jameshs

Warm it up, not too hot, push it out. Coathanger, or other filament (xt or abs) not pla It is what is called a plug.

that was probably a cool zone blockage. switch off ..... if you can't get the bowden out (sometimes it needs a bit of encouragement while you are pressing down with needle nozed pliers) then don't be afraid of taking the whole hot end apart so that you can then (switch on) warm up the heater and (switch off) push from below to release the blockage - only to about 140 and then I use a piece of cut coat hanger (gentle not to scratch anything) - that should set you back right. 30 minutes max

Understood - I have two UMOs and print all my PLA and some XT on cold glass - I have a taped up platform under for when XT won't play ball (sometimes warming the glass with a hair dryer stops warping) and a small piece that changes the end-stop to allow for the glass - so no changes to the machine and the parts pop off. It can even be used for ninjaflex! (yes slooooow printing). I tried lexan and a few other plastics but glass is so good. Just glass and PVA glue on a UM1 - I have bought the UMO+ upgrade but not yet put it on. James

No guide sorry new bearing in feeder. regular tightening of nuts regular cleaning of print area regular clearing out of nozzles and filament path regular oiling of all rods and bushes regular check of level seating on the bench regular checking of filament and temp profiles yearly take apart the hot end assembly and check everything is ok periodic checking the cables are all well-seated periodic tightening motor mount belts etc periodic print calibration pieces periodic taking apart the feeder - recently repaired some fo the flaking off bits of ply with 2 part epoxy and feed went much better. let me know if there is anything I am missing! James

dislike the idea of badges, and dislike the idea of rating - in the same way s I HATE the FB decision to show me 'top stories' in my timeline rather than 'most recent'. It is my timeline! I read the messages I want tor read and actually I think I am able to work out which ones are useful - and in fact I like to read all the answers/messages as they always throw some light on the subject even if the answer is wacky! I DO understand that you want to improve what is probably already the best community forum - so this is not an argument for stasis, but 'badges' IMHO is not the way to do it (I would see it as dumbing down and be really sad :() You already have a forum that makes me visit twice a day, with the best 'since last visit' function of ANY that I visit. Discounts are always fun - but we are already fully engaged and a once off would be a bit strange (I get a regular one from my 3dhubs membership - which varies by how much I print - so a completely understandable relationship). I love the variety of the discussion on here and anything changing how I 'see' them would upset me Put a poll up (hate them too) and then obey the numbers ! James

The first solution has to be to get rid of the tape have you tried cold glass with PLA?

I think that the article is a good start - there is no harm in studies which assess the safety of any particular process and we are melting plastics, often in the home environment. Every plastic produces a 'smell' which means that you are sensing something and breathing it in. Currently I don't feel that 3dp is exposing me to anything more than when I un-cap a sharpie or drink from a polystyrene cup or use clingfilm - but I do limit my exposure to those things and I do limit my exposure to the potential effects of 3dp by operating them in a reasonably well ventilated space. Photocopiers went through the same scrutiny and developed integrated filters which considerably reduced their outputs (and I can still smell when they are working) so this is not an unusual part of an office environment product going through growing pains. Keep an eye on the outcome and form a well reasoned opinion - just because high cooking temp by-products are also bad for you is not a reason to not listen to this research - but how you react may be tempered by your perceived risk of exposure. Would I put these in a bedroom in which I slept - no. Would I currently use them in a well ventilated normal room - yes I would (based on my current understanding of the risk). If I were building a commercial space where they placed a large number of these I would definitely ventilate the space to a commercial standard.

Also wires on the top of the print-head - I unscrewed the holder of the 'blue' led and pushed the leads in and then re-tightened. Intermittent as the head moves around. James

some filament is duff - check other filament types. For tightness I open it up all the way, and then tighen it until I can't pull it out with light finger pressure - i.e. not very tight at all. If temp is good, nozzle clear then it does not take much push to get everything to work. I have some filament that was good but now prints for about 3 hours before it cloggs, reduces flow and goes fluffy. I know it is the filament because I have cleaned, put it back in repeat - same thing, whereas when I clean, put in different filament - all good for 12 hours + It seems on year old filament this can happen - so now I prototype in old filament and keep my stocks lower. End up with some fun prototypes

side clips to hold draft panels and a wedge to hold in the extruder to the back wall - that is it! - everything else just seems to work Oh - and iRoberti's dust filter - amazed how dirty the sponge gets. I have 2 umos and they are working hard for the last 12 months on items as small as earrings and large as architectural models - they just seem bulletproof (I do regular maintenance, tightening, and oiling.)

Initial layer thickness overrides your layer height thickness for the first layer - say your layer height thickness is 0.1 but your initial layer thickness is 0.3 then the base layer is put down with a bit more splodge to get it to stick well. Bottom layer thickness and top layer thickness are the number of layers put down before you get to your 'fill' variable - and this is important. Let's say you use 10% infill - it is obvious with your .1 layer height there would barely be any material covering over the top of your infill matrix. So if you want 10 layers at the bottom of your part - then with the .3 setting it will put a first layer of your bottom layer down a bit thicker to hold the part, and then complete the 7 other layers to give you 1mm (I think that it right and that the base layer would not be 1.2mm but don't know that for sure.) Hope that is clearer

To avoid that I run the nozzle to temp, once near temp I manually prime the wheel, as it travels to 0,0 I hold the filament noodle with tweezers - so it hits the glass clean - using S3D it then sets off and primes and I just pull the noodle/thread away so that when it hit for the print there is no gunk and it is fully primed ready to go. (But I don't use skirts which is part of the priming process in Cura). Maybe I am too anal!

Ah, Understood - I am there with tweezers after a hand prime - no mess James

I don't have the corner cut off and once forgot to put my little end-stop fooler in and on my 3mm thick picture glass (cheapest they had) the bed spring just took up the plate - no breakage! maybe I was just lucky! James

Dump the blue tape and print on glass Even XT I print on glass (except for some really long prints) I have the blue tape sitting under the glass in case I need it and just remove a small 3mm (glass depth) piece from the end stop. If I have tricky print or it is cold I pre-heat the glass with a hair dryer for a while to get the whole machine 'warm'. I rarely print on blue tape now. UMO - no HB (waiting to install kit but in no hurry )

I think there are .25 Bear in mind that the nozzle hovering over the layer below can re-melt it - so there is a trade off with speed and heat! IMO 4 up would make no difference over 2 up Using something like XT can help as this is slightly more resistant to the re-heating - so some things I can't do in PLA I can do in XT James

personally I find a lower print speed more layers and maybe try with NO infill I find that the infill sometimes interferes with that nice round movement and jerks off and then over sails a bit. Plus check all the usual culprits like well lubricated rods, tight belts & pulleys. firmly sitting on its base etc. But I think sloooower is probably one of the biggest helps. James

interesting discussion. i am prototyping the arm as we speak and over the last 2 days have been working with XT and PLA (both colorfabb) and while XT 'feels' stronger - it is still more difficult to print with. I print on a cold HB with glass and pla glue. XT 'can' stick to this but you need to go slooooow and hot with no fan - and some of the bridging with that setup can be poor. Whereas PLA just prints! So I have switched back to PLA which is SO easy to print with and amply strong enough at the moment. The only thing i use XT for definitely is the tensioners - they kind of crumble in PLA whereas in XT they have proved unbreakable (better layer adhesion and resist heating when I drill them out for the screws.

Hi Didier - answers in your post ....

Have to say - some colorfabb filaments do just fail after a few hours. I exclusively use their filament and have probably three rolls of different colours (black, white and pink) that I think are just 'old' or different. The other test for me is that if I leave them overnight in the printer then next morning the bend will be broken (snapped). So I just use them for small sizing prototypes where the print is no longer than an hour and I don't need the strength. - I do have the same colours that DO work so I think it is a batch/age thing and now I try to keep smaller quantities 'in stock' - but the same colour in a different reel 'just prints' - and XT just prints beautifully - but does need special care on a non hb glass

Hi Didier, It is a worldwide thing and you just 'volunteer'! Ideally you will have printed out a test hand so that you go through the 'growing pains' and work out how all the scaling stuff works. Then you fill in a matching form to show where you are ans what you want to help with - and then a matching service will put you in touch with a recipient. The recipient will have submitted a set of photographs and measurements that help you to get the scale and size right and which hand they would prefer and you take it from there. How you customise (colours etc) are between you and the recipient - depends on the age, bu the two I have done so far wanted Spiderman superhero, and 'rainbow. If you have modelling skills and are not happy with the 'product' then t is open source and the community welcomes input back into the designs. Some designs need more 'vitamines' than others - both of mine have been for RIT Arms (a cuff above the elbow as the recipient has no wrist) and that design is 'evolving'. I have been playing with ways to get info on exact measurements in case anyone wants I will go through more - it involves making ghost hands in selotape I was really surprised that I was providing hands for children in the UK - we have a good health system! - but they are children who are just not getting appropriate things from the NHS. These are semi-functional products with faults and benefits - but the psychological boost is large for the children who have been provided so far. Do not understimate the complication of actually printing and assembling - and the designs are not currently 'easy' to print - you are looking at a good 20-30 hours of input to your first hand, and getting all the vitamines, but after that it becomes 'easier' A project fully supported by UM too! (They have donated some printers in the US.) Hope that helps! James

I think e-bay is a bit of a buy what is seen if he accepted that you had done a 15 minute test then that is his risk - yu showed that it was working to that test when it left your hands. Plus those parts are NOT that expensive. I once bought something that had been advertised as working ans clearly was not when I got it - the seller paid for the spare parts which I replaced - you could go that route, or just tell him that it was working when it left you. He took it apart rather than come back to you and say it was not working ...... IMHO James

In London I had 2 pieces of picture glass cut and ground for £3 - the edge grinding is normal. I guess a quick chat with the grinding guy would easily round them if needed (mine was for a UM1) or go back to clips (just while you wait) Mine is not on a hb so I would heat them up slowly, and possibly not use the fridge - though you don't hear much about cracking. (get 2 ) James

Z axis tighten belt tension check pulleys are tight check belts running in pulleys light sewing machine oil or wd40 wiped on to ease old crud

I find if i heat the head first, soft grip wit square nozed pliers and then a 10mm spanner carefully when it is hot .... So far not even a mark. I use colorfabb filaments ... But the do age. Atomic is same on every machine. Needles from ebay ... Where else!