Jump to content

zumfab

Dormant
  • Posts

    238
  • Joined

  • Last visited

Posts posted by zumfab

  1. Even 75 mm/s seems acceptable, as 50 mm/s is pretty much top speed for me. It is getting to the point where I wonder what parts of the Ultimaker will remain original after all the upgrades though :D Pretty much every part is getting updated or replaced.

    I never really considered noise a huge issue, but reducing it while improving other factors is a nice bonus.

     

  2. POM is great. But afaik you can't lasercut it (I may be wrong here?).

     

    I never did, but I think you can: http://www.eurolaser.com/materials/polyoxymethylene-pom/ But indeed, POM is not cheap at all, but it is a real structural material, whereas acrylic always seems a huge compromise. HPL seems a great material too, though unfortunately I cannot figure out a way of processing that without changing the design quite a bit. You really need to router that, rather than laser it.

    Looking at the different materials I felt that plain old steel has a lot going for it. Thermal stability is pretty good, especially compared to aluminum, and it's very strong and fairly cheap. You will need to protect it against rust and it is not the lightest, but as long as you do not try to make 6mm panels out of steel that will not be as bad as it sounds. The weight helps to reduce vibrations and noise too, often a problem with aluminum. Cutting is a bit harder though, you will need to pay someone to do that.

    The resulting printer is a rather different device than the Ultimaker we know, but you should end up with a very robust printer.

     

  3. Acrylic is a bit of a distaster from an engineering point of view. It is rather fragile and has some other drawbacks. If you want to go with plastics you might go with something that is a little more high grade, like POM, but unfortunately that also means things become rather expensive quickly.

    Mind you, I never did a full evaluation of POM, but it tends to be superior in most applications.

     

  4. Some hypodermic and acupuncture needles can be found smaller than .4mm. I ordered some online and they work well for this kind of thing.

     

    I second the acupuncture needles. They have worked for me, though you might need more than one. Use them on a heated hotend, obviously.

     

  5. The feeder on the UMO isn't direct drive and the stepper it uses isn't strong enough to be either, so it's not exactly a drop in replacement.

     

    I was thinking of making it into something like a hybrid. Retain the stepper and reduction gears since that seems to work pretty well, but take the rest of your design. It would need some sort of UMO compatible mounting system anyway, so doing that would not mean a lot of extra work.

    That is all under the assumption that it is actually a useful upgrade.

     

  6. But also, we (at ultimaker) got told not to print anything that looks like a firearm at the office. Just for press related reasons (Ultimaker prints guns! is just a bad headline)

     

    From a business perspective and all the bad hype around the printing of firearms or parts that is a very sensible decision. So much potential for a fun hobby project to become the centre of a publicity storm, it's best to just stay away from it completely. Let others deal with that, if at all.

    Though it is hard to understand why there is this widespread fear for 3D printed weapons. I don't think CNC machining ever had to deal with this kind of nonsense.

     

  7. Technical question, which is the most robust material that the Ultimaker 2 can reliably print with? Colorfab XT by any chance? I dont want to print in ABS as it warps terribly and clogged up my nozzle. This gun is printed completely in PLA by German Reprap, but I fear it might break if I ever go out and play with this gun and put it under stress.

    If you are going to mass produce (even if only small production runs) you might consider casting your guns, rather than printing them. Not only will that probably be easier after an initial investment, the result might also be of a higher quality.

    Though I do realise this might be the wrong forum to propose such a thing :D

     

  8. After finally dealing with and fixing not one but two separate problems that have plagued me for a while now, I decided it was time to waste some filament and print a frivolous 'long' print. I was not brave enough to do a 18 hour print, but this hour long one did nicely.

    It is 67P/Churyumov-Gerasimenko, printed from data supplied by ESA. Proper color and all. It might be one of the most elaborate ways of obtaining STL data :D The real print is actually quite a bit nicer than in the picture. The details are pretty good, despite its rather small size. It is not amazing and does not really compare to the other prints here, but it's decent enough.

    I might do a bigger one later on, when I have the settings dialled in a little more.

    gallery_36399_1711_274966.png

     

  9. Well, today I poked a hole through the hotend with a fine needle a couple of times, freeing up the flow. Atomic pulls still come up weird. Lowered the temperature, retried, still weird. I threw up my hands, put the hotend back together and attempted a print only to find out that everything prints fine now. I have not tested a lot yet, about 1,5 or 2 hours worth of printing, but so far so good.

    Not sure what to make of the weird pulls, but hey, if it works then I am not complaining. Added bonus is that bridging went from terrible to great :)

     

  10. Since those things are made of mostly the same part, it would probably be quicker and more efficient to mould the pieces. Make a 5-10 piece mold, cast one or two batches a day and you're golden.

    Advantage is that you could use some high quality engineering grade resin.

     

  11. I bought a SD card, so I should be testing shortly, as soon as I fix my clogged hotend. Since I was not sure whether SD or SDHC makes any difference I dug up a normal SD card. Those are becoming a bit rare. Does anyone know whether that makes a difference?

    Since I slightly damaged the cables I also bought material to make them myself, so now I can put the nubs on the right side. I didn't really mind the filed down nubs, as they fit quite snugly, but I do want the cables themselves undamaged.

     

  12. I am having this same issue right now, though the hotend went from slightly blocked, the reason to attempt a pull, to completely blocked :( I tried pulling at a cooler 80 degrees, but I still get the stringy pulls.

    I guess I will have to take the whole thing apart tomorrow. I have spares, though I would rather only use them if absolutely needed.

     

  13. I think you are overly concerned about the couplers. Couplers are very common in CNC systems.

     

    It depends on what you call concerned. I do not mind couplers in general, but in this case they add a lot of bulk to the whole set-up and put the motors in a vulnerable position when moving the printer around. I think they are not really needed anyway. That is why I would prefer to eliminate them, not because of some inherent dislike for couplers in general :) And if it does turn out to be the best solution to use them, I at least fiddled with it a bit and had some fun.

    That is probably more of a discussion for the direct drive thread though.

     

    Don't forget you will get rid of the variable 'short belts'...

     

    Fair enough.

    Edit: those cable tensioners work miracles. From sloppy prints with major issues to tight and smooth delight.

     

  14. Biodegradable or not, plastics tend to have a hard time outside anyway. If things have not been UV proofed in some way they will degrade fairly quickly. The sun is unforgiving in that respect.

    I put a couple of plastic containers that are intended for use inside the house on the balcony. The first summer they were fine, after the winter they were completely useless. They turned brittle to the point that any slight force would break the things to bits, whereas they were really quite tough before.

    That does not detract from this experiment though, I am most interested to see how this works out in the longer run.

     

×
×
  • Create New...