jameshs

PS - this is the way I change a nozzle. James

jimbojoe, I uses the Iroberti filter https://www.youmagine.com/designs/dust-filter%20and%20I%20find%20it%20really%20makes%20a%20difference%20-%20printing%20was%20straightforward,%20and%20on%20some%20filaments%20where%20I%20need%20oil%20I%20can%20lightly%20coat%20the%20sponge. For a sort of clean I do atomic in the printer. For a serious clean the easiest way i have found to clean is to take the nozzle off (when it is warm) and use a heat gun - holding in tweezers - over a board to let the PLA drip out. Then I use atomic on it with some filament - i.e. push it in and let it cool a bit and pull it out - as i can see the filament come through the extruder and see the shape of the inner nozzle on the filament I know I have cleared the nozzle. I still do this a few times. To clear the nozzle for really bad blockages I bought some hyperdermic needles - small and strong - and smaller than .4 - I warm the nozzle and then push the needle in and out - then do atomic. If I want to drill, then I drill a hole in some MDF wood, screw the nozzle firmly into that (so I know it is at 90) and then put a pin vice in my pillar drill (just a domestic drill in a stand) and hold the drill bit in that ... and gently use it. But I have never had to do this to clear a nozzle - just to make it bigger (I love a 0.65 nozzle) When I get under extrusion, it is either a bad filament (I have had 3 rolls that have 'become bad' from good suppliers) or the blockage - if a nozzle blocks once a month I think that the filament is bad. or the nozzle has just got dusty. the other thing to check - is that the hobbed bolt is clean. Open the extruder and either brush with a wire brush, or i use an air jet to clean out any ground filament. Check your delrin bearing (the round one that pushes the filament against the hobbed bolt - on one of my printers this did not move and was worn down - adding friction - I replaced it with a new bearing and that has really improved things. if you find this to be the case let em know and I will send you the ref for the bearing. (this new bearing also lets me print ninjaflex). Check the tension on your extruder spring - neither too hard or too soft! Any one of those can cause under extrusion. Hope that helps! James

I regularly swap out nozzles on the UM1 to clean them and to swap nozzle diameters - frankly I am amazed at what they can do when squeezing plastic through a 0.4mm hole! - I put a dust cleaner on my filament and some old filaments just clog - and I throw them away, but that is rare. When I look at the number of moving parts, the number of user variables I am continuously amazed at the reliability of these machines (I have 2 UM1s). Just changing the filament - from the same manufacturer - causes changes in the settings to get a good print, and IMO you just need to get a feel for it or stick to a single filament type. I am always popping my bowden in and out - if it pops out on its own you may not have the tensioner in the bowden holder - or print up one from T.V. I lightly oil my machine, wipe it down a bit, tighten the screws and away they go - normally the two of them printing my own stuff and commercial (3dhub) orders or e-nable hands. Some days they need a bit more maintenance than others, but most days they are plug and play (after a few tweaks to get the settings right. From what I have seen the UM2 is a move towards more P&P but inevitably has some of the issues from 3dp process - and not being able to change the nozzle is one that stops me from upgrading (apart from being able to justify three printers!) However, from my reading of the other fora (see mb Gen 5) I think they have achieved a good balance of price point reliability and availability. There are other machines like the Zortrax but they force you to print always on rafts, or the Lulzbot - but you are again a hands on tinkerer. Most days I have to help my inkjet and laser printers with paper jams or door switches - and would put my UM up there - but it DOES need more operator input I agree. James

on an unheated UMO I just went to my glass shop and had two sheets of 'picture glass (3mm) cut and edges polished for £3 ..... has worked for nearly a year and allows me to swap them out (well it did until I got my second UMO )

even between spools (over months) it can be different - you just need to get to know each filament - some string more than others. I generally print colorfabb pla/pha at 215 for the first layer to bond to glass, and 208 for a fairly fast print with few cross movements and 204 for something slower where stringing might be an issue. - but some of the clear colours need a higher temp - add 10 degrees. colour change I have never seen - unless it is old filament in the nozzle - but that would run out fairly soon. filament does age too - I find year old filament is much fussier and breaks if I leave it in the printer overnight - so I have tried to come up with things to print with these rolls that are 'disposable )

which has saved me on more than one occasion when I put a glass bed on but forgot to put a 3mm extension on my end stop .... love that flexibility

Sorry - yes S3D is simplify. I jumped in as I wanted spiralise but also to fill the top - and s3d does that - the fairphone case with africa on the front showed the scar and I just could not get rid of it - but I could in s3d. Since then I have appreciated the control of different features at different height - and the fast that I can manually position support - and boy does the support come off easily! But it paid for itself quickly with the fairphone cases as printing time dropped to about 2 hours and less failures - I started to think it was earning me money, but then hit a few buggy stls and a few breakages - the whole thing amazes me - the quality of the print and the case design really stretched what I though was possible - but change filament colour and the layer bonding changes subtly needing 2 degrees more print temp etc and I hand finished each one with wet and dry paper - but only after bending them in a kind of torture test to delaminate them Fun! - oh, and everybody ordered ORANGE - I kept having to re-order!

Simple test - when you are ready to extrude (at the correct nozzle temp) and you turn the extruder cog by hand do you get a noodle? - I always hand prime while the UM is heating up so I have fresh well flowing PLA PLA will stick to cold glass with PVA glue on it - it is my favourite printing platform, so a warm one will be even more yummy!

Using S3D definitely helped in my fairfone case days (I de-badged after 12 as there were a few models that had 'errors' in them that I had to edit in meshmixer and then hand edit the gcode to get them to print ..... which still caused some layer delaminaton and repeat prints so as not to disappoint customers - so I decided it was a great venture but not quite mature enough compared to the stress James

How big is the piece - looks small? - if it is small then it is several things - stringing, plus the fact that the nozzle is too hot and re-melting - difficult to avoid with a piece that small - I was asked to print a cog with similar teeth and it just melted them on each pass - just like that and that is the limitatation of the printer on weeney small pieces. I would try printing it on its side as you won't have that problem. If that works then you could break the model in 2 and print and join (just sink it into the printbed by 50% of the height.) or use support - but I think support might be worse. You could also try printing it upside down. Or re-design so that the teeth have a flat top - often you don't have any contact on that top part - so more like a pinon. James

try spiralise - which will let you know if it is a random zscar.

I found a happy compromise at 0.65mm for architectural models and ninjaflex I just screwed the nozzle into a piece of MDF and put a pin vice with a .65mm drill in my pillar drill (diy drill diy pillar) and it just worked - I drilled from the top. Might have been beginner's luck ..... oh, I had 5 spare nozzles just in case and some spare drills! Cuts some prints from 12 hours to 4 or less as I do a single pass wall - these are architecture 'makettes' that take up the whole build plate. I do tend to break up the models though to get the best print orientation and then assemble them - so the glass is used for a really good wall face. Have a go - it was a 3 minute operation! Works great for ninjaflex with a slight feeder mod. PS - this was UM1 - you don't say which one you want to mod. James

I don't know of any where they have done the work for you ..... if I see something useful I just buy a sample and try it - if I like it (or can get it to work ....) What are your customers asking for? As an example I have been printing e-nable hands - a small part in PLA which tensions the cable just snaps ..... so I got out a sample of the new colorfabb Xt and it is SO strong - I can't break it - but it took a bit of experimenting (240 degrees and no fan - which seems wrong ) I know the samples/time trying are expensive, but I normally pull them out when I am driven to by my favourite filament not working! Some good reviews on flexible filaments on here - I love ninjaflex but it is a PITA to print James

polishing your head on youtube - this I have to see - eeeeuuugh! James

As far as I am aware it would be area .... otherwise it is like you said!

I noticed that the other day when I adjusted it on the controller - but this was a random thing in different places on the print - it would skip a whole line and then carry on like normal with just the infill holding it together! - back to 100% and everything was fine. If you get to the bottom of it I would love to know!

Worth looking at user error before the software! That is what often happens when the z stage moves - look at changing several parameters (always worth doing this one at a time) Print at the lowest temp possible Print as slow as possible Check your flow and filament are dialled in Adjust your z change speed to be higher you should be able to eradicate most of this artefact.

exactly - the opposite - if you want more flow you tell it the filament is smaller as cura then thinks it has to push more mm thought to achieve the volume - as the filament is bigger than cura knows it pushes through more plastic. so to get 110 flow when the flow is on 100% then decrease the filament diameter by the area/1.10 turned into the diameter.

Hi Sander - as far as I know Barnacules has a roboPRINTER not a ROBOX - very different machines! James

I am another UMO owner and have just bought the heatbed upgrade - fantastic printer (I have 2 ) but I don't think it would be great for an apartment - they are noisy ..... as a printer I like the noise, but when I have it at home I move it around the house depending on whether people are sleeping or watching TV etc - you cannot sit in the same room. And bear in mind that most prints are in the multiple hours (6-12) Dual extrusion with supports - I have not yet seen this successfully achieved - in fact I do not see many people yet using dual - and personally only have one desire - to mix solid and rubber, but I have only seen the lulzbot do this successfully. If you dropped that from your wish list the UM2 would be the only answer - UM+ has to mod to do dual and heatbed - so you have dual, no heatbed on the UMO, heatbed and single on the UM+ or heatbed and single on the UM2 - or mod the UM+ with PS for dual, or Mod the UMO dual with an external heatbed - I want everything and I would do none of these I thought of my wish list and after a year of pushing my UMO's am still discovering what PLA can do (though I do use XT a lot) have just started playing with ninjaflex (on a UMO) but love being able to drill out nozzles (I have 8) and am about to upgrade one of them to heatbed (for XT) James

They have produced some really interesting multi-tools in the past - they are heavy end industrial designers so may have over thought some of the things - time to see what works and absorb!

I do hand work with wet and dry (wet it!) - the dremel was just heating the plastic (PLA)

It is a full time discount (I asked 3dh at TCT show yesterday) - no idea how it is done but the highest discount is 30%! - My guess is that is volume driven, but also sounds like it is variable - and may soon be linked to your order history. Anyway - any discount is going to be good!

So far hot end lasts ....... ages If I get prime moving like that I wipe the hot end (careful, it is hot!) with some tissue to clean off the gunk - that normally fixes it. Then rarely I do atomc, then even rarer I change out the nozzle for a clean (heat plus needle)!

no orders yet - but it was fun to do the sample (the gears) and fine tune to get it to work! James