.

I printed alot of ABS in the day and didn't have the problem sticking to the kapton tape, it was mostly just clogging the head and slipping on the drive gear. Do you have a spring loaded drive gear? The stock MK7 design doesnt' have any force applied to the filament, that would help alot.

I agree with Ryan says, insulation is mandatory with the MK7 series, if you want a better head for ABS take a look at J-heads but you'd probably need to retrofit alot of stuff to get it working. The MF1 is a hybrid between the MK7 and J-head and is a drop-in replacement.

You might want to look at a bigger nozzle, something like a 0.5mm is a little more forgiving with ABS. Also look into spring loaded drive gears to get better force on the filament, that should help with the extruding problems. That should be the first mod you make.

Take a look at http://www.thingiverse.com/thing:42250, thats the one i used and worked wonders. You can also find pre-made kits on ebay if you have problems printing it.

[Joe Larson (aka Cymon)]

My original problem is the nozzles. They're jammed and possibly deformed. For the umpteenth time. My old blocks are stripped or gummed up so I bought new ones from a guy on eBay and they're all sorts of wrong. And my one feed tube is bent. So i basically need to replace everything that apparently is sold in this thing: http://www.flashforge-usa.com/shop/extruder-assembly.html with the exception of the heater elements and thermocouples.

How easy is it to install this thing: http://www.flashforge-usa.com/shop/extruder-assembly.html in a replicator 1?

[Jetguy]

Joe, if you are going that route and already spending $135 plus shipping, it's cheaper to buy and entire extruder from Wanhao USA that has the motors, drives, everything for the same money with free shipping from Florida

These seriously work and I also like the filament drive sections,

http://wanhaousa.com/collections/parts-components/products/mk9-dual-extruders-black

[Jetguy]

BTW, I know for a fact this is drop in ready!!! EVERYTHING matches up exactly, Simply drop in and attach the wires to the mainboard. The stepper motors are genuine moons, the filament drives are some of the best I have used.

I'm trying to save you a buck and some headache.

[Jetguy]

Also, for those ticked off at a Replicator 2X that doesn't print PLA, This is another drop in option for you. Yes, you have to use the tab style thermocouples but the motor wiring is plug in, the heaters are 24V ready to plug in, the filament feeders are better and so forth.

Again, quality drop in extruder for $155 and free shipping. Damn hard to beat.

[WifiGuru10]

The extruder assembly is ridiculous easy to replace if it comes like the picture. There is two m3 screws holding that bar to the x-carriage, just access them from below which will pop off the whole extruder/nozzle/motor bundle. Then just remove the two fan m3 screws (the lower ones) on each extruder, they go through the bar and screw into the stepper motors. Then just take apart the wiring that leads to the mightyboard and you should be able to replace it. The one thing that flashforge doesn't have is the thermistor, so you'll have to transfer them from your old set.

Have you got an upgraded delring extruder/plunger yet? If you have the stock non-spring version, i highly recommend you get one. It'll keep more force on the filament and keep it from slipping which can cause poor prints. Anyone and everyone will recommend them on this group, makes a world of difference. You can even print your own (link i provided earlier) and purchase the bearing/spring set from makerbot for like $8.

[Joe Larson (aka Cymon)]

Only problem.. sold out. I would do this right now if they were in stock.

This is monumentally frustrating to me right now. My right extruder is extruding mini springs and my left extruder just jammed too. I am so tired of fixing this, and I have some big jobs that are waiting, not to mention a lot of little jobs. I want to get back to printing. But now I can't. And the solution, dangled in front of me, is out of stock. I could cry.

[Jetguy]

Chrome version in stock (just the fan grill is chrome http://wanhaousa.com/collections/parts-components/products/mk9-dual-extruders-chrome

[Joe Larson (aka Cymon)]

I just saw that. Was going over the two of them with a fine toothed comb to make sure they were, in fact, the same thing, and placed the order. Once again, Jetguy, your expertise is my salvation.

[Ryan Carlyle]

Jetguy, which drive gear do those use? Does the diameter match MBI's? Not a huge deal to fix with packing density or A axis steps/mm but worth checking.

[Jetguy]

It is a super fine tooth and very sharp flat cut gear but yes, the same effective diameter as the MakerBot one. I know this because I use bone stock profiles and stuff and never had to calibrate using a default Replicator 1 profile.

They use a V roller bearing to guide the filament on the flat gear.

[Jetguy]

When I say profile, I mean say in S3D, or even using Makerware,, or Rep-G, you can use the default Replicator 1 settings and it's perfect, no change too packing density, steps per mm, or anything else is required.

[Joe Larson (aka Cymon)]

Got the wannaho extruder heads. Tried installing it. The connectors aren't exactly the same. In fact the wires came  in their own connectors with labels and everything. So I thought I could remove the connectors on the board and use the wanaho ones.

Clearly I have no idea what I'm doing.

Makerbot's connector was considerably more attached than wanaho's is. Destroyed 2 of the pins.

And suggestions? I'm thinking if I could get pins that the wanahoo connectors are compatable with I could solder them on to the board and plug and play. May even do that with the other two that I need to install. I'd hate to abandon those neat labeled connectors.

http://wanhaousa.com/collections/parts-components/products/mk9-dual-extruders-chrome

[Jetguy]

I posted an email but step 1 is simple use a screwdriver and remove the connectors on the Wanhao wires, you never had the mating connector. Not sure why you ripped off the screw terminals as a solution but hey, we all have those days (need the bigger hammer) so please, don't take that as a knock. I'm only ribbing because we ALL have destroyed something at least once.

That said, there is hope.

Personally, I use the RadioShack desoldering iron. I know, some guys like braid but for me, this is my go to tool.

Step 1 get this tool http://www.radioshack.com/product/index.jsp?productId=2062731
$14 from radioshack. Trust me, this is my most used tool ever.
 
Step2, get replacement connectors
http://www.radioshack.com/product/index.jsp?productId=2102861
 
 
Hopefully you also have a soldering iron and solder handy. If not, get them too.
 
My radioshack ALWAYS has those both on the shelf.
 
Then you have to take the motherboard out and use the desoldering tool, let it heat up for at least 15 minutes, then flip the mainboard upside down,  and locate the underside where that connector was, there are 4 pins and solder pads.
Squeeze the air out of the red rubber bulb and hold it squeezed, then  place the hollow tip over the pin slightly sticking out. Let the heat flow into the solder joint an melt it, now release the bulb and let is suck the solder from around what's left of the pin. Hopefully it does this on the first try. If not, I know it sounds crazy, but use the soldering iron and ADD fresh solder to the pin and then try again. The reason is the new solder on boards is all tin and no lead. It requires higher temps and doesn't flow well. Adding a lead based solder reduces the melting point and lets the solder sucker get all the solder all the way through the hole letting the pin drop and the hole is then clear and clean.
 
Then simply solder in the new connectors.

[Jetguy]

FYI, for those following, let's say you are motivated like Joe and just rip your connectors off the mightyboard.

Ok, so you want to use pluggable connectors and that's not the worst idea so we roll with it.

So use the above instructions to desolder the screw terminals and replace with either of these.

https://ultimachine.com/content/fixed-terminal-block-4-contacts
 
or digikey http://www.digikey.com/product-search/en/connectors-interconnects/terminal-blocks-headers-plugs-and-sockets/1442750?k=1757268

[Ryan Carlyle]

Yeah, all you had to do was unscrew the connectors from the new part wires and connect the bare wire ends to the screw terminal on the mightyboard. But if it makes you feel any better... last month I tried to replace the connectors on a FF clone mightyboard with Replicator style screw terminals, but ordered the "internally jumpered" version in accident. So I soldered these connectors to the board and they dead-shorted the outputs on all the FETs. When I powered up the board, it immediately fried the extruder fan FET and let out all the magic blue smoke. Burning out the FET left 24v shorted directly to ground so my PSU went into overload mode and wouldn't turn on at all. I spent HOURS trying to figure out what happened.

Freakin' Digikey didn't label their terminal blocks clearly enough, that's what happened.

[WifiGuru10]

Yeah, he shouldn't of tried to modify the board, easier to replace the thermistor wires than it is to desoder/resoder connections. If you don't know what your doing, or don't know how to soder, get a friends help that does. You can easily make things worse and damage the board. Great way to learn is to try on some old broken boards, practice first before doing this on the mightyboard. 

Joe, make sure your comfortable with sodering/desodering before doing this. I highly recommend using heatsink clamps (http://www.newark.com/gc-electronics/9077-1/heat-sink-clamp/dp/95F2281) something like that is also available from radioshack, that way you can make sure you don't overheat the board and damage something else. You'll also want to completely remove the board from the printer, that way you can get at the bottom of the board better.

[Les Jones II]

You can also get the Wanhao Dup 4 replacement dual head (complete) setup from: http://3dprintersolutions.us/.  I got my printer from Carl and also a spare dual head (which I have not had to use yet). Problems very minimal, but I print almost exclusively PLA so far.  

[Jetguy]

While normally I agree, in this case, the advice on the heatsinks is incorrect. If anything you need ALL THE HEAT YOU CAN GET.

 

45 watts is just enough to desolder the ROHS solder used on the through hole pads. This is why I said I sometimes, especially on the ground plane where BOTH sides of the board are heatsinking the hole, I have to add 60/40 lead solder just to jet enough heat and a lower melting temp so the entire depth of the hole is melted and the solder can be cleanly removed. This is why I find braid to be innefective for this particular fix.

 

I do this exact mod on Flash Forge boards to install screw terminals rather than the plugs. I've probably done 10 or more boards at this point and I can say with no doubt there is little chance of damaging with heat. If anything you may not have enough heat.

[WifiGuru10]

What i meant was to use the heatsinks on components that are close to the connectors so it doesn't transfer heat to the other stuff. Is this not the case Jetguy? I defer to your wisdom of course, just have fried a couple components back in the day so usually do this to protect the other components.

[Jetguy]

In this case, the connector was destroyed. he's just trying to clear the through hole in the board to be able to solder in a new connector.

the copper planes on both sides of this board suck away the heat so fast it truely is hard to remove the original ROHS (Reduction of Hazardous Substances) lead free solder that is present in most electronics. Hands down, one of the worst enviromental disasters of all time.

Some complete moron decided that lead in solder was bad (proven over and over it's NOT and does not leach out in landfills) and made them remove all lead from solder in consumer electronics. As such, the solder these days is mostly tin and causes tons of failures. FYI, remember the Toyota uncontrolled acceleration recall and disaster? Root cause, ROHS solder and coatings that then grew tin wiskers that shorted the throttle potentiometers WIDE OPEN.

So all those bad electronics board that now fail because of bad solder now FILL landfills. Wasn't the goal to have relaible electronics that last and do not fail causing safety issues? Hmm, not too hard to see how wrong this has gone.

 

We call this the worlds most EPIC backfire but you don't hear about this on 60 minutes.

Truth be told, most of these enviromental laws cause more damage than they ever solved. It's money changing hands, not about the environment.

Should be criminal what they have done.

 

Sorry for the rant.

 

Back to this problem, you cannot put enough heat from even a 45 watt iron to damage a single component. When I do the penny trick to swap 1280s for 2560s, I have to use a 175 watt solder gun and the tip is glowing red hot heating the penny and giant solder blob and I have reused a removed 1280 that tool that kind of heat on every single pin into the body. They are tougher than you think and part of that is related to the ROHS rant from above. Modern surface mount electronics are baked during the solder process and are designed to take insane amounts of heat.

 

Nothing wrong with being cautious and yes, you were tought those rules (so was I) back in the days of not to long ago. It's just changed a bit and now everything is high temp. I'm being serious, it takes effort to damage from heat these days.

[Scott K]

Just a clarification to save some headaches for the R2X crowd wanting to use the Wanhao extruder assembly on their machines.  If it is the same as the FF extruder assembly (meaning the cooling blocks mounting holes to the carriage), it will not fit your stock R2X carriage.  I am pretty sure the Wanhao and the FF use almost identical components.  I have purchased several of the extruder components and they are drop in with each other.  The extruder mechanism is also nearly the same as the FF and as Jetguy states, it is awesome and nearly bulletproof.  Haven't had an air print or jam in 1200+ hours.

Here is a FF extruder, you can see they are almost identical with the V-bearing as well.

How do I know?  I bought one and tried it.  The mounting hole spacing is different and the width of the bar is different also (but that wasn't a problem).

You will also not be able to "drop in" the wiring for the cartridge heaters because they are integrated into a single connector linked with the stepper motor wiring.  Sure, you could splice into the existing wiring, but don't expect to have a nice removable connector like the R2X has stock.  If Wanhao uses 6mm holes for the heater cartridges, you won't be able to use the MBI ones to preserve the stock wiring because they are 6.35mm OD heaters on the MBI.

I know all this because we tried to go this route to convert our R2X into a better PLA printing machine.  In the end, we just bought Carl's dual block and bought some genuine MBI threaded thermal barriers and nozzles.  Been printing PLA wonderfully for months now and don't have to worry about a PTFE tube inside the nozzle going bad with higher ABS temps.

On Friday, June 6, 2014 9:21:21 PM UTC-5, Jetguy wrote:

Also, for those ticked off at a Replicator 2X that doesn't print PLA, This is another drop in option for you. Yes, you have to use the tab style thermocouples but the motor wiring is plug in, the heaters are 24V ready to plug in, the filament feeders are better and so forth.

Again, quality drop in extruder for $155 and free shipping. Damn hard to beat.

On Friday, June 6, 2014 10:15:52 PM UTC-4, Jetguy wrote:

Joe, if you are going that route and already spending $135 plus shipping, it's cheaper to buy and entire extruder from Wanhao USA that has the motors, drives, everything for the same money with free shipping from Florida

These seriously work and I also like the filament drive sections,

http://wanhaousa.com/collections/parts-components/products/mk9-dual-extruders-black

 mean I won't have to do do repairs every other day I'm open.

[Scott K]

I should have included this in my last post but if you want to use the extruder assembly from Wanhao on your R2X, and make it nearly drop-in, you could buy the carriage from them.  It is only $18!  Wish I knew about that when we were upgrading our R2X.

http://wanhaousa.com/collections/mounts-and-molds/products/dual-extruders-carriage

You will still have some splicing to do but that is not too bad for gaining PLA printability on the broken R2X!

[Joe Larson (aka Cymon)]

Here's where I'm at right now:

http://joes3dworkbench.blogspot.com/2014/06/fixing-bot-by-breaking-it.html

[Joe Larson (aka Cymon)]

And I'm back http://joes3dworkbench.blogspot.com/2014/06/back-in-business-mostly.html

Mostly. Still having first layer troubles. Going to try tightening up  the leveling and maybe trying a raft. We'll see what works.

The problem with the first layers are, first of all, they're shrinking. Secondly, when the print is done what hasn't shrunk is stuck fast to the build plate and damages the print when it's removed. I've never seen this one.

[WifiGuru10]

What you need is some kapton tape or ABS juice if your printing ABS. That's why your first layer keeps popping.