Artiz

So how many carbon filaments have you tried... was thinking of trying out this 3DXMAX® CARBON FIBER PETG FILAMENT but not sure the extra expense is worth it...

great post though thanks for the info...

Not very 'Ninja Style' neotko...

wicked post danilius... much thanks for the info... being mostly interested in carbon I'm wondering now if the carbon/PETG mix from 3DXMAX is worth a trial. I have found with XT-CF20 that it can be a bit 'flaky' on the finer edges of my parts when sanding down. Although a coat of cellulose spray sealer does seem to cure that problem. Have you finely measured post print for shrinkage danilius?

PETG seems to be another alternative regarding strength and accuracy (low shrinkage)?

I've certainly been interested in the 3DXMAX® CARBON FIBER PETG FILAMENT but there seems to be very little info about PETG itself... can you tell us any more danilius

Yes definitely... I used a cellulose sealer on MK1 which is not only waterproof but also scratch resistant-ish... a bit expensive but it also looks lush so definitely worth it. I left a piece of printed XT-CF20 in salt water for a few days as a test with no adverse result so I'm surprised you found different?

ah yes my obsession... going very well thanks... update here

Always loved the concept of 3D printing but until last year also knew/thought it was too early in the technologies evolution to produce solid and accurate working parts that also had some kind of durability attached... although with the ability to just keep on producing exactly the same part perhaps durability is not so important anyway. Most reasonably priced basic spearguns are usually Delrin (DuPont) or a Polyoxymethylene derivative used in injection molded manufacturing... real high performance plastic. So... could I 3D print a speargun which might compare even at the most basic performance levels... well I thought I'd give it a try. Initial testing with PLA and ABS were encouraging but hardly successful... accuracy/shrinking/warping of prints was continual and hardly a new problem which seemed to doom my ambitious project to abject failure. Then carbon filament arrived... MK1 was a small and successfully tested speargun at the end of last year which hasn't yet caught any fish but that's besides the point... it was used 3 times and is still intact and has proved to be an extremely useful prototype. MK2 is being printed right now... To say I'm pleased so far halfway through the printing stage is an understatement... but the real 'working part' tests are still clearly yet to come! all handle parts have been printed with ColorFabb's XT-CF20 at various settings

A few irritating issues with the handle regarding the support structure and general adhesion which looked disastrous initially but I managed to save it... at 15 hours in... it was not a pleasant experience. I've got a large ridge a third of the way up but layer adhesion looks OK.

I can certainly see why this is not one of your favourite materials Labern... I eventually managed to get it to print where the layers would 'meld' together and within an hour it had just come completely unstuck from the buildplate... very disappointing material... being XT I thought this was the same co-polymer in XT-CF20 but it certainly prints very differently and very much better with the addition of carbon if it is.

Going well so far... bit more post-print work than I'd hoped for though... the speargun body was printed @ 0.6 LH, 50% infill and 3mm wall and took 24 hrs for both sides together. The handle is going to take 36 hours... gulp! I need to screw into it and it obviously needs to be as strong as I can make it so I've opted for .8 LH, 75% infill and a 5mm wall... at 0.6 LH plus 100% infill it would've taken 100 hours! P.S. I've just bought more of this filament direct from ColorFabb who seem to be the only ones who have it in stock at the moment. A 2.2kg reel was £102. delivered to the UK... looks like they're the cheapest too.

Doh... I ordered a reel of this by mistake and got it today. I managed to start printing with it quite quickly after reading your advice here so thanks to all. The most important factor is to it slow right down to get it started/stick... I use a cellulose sealer spray for most of my printing and it seems to work for this too. What I'm still unsure of is what is its purpose or use? Is it just a general type of filament or does it have properties which have passed me by... its very shiny but my small finished test prints are quite brittle so the strength selling point seems moot. Any ideas anyone?

ColorFabb's XT-CF20 doesn't shrink at all... might even expand a little if my latest print is anything to go by... thanks for the info here... everything makes a bit more sense now...

Footnote: I tried printing XT-CF20 without retraction for the first time today and I have to report I think its more trouble than its worth... all the tails & mess it creates seems to continually jeopardize the actual print... and at 24 hours and still counting I haven't been able to leave it alone without 'Ninja Style' fiddling as neotko so appropriately calls it (new thread there called 'Ninja 3D Printing Technique's by neotko - please!)... I have also had to pause and sand down large build ups which were making the hot end jump violently... turning retraction off is probably OK for small single prints but anything substantial and multiple part prints in particular I would definitely advise using retraction and then adjust material flow 'on the fly' to compensate. I do have to add that this particular print is the culmination of quite a few years work so I am probably over fussing too!

Your instructions are far more comprehensive so that should do it... thanks for posting up! P.S. That last bit of info is also very important from fbrc8-erin regarding the fan... I thought there may still be something wrong because the fan kept switching off/didn't come on etc... so good to know!

Good question.... thanks for asking it.

I've started printing my concept speargun at ulti settings now and the results are exceeding my expectations. I have done a bit of post-print work but for the results you get regarding strength and quality... and possibly durability... its looking so worth it. I can't believe how 'sturdy' it feels in my hand. Best filament so far... for working parts.

I couldn't help reading this post all the way through... absolutely fascinating, appalling and irksome all at the same time. I have to say that I do feel sorry for shamai_k... it is an elaborate scam GoGoshop (Israel) is running here. GoGoshop even posts up Github assembly instructions here which makes it look as if Ultimaker do indeed do a self assembly kit... ( OP's broken link here) I can only conclude that you were a bit hard on the OP cloakfiend... after the site is roughly translated I think I would probably have believed it to be a genuine Ultimaker product too and the lowlife is still selling it (I might even buy one cos I'm also a mug for a bargain )... I can only hope you/shamai_k got his money back and Ultimaker are doing everything in their power to help him out if he didn't/hasn't? Can you (shamai_k)/somebody/anybody let us know please so that nobody else gets 'mugged off' by this 'charlatan' or others like him. This is clearly the slippery downside of 'open source'!

I thought I would add this topic mainly because I couldn't find any tips or guidance regarding changing over the PCB on my still under warranty UM2 Ex.... and to say I was looking for HELP doesn't really cover my initial anxiety. I think it's safe to assume it's the same PCB for all UM2's but happy to be corrected... which goes for anything else I might get wrong here... My problems started with a Z switch error which escalated to a new mainboard replacement... supplied very quickly by Ultimaker (thanks very much). Being a newbie and not having any electrical/techy experience I was freaked out by replacing the Z switch let alone a main board switch over. DIY warranties are still a whole new concept to me. Anyway having been 'down' to the PCB before after replacing sensor/heat cartridge... like everyone else... taking the bottom cover off hardly needs describing... nor should removing the power cable. With the UM2 on it's side and the back left metal cable guard removed you can now remove the 4 allen screws which attach the board. Take care with the black spacers which can drop off (into oblivion) as you remove these screws. Might be a good idea to take your own photo now and also a good idea to have a particularly observant look at where everything goes. I placed the new board just above (on the side of the machine) so that I could then simply remove from the old and replace straight into the new... easy stuff! TIP... don't forget that the cables must be sitting behind or on the bottom of the board rather than trapped between the board and the bottom of the machine. It's therefore easier to replace the heat cartridge/sensor wires first (which can be a bit fiddly) before finally adding your stepper motor connectors. Lastly check all cables and connections making sure you have not damaged/broken anything. I then put one of the screws back in nearest to the switch before carefully standing the UM2 up, connected the power and switched on... having previously 'factory reset' I went through the initial set up procedures but not sure if this was the best idea... I just didn't want to put everything back together and then find a problem meaning I'd have to take it all apart again. I then turned off, removed power and replaced the board correctly. Finally I connected the USB and ran the latest Firmware again for good measure. P.S. I also fitted a new Olsson block at the same time but that's more than covered elsewhere... it did however cause some separate/puzzling printing issues which have now been resolved. Hope this helps...

I tried acetone too which didn't work at all for me... what I did find good about this material was the way it sanded down though... better than any other material I've used so far. Starting off rough to get a good surface and then working my way through only a couple of grades to a very fine 4-600 finish... looks great. I then sprayed it with a clear matt cellulose sealer... superb! The carbon fibres make for a really tough outer skin which seems to make the sanding process the best way to finish off prints. I used wet and dry sanding paper by the way.

It also took me a while to find your original advice/post which Jay-Cee quoted because it's called 'SLOW SUPPORT' and doesn't come to the top of forum searches regarding Z switch errors. Your advice there is indeed 'golden' as Jay-Cee said in his post. Messing around trying to work out if the switch is faulty manually is both frustrating and irritating to say the least. Having then replaced the switch and still having the error is even more depressing still. So yes I do now know that it's a circuit board failure but I could have got there a whole lot quicker... however, I wouldn't now have the foundations for my very own 3D printer farm after buying my second UM2 (used) for an extremely reasonable price... would I? Much thanks for your advice, help and kind comments here gr5... invaluable!

He got to the root cause by finding something that was already posted on the forum before, so in effect he did get help from the community, he just didn't get it "spoon fed" as it were. And I'm not sure how anyone would ever have been able to guess that he accidentally re-installed the same board again. Like gr5 said, I think people were really confused and didn't know what to say. A lot of people spend a LOT of their own time helping people here, I lost count on how many hours I've spent here over the years (I will freely admit I haven't spent as much time as I want/should the past few months though). It's a bit annoying when people complain about not getting help immediately when this is all done on a voluntary basis and often times the answer can be found by searching previous posts. Yes, it's frustrating when it takes a bit longer to get a reply but you have to remember that we're only human and sometimes we simply don't have a clear answer to give. Sorry about the rant... one of those days. 'spoon fed' is the crux here... This technology & forum should be about 'everyone' adding their 'bit' and my pointing out that he didn't get much help from the community was exactly that... 'everyone' not you, gr5 (or tinkergnome) in particular... you both (all) provide excellent advice so your 'rant' is indeed a rant and therefore disappointingly taken out of context as well as personally. For me we are all here to 'spoon feed' each other... why not? If it helps it helps... as long as we all continue to do it. I've heard that 'spoon feeding' nonsense elsewhere on forums and I find it irritating and superior... when you are a starter/beginner/newbie etc... you are indeed a baby and need a bit of spoon feeding/comfort/love... nothing wrong with that... besides it encourages you in your turn to continue 'spoon feeding' other starters thereby alleviating the burden from more experienced contributors. Some forum posters may even be children so we don't need barriers here just repeat or refer (link)... it takes seconds. respect & regards

For anyone else with this problem the goto> advice is download 'Pronterface' (GUI host of Printrun) as Jay-Cee did above and have a fiddle around. Printrun is a 'must have' regarding free, open source, 3D printing software... any time spent 'innit' will not be wasted... besides who wants to go out and buy a new multimeter/tester? The STOP error's regarding the Z switch in particular are not reliable or even specific on the UM2. It's probably a given to check for correct switch clicking/movement/position and/or blockage but also important to have a good look around and clean anyway. If error persists you can then try installing the latest firmware and/or factory reset too. Next step is Printrun which allows you to move any axis and discover whether they are indeed moveable... plus many other invaluable functions of course. If you can move it then change the switch... you don't need to remove the Z motor either to replace the Z switch by the way... just remove the bottom/back 4 screws and then use a flat head screw driver to slightly & carefully lever the back edge away from the Z motor so that you can remove and then replace the wires correctly down behind the Z motor. Not a bad idea to have a set of switches 'in stock' either. Repeat advice from gr5 (above)... "If it's not the switch and motor still does not move, swap the cables for the X and Z stepper motors. Try to move the Z axis by telling pronterface to move the X axis. If the Z axis now moves then the problem was with the Z driver. Explain this test to Ultimaker and ship the board back to them." Hope this helps...