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Collecting and discussing themes for our magazine.
Re: Blowers v. fans for cooling PLA - 11 years ago
In early trials with air directed close to the nozzle I discovered the effect that LoboCNC mentions - there is actually not much cooling where you want it and there can be parts that get no cooling at all. A later design used an air ring which sent air directly down onto the print and was much more succesfull. I would have to admit though that it is only about the same as any good fan. I have attby leadinglights - General
Re: Abs temps - 11 years ago
That is the same reason that I was looking for low warp ABS in the printing forum - I have heard of a few that may fit the bill, the first two claim to be low warp ABS and I have ordered some ABS+ from Trideus. I hear that proto-pasta are trialing another high temperature version of PLA as even the one can't be used to make a glasses case that can be left on the dashboard under the Arizonaby leadinglights - General
Re: Abs temps - 11 years ago
The best temperature varies with many things: The obvious one is the ABS composition including the colourants used in it - the manufacturers may have added carbon black to remainders of other colours to make black for example. I had been happy with 236 hot end, 100 bed and no cooling but found that a design with crossed holes in close proximity caused delamination in the body of the print. Betteby leadinglights - General
Re: Does Bowden provide sufficient control for good prints? - 11 years ago
The more flexible the filament the less suitable it is, so things like Ninjaflex should be avoided. More retraction is needed with a Bowden so the print time is also increased trivially. Other than those, a Bowden setup can be pretty close to perfection.by leadinglights - General
Re: Is there any low warp ABS available in U.K. - 11 years ago
Yesterday I tried printing another batch of the same part, but using a freshly opened white ABS from 3D Filaprint. While greatly improved, there was still delamination. Today I went back to the TCT exhibitiobn at the Birmingham NEC to see if I could get any further input from filament suppliers there and had several useful suggestions. While I was at the Reprap stand, somebody that I was talkingby leadinglights - Printing
Re: What Infill percentage for strong parts (e.g. Guidler)? - 11 years ago
Where I have had similar problems the cause has most commonly been poor interlayer adhesion. This can be faulty filament or incorrectly set up temperature or flow rate. Try doing a calibration with that material and perhaps a test piece that you can do a purely subjective "rip it apart with a couple of pairs of pliers to see if it feels puny" test.by leadinglights - Printing
Re: Is there any low warp ABS available in U.K. - 11 years ago
I spoke to a number of knowledgable people at the TCT exhibition at the NEC yesterday and showed them the sample (photo in earlier mailing) and there seems to be a bit of a consensus as to the cause of this delamination when all normal causes had been eliminated: The ABS that I used was possibly substandard Black is not a good choice for mechanically stressed parts as undispersed carbon black cby leadinglights - Printing
Re: I actually need help and you all keep deleting my posts - 11 years ago
I fear that it has been a couple of years since I last used a Generation 6, but it still comes back as a nightmare*. The first thing was that it didn't have a bootloader - a small piece of software on the Atmel chip that allows actual running software like Marlin or Repetier firmware to run. In order to program this you needed a programmer; athough these are cheap and readily available, each oneby leadinglights - General
Re: I actually need help and you all keep deleting my posts - 11 years ago
Although I built a couple of Generation 6 boards for my first printers and even quite liked them, I think you would be better served by getting a RAMPS and Arduino Mega. The reason for this is that it is a nightmare suitable only for those with a knowledge and programmer for programming Atmel microcontrollers. When you have got it working, it still has no control for the bed heating. Mikeby leadinglights - General
Re: After 1 year Prusa i3: which printer now? - 11 years ago
Firstly, and my opinion only. It is counterproductive to do the old "what is the best printer technology" dance again - it is a bit like saying What is the best vehicle, bicycle or Boing 747". For myself, I think that there is a lot of mileage in FFF. I am trying to build a printer for multi materials with mountable heads. Imagine something that could print a tough material like Polycarbonate wiby leadinglights - General
Re: Is there any low warp ABS available in U.K. - 11 years ago
I have managed to take a picture of this problem to better explain. The photo is the worst of 8 prints, others wouldn't have photographed so well, but will still be too weak The print in question is an extruder. The smallest hole is the 2mm filament hole, mid size are for 3mm screws and largest hold is for a 6mm brass bar that the screws screw into. I think you will instantly see why this partby leadinglights - Printing
Re: Is there any low warp ABS available in U.K. - 11 years ago
Protected against drafts by enclosing the whole thing in a box made of large cell double wall bubble film. The temperature self limits to about 40 degrees. I know that geting the temperature up to 60 degrees on my Rostock makes for briliant prints but the Rostock does not achieve the accuracy of my Prusa 1 and the Prusa has PLA parts so even 40 degrees is a bit of a stretch. The best bet remainsby leadinglights - Printing
Re: Is there any low warp ABS available in U.K. - 11 years ago
I am having no problems with attachment to the bed (although it has taken me a long time to learn how to do that for most models) It is failure in the model, typically above 20 mm above the first layer. The only ways that I can think of to cure this are higher chamber temperature or ABS (or other high temperature material) with better anti-warp characteristics. The main types of this, SmartABS anby leadinglights - Printing
Is there any low warp ABS available in U.K. - 11 years ago
As above. I have managed to get ABS prints as flat and as dimensionally accurate as I need, but once I get excelent bed adhesion the shrinkage is relieved by delamination. Although this delamination is slight, it is in areas where there will be stress so is not acceptable. I believe that just a small improvement in warpage of the material will fix this, but am unable to find any suppliers in theby leadinglights - Printing
Re: New XY table printer - software question - 11 years ago
O.K., perhaps having pretty pictures does not get anybody interested, perhaps if I definded a little more clearly where I am having problems with the software side, somebody may have some helpful tips or even pointers as to where to look. So, in detail: The first need is to have some output from a RAMPS board on SPI, I2C or even RS232 when a tool change is requested. The question is how to do thby leadinglights - Reprappers
Re: New XY table printer - software question - 11 years ago
In case this is of interest to anybody- and also in the hope that somebody knowledgable in the software can advise me. I have started printing the parts for my 5 filament extruder but am held up for some parts for a couple of weeks. To further clarify the design, I have included some drawings and renderings. Showing two geared extruders and 3 bowden hot ends. The idea is to move the required hotby leadinglights - Reprappers
Re: Atfer Hbot, go to CoreXY. - 11 years ago
I was lurking through this thread and noticed the August16 posting from dougal1957 where one photo shows a carriage made from a plate with a comment "Think I may have to re-think the Y carriages as they take up to much room". Possibly these may be of help to him and anybody else that finds the idea helpful. The square cutouts, in this case in 2mm hard aluminium, have chamfers for the LM8UU beby leadinglights - CoreXY Machines
Re: New XY table printer - software question - 11 years ago
Hi cat.farmer The main point of lifting it to avoid raking the unused hot ends across the print. It also allows things like bed leveling probes to be part of the weaponry The design is coming along very sweetly at the moment, things keep simplifying themselves and I am hoping to put together a proof of principle in the next week or so. The loading door and locking bar works well as long as youby leadinglights - Reprappers
Re: New XY table printer - software question - 11 years ago
The turret would be constrained to about one full rotation. Any more than that and the filaments would get in a terrible tangle. for example, extruder 1 could be swapped out and replaced by extruder 4 by going clockwise, but if extruder 4 were to be replaced by extruder 1 then the turret would have to rotate counderclockwise. Direct wiring would be possible here. Having said that, I am now muchby leadinglights - Reprappers
Re: New XY table printer - software question - 11 years ago
Each hotend would have it's own temperature controller except the one selected for the first layer so that temperature for thet could be higher for the first layers.by leadinglights - Reprappers
Re: New XY table printer - software question - 11 years ago
The reason for the direct drive is that softer materials such as Ninjaflex do not work too well with a Bowden setup. Since I hear that even softer materials (including a very soft Silicone analogue) are being trialed it seems to be a good idea to use a close coupled setup (I will call it close coupled to avoid confusion with ungeared extruders) Your point about Bowden cables is well taken thoughby leadinglights - Reprappers
Re: New XY table printer - software question - 11 years ago
If the extruders are laid next to each other like a mouth organ instead of a turret then many of the problems go away. The extruder with it's gear could still be lowered onto the driving gear, with a number of extruders driven by a single stepper motor. Using software to position the gears such that they are already in mesh when the extruder gear is moved onto the motor gear etc.. Advantages ofby leadinglights - Reprappers
Re: New XY table printer - software question - 11 years ago
Hi cat.farmer, That is a good idea. I initially dismissed it as I thought there would be problems if the gear teeth were not aligned when the bevel gears were brought together. However, after a bit of thought I decided that this is a good case for fixing in software by the following sequence 1) When an extruder is about to be swapped out the filament is retracted by the required amount PLUS a liby leadinglights - Reprappers
Re: Is there an advantage to using IR to heat bed? - 11 years ago
I like the idea of using an IR heater for your bed, but two immediate probelms come to mind: 1) Does this constitute a fire risk? 2) Is the IR heater fixed while the bed moves towards/away from it. If so, the controll may be problematic. If the heater moves with the bed then there is a significant mass penalty when the hot end lifts (bed lowers) which it may do when crossing perimeters eby leadinglights - Reprappers
Re: New XY table printer - software question - 11 years ago
That was my original thought but I went away from that when I realised that lifting the hot end off of the print to move or to switch hot ends takes a significant time already. Doing this with a turret of 5 weighing up to 2kg would be pretty slow.. It would be better to have an additional motor to lift only the extruder/hot end that is at the datum position. (or even just the business end - but tby leadinglights - Reprappers
New XY table printer - software question - 11 years ago
I am building a new 3D printer and am hoping to short circuit some of the work on the software by picking the brains of the community. The whole philosophy of the new printer is to have an awful lot of extruders --- like this Initially I am hoping to have at least 5 extruder/hot ends and one other device - such as a bed leveling probe. since many extruders would result in great mass I have optby leadinglights - Reprappers
UK TCT Show + Personalize 2014? - 11 years ago
Is there any info on what is happening about the RepRap Hub at the above show at the NEC in September? I enormously enjoyed the 2013 show where I met many of the true heros of the RepRap community having read about it in: . If I manage to get my act together I may be able to finish my latest printer in time for this show and would like to know who to approach as I think that it may be of interby leadinglights - RepRap magazine