gixxer

I'll give UHU a try as 3dlac seems hard to get hold of in the UK. I did rob the wife's hair spray to take to work this morning though. Didn't get the time to try it out though. I read somewhere it's supposed to work well for ABS prints.

Ok here are some are some pics of the heater block install. Sorry about the blurry image. I had to extend the slot for the cartridge clamp by hand to gain enough pressure on the heater and temp sensor. Here you can see the 3mm hole for the M2 clamp bolt. Something which I missed in my design originally that Anders pointed out. This prevents the heater block from rotating. Inevitably the design is very similar to that of Anders one but there are little options if you want to be as plug and play as possible. The only significant difference is in the heater clamp. I've had limited time to test but did give the 0.8mm ago, which I was surprised to find required lots of adjustment flow control. Great on the solid first few layers at about 70% flow then had to increase to 105% for the walls. However this was on the sprialize mode. Tried a 0.4 next which considering the filament I was using which I'd had so many problems with in the past, it worked very well. Nice glass like top surfaces and great flow even at temps of 210 (50mm/s). That shocked me the most. Previously to get a solid top surface with the light blue UM pla I'd have to slow it down and run at 255+ with 110%+ flow. I hope to get some pics of prints Monday. Just to note. I don't have any intention of selling any blocks as Anders if very similar. If ether Anders or Swordriff want the Inventor or pdf files to make one or sell many I'd be happy to share.

Just received my first prototype heater block! Fresh out the machine shop. Had to make one adjustment off the drawing but worked really well. Haven't had much of a chance to test it in anger yet but the first thing I noticed was how much I had to lower my temps! Using the light blue PLA ultimaker filament which has always been a pain for underextruding at anything lower that 255, I was having to go down to 220! Will hopefully post some pics later off the block and the fan mount mod. With some pics of some prints to follow on Monday.

I'll give that 3dlac a go. What's the bed release like?

Hi Robert, I do remember Anders saying that R&D had one. Would love to know how they got on with it. I'm eager to know as as my design should be ready by Friday and is very similar with I think a marginally shorter melt zone. Hope it turns out as good as what we've seen here from Anders one. Do you know how the R&D team got on with it? Really think that the future nozzles should allow you to change the tips. I can see though why ultimaker would go down the road they did though. Sell something that works well overall and keep the margins down. Guess I want ultimaker 2 reliability/quality but have the mod ability of the original.

Hi Nalfy, Are you having issues with bed adhesion or warped parts. I was just about to start a new post for a bed adhesive called CubeX magic stick. I'm in the UK to and recently started to print ABS on the um2. Been having some bed adhesion issues myself using glue stick at 110c bed temp with large brim. Works somewhat Ok with some lift but that's on 20+ hour prints. I also have an enclosure. Any how this CubeX stuff sticks like crazy! The problem is getting the Dam thing off. Apparently you have to soak the glass bed and part in some warm water for couple on min and it dissolves the glue. I've not done this as I don't have easy access in my office at work to a sink. I've decided to back to the pritstick for the moment and save the CubeX for really problem prints. You may want to give it a go thought if you can put up with getting your print off the plate. Create3d sell it in the UK at least that's where I got it from (£15 for 2). Edit*** forgot to mention room temp is about 20c.

That's a clean print for a 0.5mm layer height meduza . Am I right in guesstimating that you could go as hight as 0.65 ish? Also can you still achieve heights of 0.1 and lower with good results?

Hi gr5, do you mean no different in flow, oozing or both? 18mm^3/sec that's impressive. This is one of the reasons I'm having a block machined. Any idea what layer hight one can achieve with a 0.7mm nozzle?

Sorry "swordriff" Dam predictive text!

Hi swordfish, Yes I see where your coming from. Don't forget though that the Anders design also corrects a poor design (I hate to speak bad of my UM2) on the standard block, the grub screw clamp that holds the heater and sensor (as I found out today). Those that do make the switch to Anders block would also only have to change the nozzle tip rather than the whole block. Do you know if any tests on oozing have been done yet? Think it was mentioned previously that the flow should be improved due to the longer melt zone. I know there are quite a few on the forum that has suffered with underextrusion that my benefit. Do you think you could be in a position to look for others to stock this mod. Perhaps E3D? Would be a shame for it to only be available from the forum.

Warning to anyone thinking of changing there heater block even for the standard one. Changed my one today and could not get the temp sensor out without pulling the wires out of the metal cap! The grub screw that holds the heater and sensor in had deformed the metal cap on the sensor and it wouldn't budge. Likely I'd already ordered a spare! So if your thinking of changing the block for a stock replacement or Anders one bear in mind you may not be able to get the sensor out in one piece. However if you do change to Anders block you shouldn't have any problems in the future as his design doesn't damage the heater/sensor casing. I took some pics while I changed the sensor so if anyone wants a how to I'll post one.

Hi Chris, I like the simplicity of you take on Roberts design. Could you give us some more info please. How many hours have you been using it for? Have you had any failures yet? Had to print my one in nylon as I had several failures in PLA. Have you tried printing with any flexible filaments yet? What parts have you used? I'm looking to get one machined in aluminium but really like Roberts quick release functionality.

OK version 3 straight off the press. First off I feel I must apologise to Anders as the design looks to be a complete rip off of his. However there really doesn't seem to be many other options without further modifications to the fan mount. I have come up with a solution to the heater and sensor clamp. The block thickness has been increased be 0.5mm. not much but I wanted to get the nozzle in as deep as possible to allow for greater heat transfer. The thread going to the cold block has lost 0.5mm height and the diameter beneath has been reduced to 4.70 from 5mm. I hoping this will reduce heat transfer to the cold end all be it marginal. The plan with the clamp at the back of the block is to run an M2 through into a hole in the fan mount. This should fix the heater and sensor in place as well as preventing rotation of the block. It should also reduce heat transfer to the cold end heat sink. I was also thinking of mounting small heat sink to the cold end plate. Thought this might increase the life span of the Teflon insert. Have at it people, cruel to be kind an all that!

Hi PowerCell, I hope your directing this request to Anders as I've not even tested my design yet.

Just found this also http://www.google.com/patents/EP1188535A1?cl=en Take a look at the sketch. I wonder how much research has been done on the internal geometry of our nozzles. Another option could be an enlarged cavity within the melt zone. I'm hijacking this thread now aren't I. I'll start a new one me thinks. **Edit** New thread for nozzle geometry added here http://umforum.ultimaker.com/index.php?/topic/8732-research-into-internal-nozzle-geometry/

Thanks Anders that's exactly the feedback I was hoping for. I hadn't given much thought to the corrosion resistance factor. I did some googling and found that the plastic extrusion industry uses tool steal for there nozzles but then they don't have retractions to contend with. The prices seem relatively comparable to our nozzles. I work in the atomized alloy powder business. We actually supply many 3d metal printing company. I asked about the brass as I have access to some rather exotic alloys, some of which are very thermally conductive. I'm not suggesting at this stage that these materials would be commercially viable alternatives right now but its something I'm going to look into ( I keep you posted on this one). - I am having both M6 threads thread milled in, but you are very right in this respect. Getting the thread to perfectly meet the sealing surface is asking for trouble. Milling out the last few mm it is. You are correct on another count with the 7.5mm depth, this needs to be reduced mmmm.... - I had not considered that the block would rotate without the set screw. I was wondering why it extended into the head sink. I'll have to think in this one but your solution in indeed a good one. I wonder with your design if having the screw on the bottom of the block going into a small hole the fan housing may be another approach. This should allow a much smaller screw reducing the thermal mass of the block further. - I did read the thread by Daid regarding the firmware change. I was hoping that given the sensor is so close to the heater cartage the 20 deg increase in 20 sec would be detected. I thinking that by getting the new nozzle deeper in the heat block there would be less temperature loss between the block and tip of the nozzle. There should be a way to calculate the maximum mass. I might try a few block sizes to see if I can trigger the error. This may be a very good idea not just for ease of machining but to reduce heat transfer up to the Teflon cold end. This section could perhaps be made from a material with a lower thermal conductivity. Hhmm... aim I missing something here or could that be another very good idea Anders? I can see that for the closest plug and play solution for interchangeable nozzles you end up with your design. I wish I'd have found this thread sooner now. Going off on a bit of a tangent, has a tapered internal profile be considered for nozzles before. If the taper ended at the cold end would this not reduce clogging particularly for all metal hot ends. From what I can gather the problem with all metal hot ends is that PLA during retraction acts like the seal in a syringe, as the filament is pushed back in it mushrooms and binds to the walls. However if the melt zone was tapered from 3.2mm to say 1.5mm the head of the retracted filament would also be tapered, reducing the likely hood of a clog. Just a thought perhaps my logic is way off on this.

I agree with you. The less modifications from the standard the better. Out of interest why do is the heat block made general of brass other than the obvious easy to machine, cheap, reasonably high heat conductivity. Is conductivity the main aim or does heat capacity also a large factor? I'm a little impatient and have easy access to machine shops so would like to get some blocks made my self. Plus I don't have to pay as it's for work

Hi everyone, I've been tinkering with this idea for a while now and came across this thread. I'm in the process of getting a new heat block made to fit the E3D nozzles too. I've attached a drawing of what I've had in mind but I'm starting to think this one would be better. Edit: When I say this one I meant the one by Anders Olsson. My design would require modification to the fan shield/mount though. I've increased the size of the block to accommodate the new nozzle which also gives room for M2 grub screws to lock the heater block and temp sensor in place. Please forgive the drawing its my first attempt with inventor and I may have one to many dimensions I have to admit that I'm not sure how the larger mass of the block will effect extrusion though. I know the heat up time will be affected but unsure about stability. The plan was to lower the fan mount and increase the hole size to fit the new nozzle. I'd really love some feedback good or bad.

I'm running 14.09.0. I've only ever run from SD card. I have tried going in to the retract menu while paused, tried adjusting temp and flow but it still shows "pausing..." on the display. I might try a reset see if that solves the problem.

I've only had my um2 for a month or so now and as used for work I've the luxury of ordering many different types of filament to experiment with. The one thing I've noticed is that there are vast differences between brands and especially colour within the same brand. So I don't think it's especially hardware related but more the feed-stock you use. That's not to say there isn't improvements that can be made but, let's remember that we are not dealing with company's here that have millions to throw at R&D (which would then undoubtedly be closed source). I'm sure if you where to purchase a £20,000 commercial printer using there proprietary filament the number of variables when printing would be vastly reduced. I'd like to add at this point that from the research I've done the Ultimaker2 seems to be one of the most reliable printers out there at this price range. Let's also acknowledged that the flow rate (layer height, nozzle size and speed) we print at dictates the temp we use. Having said that I've never had good results printing as low 210 as some people on here seem to. Perhaps if I where to go as slow as 20mm/s but I don't have quality issues at 50 so why go slower In an ideal world some clever person needs to develop some sort of flow matrix that would adjust the temp and feed rate dependent upon the chosen speed. However with variability between the different filaments and even the individual printers this would be very difficult.

Update for the bearing u groove mod. I've done two days straight with ninjaflex now and no problems. However............. I left a PLA print run last night only to find that at some point the filament snapped in the feeder. Looks like the printed u groove got pressed against the drive and rolled with it for a while until the retractions started and then ground a nice groove into the surface. After some investigation I found that the filament snap was not a feeder issue but a filament one. Thought I'd try some filament from Verbatim which was going really well but as you can see the last third of the spool has cracked all the way up the feed tube. Even as I try to uncoil it by hand it snapped in several places.

I've had this problem from time to time. I've only noticed it with PLA and some filaments are more problematic than others. There's a light blue from colourfabb that was particularly bad. I've found that I've always been able to overcome this issue by going hotter and increasing the material flow from 5 to 35%. I find that I have to print at 230°C minimum and as high as 250°C. Print speed is never slower than 50mm/s. Nicolinux I did see in a previous thread that you'd increasing temp and flow with little improvement. It might be worth oiling the pla as it enters the feeder. Sounds mad but I found that after running some ninjaflex with had to be oiled, when I switched back to pla there was dramatic improvement in flow. If I need to speed up a print for some reason I add some fellows performance shredder oil and crank up the temp.

My um2 has started misbehaving today. First I noticed that after pausing mid print I couldn't resume. That was 3 hours of filament in the bin :( Thought it was a no off so turned off at the mains for 30 sec but still won't resume after pause. I then noticed that during the change filament operation it wouldn't retract after reaching temp. I did notice that drive for the feeder had an ever so slight ticking motion ticking motion. I released the pressure (using Roberts feeder design) thinking something was jammed but even with the drive free still ticking. Issues seem to have started after ether using the pause at z plug in or simplify3d's stop a z hight option. It prints fine though,any ideas?

I did think of doing one for the existing 16mm bearing but like you say Robert the guild would have been to thin. You could make it thicker but thought it would interfere with the clip on piece that brings the feed hole closer to the drive wheel. But the 13mm is reasonably cheap so it shouldn't break the bank. I have thought about making one out of ninjaflex as it does seem to be pretty strong but was worried about layer separation over time.

Not sure if this has been done previously but thought I'd share a small improvement I've made to the feeder by IRobertI. I was having issues with NinjaFlex slipping off the bearing in the feeder. I decided that if the bearing surface had a u groove all my problems would be solved. Couldn't source a u groove bearing easily (although the wire guilds used in a wire straighter should work if you can find them at 16mm) so ordered some 13mm bearings from RS Components and printed some profiles to press fit over them. https://www.youmagine.com/designs/feeder-bearing-mod-for-flexible-filament Works with standard filament to so no need to switch out the bearing. See what you think. Again this may have been done already so apologies if so.