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brett-bellmore

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Everything posted by brett-bellmore

  1. Thanks, I'll have to check that out, too, in the coming year. Do the mechanical properties seem any different from the usual PLA? Harder, slipperier, anything like that? Or just standard PLA that happens to conduct?
  2. 1/4 pound of F-electric filament We're ordering a small roll of it to try, for a fixture that requires an electrical contact. It's a form of PLA, which we haven't been terribly happy with. Sheds particles when it wears, which mess up our parts processing. On the other hand, the nylon we've been printing these out of is non-conductive, which complicates things for us, because we need electrical contact for parts sensing. This stuff is obviously conductive enough for our purposes, but in light of the above, how are it's mechanical properties? Wear resistance? Anybody have some experience with it?
  3. As above, "45C bed, Elmer's glue wash, 247C nozzle, no fan, 100% speed." No brim or raft, 0.06 steps on z, 1mm bottom and top thickness, 30% infill, 50mm/s print speed. Yes, it did look better dry, and I'm putting the roll back in it's bag over the holiday weekend. The work related prints were solid, looked 100% dense/translucent for a mm or so from the bottom, white after that. The prints I've done since the material has had a chance to soak up some moisture are more frosty looking. But nothing like the 618 was under the same conditions. (That came out of the nozzle like shaving cream!) I'd say it's easier to print than the 618, maybe comparable to the Bridge, but supposedly twice as strong. But what really impresses me is that it prints so well 'wet'. And, like I said, it didn't warp. We are going to look into modifying our printer to have a heated enclosure. That the material looks so much better right by the bed, warm, tells us that would be a good idea.
  4. Just a simple part, a ring to help hold a flag on a small flag pole. Probably would have printed a little better if it was dry, the roll was sitting behind the printer all weekend, instead of in it's dessicant bag. Still, not bad for 'wet' nylon. Edit: The next day, still without drying. A 76mm diameter, 144 tooth bevel gear. Printed with 25% infill. Didn't pop loose or warp, even after removing it's dead flat.
  5. Unfortunately, business related print, and my employer is pretty paranoid about IP. I'm gonna be buying a roll of the stuff for my own use, (We engineers are permitted to use the printer for 'government' work as long as we buy our own consumables.) and I'll post a picture of my first print in it that's not work related.
  6. The 910 finally showed up, and I set up some small fixturing components to print overnight, 12 in all. Beautiful! No tendency to warp off of the bed, crisp sharp edges, relatively little bridging between the parts, (like cobwebs, really.) 1.25% uniform shrinkage. Not really enough to worry about on these particular parts, might have to compensate for it on larger components. 45C bed, Elmer's glue wash, 247C nozzle, no fan, 100% speed. Our printer has a piece of transparency taped across the front for a door, and a large plastic bag over the top, to suppress drafts. Did notice that the prints were nearly transparent for the first mm or so, and then turned milky white. This suggests to me that we need to move up to a heated enclosure.
  7. We've tried string trimmer, Bridge, 645, and 618. So far we found all of them easy to print with except the 618, which has been a real pain. Not that we couldn't successfully print it, but we weren't happy with the results, and don't plan to restock when we've used it up on non-critical jobs. Too moisture sensitive, and warped especially badly. Not one of our 618 prints failed to peel up on at least one corner, (Which hadn't been a problem with the Bridge.) until we tried an Elmer's glue wash on the glass. That held it down, but the quality of the print was still inferior. A roll of Taulman Alloy 910 was supposed to arrive today, but apparently nobody in the front office made a run into the post office to check our PO box. I should be trying it out tomorrow. I'll let you know how it works out, I hear good things about it.
  8. Replace that dial/button with a separate selector and button. I'm tired of pressing when I mean to turn. (Periphrial neuropathy, I can't judge how hard I'm pushing very well.) A better feeder. Metal hot end. And, a non-cantilevered bed. Not so concerned about enclosing it; We wrapped the top in a small garbage bag, and taped a transparency sheet across the front, and eliminated all the drafts.
  9. We just got in some Taulman Nylons, and tried the Bridge Friday. 245 nozzle, bed at 45C with blue painter's tape. 0.06 z steps, and 30 speed. Came out beautiful. Looks almost fully dense, nice finish on the surface, and printed for 18 hours without a glitch. I'm looking forward to trying their other nylons. Looks like this material might become our go-to material for structural uses. We store our fillament in zip-lock bags with a dessicant pack and humidity monitor strip, but right now once they're in use, they're just sitting out in the open. We have plans to build a dessicant cabinet with multiple rolls already fed into tubes that will reach to the feeder, so that all our materials can stay dry even through long prints. I think my only complaint is that the Taulman came on rolls with such small cores, wouldn't fit on the back of the Ultimaker. No biggy, though, just set the roll on edge next to the printer, and it unspooled fine. I wouldn't try that with most materials, but Nylon handles that treatment fine.
  10. They are the only supplier we've had this particular problem with. Maybe not enough additive. We're shortly going to be moving to a new building, with a dedicated area for the 3d printer(s), rather than the corner of my desk. This is going to include moving the fillament storage to underneath the printer, in a dehumidified cabinent. (With tubes leading up from the cabinet, to keep the fillament dry). I think this will help somewhat, as the current fillament path stresses the fillament unnecessarily. Might be worth experiementing with rewinding the fillament onto much larger cores, and annealing out the stress. I wish they sold it that way to begin with, it's just too tightly coiled for a brittle material.
  11. Anybody else have experience with Prototype Supply's PLA? We got a roll of black PLA off of them, and while the prints come out as crisp as you could ask, the filament is horribly brittle. We've had to take the boden tube off several times already to clear filament that broke after the feeder on retract, and one time we even had it snap between the roll and the feeder. A pity, too, because the prints did come out really nice.
  12. Guess I'll reformat the SD card, then, and try again. Perhaps a watchdog timer is needed, to abort automatically when this sort of thing happens. Some materials would make a real mess of your nozzle if they sat at extrusion temperature all weekend.
  13. Just came back to work after the weekend, expecting to see a pop can sized print that was projected to take over 20 hours. Instead, I found it had just stopped in place 1 hour into the print, with a burnt spot where the nozzle sat all weekend at ABS extrusion temperature, and the readout right where it was an hour into the print. I aborted, and it went right to home position like nothing out of the ordinary. Right now I'm doing a material change, to see if the nozzle is just one block of carbon, which is what I expect. (Lucked out, I guess: It extruded black, then tan, then cleared up.) Data error on the SD card? Processor glitch? Any ideas?
  14. We have successfully printed using 1.75 material. It tends to meander in the boden tube, and retracts aren't immediate, but it prints. However, I expect this is highly dependent on both the rigidity and coeficient of friction of the material. And I wouldn't do it as a usual thing, it probably wears out the boden tube much faster. But if you've gotten in a few feet of a sample material in 1.75, and just want to try it, it can work in the UM II without mods. Depending.
  15. Final report for now, we've about exhausted our evaluation sample. We printed a 12mm square solid part, 25mm tall, and periodically tuned the nozzle temperature up, marking the transitions. Started at 240C, ended up at 260. With each 5 degree increase in nozzle temperature inter-layer adhesion improved. It never reached the point where the part could not be split, but by 255 degrees, the amount of force necessary to split it was comparable to what was needed to cut it in any other direction, so, good enough. It's obviously never going to be anisotropic. I don't think this tells me that it needs to be printed very hot. Rather, a heated enclosure or full height skirt seems to be called for. Maybe less fan, too. Unfortunately, out of material for now, so we can't test these other variable. I like the material, though. It's hard and slippery, prints very crisply, and the wear resistance claims seem quite plausible. Think we'll pre-order a roll or two.
  16. We've run off several more parts, and put them into service. As we've pushed the nozzle temperature up, inter-layer adhesion has improved, but it still isn't great, the parts fail in service by delaminating. I guess the next thing to try, short of a heated enclosure, is printing a full height skirt around the part as we go. Unfortunately our evaluation sample is starting to run low. Anybody else have experience with this to report?
  17. I recall some of the early rep-rap work involved using extruded solder to make conductive traces. The biggest problem seems to be that it beads up on you. You couldn't use a eutectic solder, you'd need one that only partially melted, so that it went from solid to paste, not liquid. It's something I've wanted to try, but we'll have to get a backup printer and multiple heads before we do any experiementing of that sort.
  18. Used the recommended settings, came out the crispest looking print I've gotten yet. Excellent definition, and the surface was noticibly harder than ABS or PLA. Alas, it was the plastic equivalent of mica, the layers were quite strong, but the print could be split between them, right down to individual layers of plastic. We are now trying a second print, with the head at 230 instead of 220, to see if it remedies this. I'm thinking you might want a heated enclosure for this material. Delamination seemed to be less of an issue near the heated bed.
  19. Doing a test part right now. No, the 2.85 sample didn't arrive, we just decided to see what would happen if we ran 1.75 through the current setup. It's wiggling a bit in the boden tube, but extruding just fine. Not ideal, but we should get a part out of it, to see if we like the material.
  20. I suppose that will work, sort of. But if the material in the extruder will burn at the extruding temperature of the material you're going to, and the material you're going to is solid at the extruding temperature of the material that's in it... Then I guess you've got a problem anyway, since the nozzle doesn't completely empty during a material change. If we get into really high temperature and low temperature materials, we might need to change to something intermediate in between, to make the change. Just struck me as strange to ask what the material was after starting to extrude it.
  21. We're just about to try out a new material, and an issue came up: The Ultimaker doesn't ask you the material, when changing materials, until *after* it has been pushing it through the nozzle. Suppose you were to switch from a fairly low temperature material, to a high temperature material? Here's your extruder trying to push the new material through a relatively cold nozzle! Why doesn't the firmware ask about the incoming material before pulling it in and attempting to extrude it?
  22. Speaking as a design engineer, that's fate. I send perfection to the shop, and they come back with complaints.
  23. Yes, had a brim. And glue stick. Printed it in the default orientation. It has radii on all the edges, and as the instructions said not to activate "support", they are unsupported. On my machine they start curling up. The altered version, without any radii on the bottom edges, is printing just fine so far.
  24. I am currently *trying* to print the arm from Robert's latest feeder. I say "trying", because the large, unsupported radii on the bottom surface are curling up as the print proceeds. The table is actually deflecting visibly as the nozzle passes over them. And... Yes, the nozzle just passed over one of those curled up edges, and knocked the unfinished part loose. The print died at 1.26mm thick. I'm adding material to the base there to get rid of most of the radii on that side of the part, then I'll try again. Might not look as good without those radii, but I don't expect I'll be spending much time looking at the back of the feeder arm. Has anybody else had this issue with the feeder details, or am I doing something wrong?
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