uncle_bob
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Posts posted by uncle_bob
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Hi
Can I rig something to hold bigger spools? Sure. The main point of buying a UM is that it *can* all work together. The RFID works with their spools and integrates back into Cura. I don't *have* to use that feature, but I can use it. If they come out with a yet larger printer that pretty much requires you to rig the filament feed with something from somewhere they break that operating model. You buy the printer from them and then go off and buy this and that to actually be able to *use* the printer. Yes, I'm in the middle of a project on the UM3 ext that is running 800 to 1200 g for most of the parts. That's most of a week per part doing the printing. It's been going since January and likely will complete by June. This is not just speculation. Spool capacity *is* an issue as they ramp up the size of these printers.
Bob
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Hi
No, not at all useless. The issue is 750 g filament spools and how to manage them with a larger build area.
Bob
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Hi
I don't have to print much of a shell on a large part to run through 700g of filament on a UM3 ext. Boost all the dimensions by 1.5X and the volume goes way up. It's still not real clear to me that *all* the dimensions go up 1.5X. The new beast may be a cube. If so, the parts will be no taller than a 3 extended will print. Yes, this is quibbling about 2.5 X vs 4X on the volume.
Bob
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27 minutes ago, kmanstudios said:
Would that not depend upon what you intend to make?
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True, but there are not a lot of things that are bigger then 300 cube that take small amounts of filament. If the part fits in a 200 mm cube ..... run it on your existing printer
Yes, I do realize that somewhere out there somebody prints nothing but vase mode .... most of us aren't quite that mode specific.
Bob
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Hi
Basically I was making a point that anything much over a 300 to 350 mm cube is getting a bit crazy ....
Bob
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Hi
..... but if *everything* scales with the sticker
Bob
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Hi
There are some practical limits in terms of how useful a larger machine is. Going up to 300 x 300 x 300 is rational. That way you don't have to bother quite so much about fitting an object vs how you want the layers to run. 3X larger gets you into crazy land. The rods and belts would all have to be monster sized for it all to work out in the video. You also need at least 2 KG spools to feed the beast (I have data on 500 x 500 x 500 .... 600 x 600 x 600 would be a bit worse) for full sized prints.
Bob
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6 hours ago, Daid said:
It should be relatively easy to adapt the "pause at height" post processor for this goal, instead of height it just has to look at filament usage.
Hi
That's my hope. With something like pause at height built into Cura at lest there is a way to get a big print done with a large(r) printer and standard filament spools. The ideal case would be to allow the user to input a filament amount (or a series of amounts). That way Crazy Bob who goes to 751 grams on every spool can do his thing. Someone not quite so insane can drop back to 740 or less. It might also come in handy for using up piles of partial spools.....
Bob
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Hi
So .... to get back to the top of this ... what is needed is a Cura "something" that can put in a pause based on filament used. More or less, tell it that I want to stop before 740g and let it figure out the best point. If this is a bigger printer, something like that will be needed. Since I *know* that a 1,200 g print will run over a 750 g spool, I need to do something. Sitting and watching the spool is a really boring thing. Ask me how I know this
Bob
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Hi
The ideal is to star away from a wall in an infill region. That's a bet you may win randomly, but you also can loose it. The best solution would be for Cura to work out "this is a fine place to stop" and tag that. Then do an orderly stop there. That's what drove my initial suggestion that you pre-program an "end of spool" into the gcode straight from the start. No matter how elegant you try to be with a new load of filament, the first extrusion will be a bit of a mess. That's why we do various things at the start of the print to get things going ....
What seems to happen is this:
The printer is doing a move
*and*
The printer is running the extruder
Both are supposed to match each other. Both should be a 1:1 match for each other. In the real world, not so much. When it resumes in the middle of this or that it either over extrudes or under extrudes. Neither one is what you want. On some printers ( not UM brand ) the results are pretty horrible. My guess is that there is more to this than a simple resume ....
Bob
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Hi
If you are going to depend on the sensor to do an orderly shutdown, it definitely needs some "room" to stop things. I have a couple of "other brand" machines with sensors on them. When they trigger (properly or not), the results are very hit or miss. If it's in the middle of something critical, they mess up. I really can't see any way around that happening with an abrupt halt. The next gotcha is making the firmware smart enough to work out when the layer (or feature) is done. For a layer you could watch the Z motion. For a feature, it is a bit more complex. Z hopping still might let you know when to do what. If the layer is a full flat coat over a (let's just guess ... ) a 300 x 300 bed - that could be a lot of filament. Toss in nonsense like using a 0.8 mm print core and 0.5 mm layers for big parts and it's even more filament.
Bob
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Hi
Looking at the teaser video, the spool holders and "all that stuff" look a lot like stock Ultimaker parts. Unless they are also coming out with 1.5 Kg "standard" UM spools, I'd guess it's set up to run the stock 750 g ones. Indeed you *can* get bigger spools on the back of the printer (some, but not all brands). I would think UM would like to keep you using their filament for your giant 2 1/2 spools of filament prints
. Besides, it's only code. Coders all work for free don't they? (Yes, I used to do that for a living).
Bob
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Hi
If it is a "super sized" UM3 Ext then they better get on to the firmware / Cura guys for an added feature right now. A 750g spool of filament is a bit small for that sized machine. You will need a way to tell it "stop and yell at me after you have printed XXX grams". Not a big deal as features go, but very much needed. A filament runout sensor that works would be another option. The gotcha there is that it stops in mid motion. What you really want is an orderly stop once a layer is completed. The whole "halt in the middle of it" thing when the sensor fires makes for messed up prints .... I have empirical evidence ....
(Yes, this is a feature that might come in handy on a UM3 Ext as well ....I have data on that as well
)
Bob
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Hi
A drafty garage that is at 5C now and 20C later in the day is *not* where you want to print ABS.
Bob
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Hi
Almost any time you hear "snap crackle pop" as the filament extrudes, it's moisture. There are number of ways to try to dry out filament. I prefer a vacuum pump and sealed pot. I use a very modest amount of heat ( = a warm room, not a hot plate). Some filaments will dry pretty well in a few days. Others seem to take a *long* time. Mr Google will supply you with lots of details .....
Bob
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Part height matters a lot with ABS. A part that is several inches tall will often have separation part way up the sides. X and Y also matter. A part that is the size of the build plate will be *very* tough to keep held down. Unfortunately it is not just an issue of holding during the print. If you have the optional door on the printer, a pretty big part can make it through the print process. It then may warp / crack as it cools down. Bottom line is that there is a practical size limit to an ABS part running with this or that brand filament and this or that profile.
Yes, I do realize that somewhere out there somebody prints nothing but vase mode .... most of us aren't quite that mode specific.
Ultimaker S5 | impressions & opinions
in UltiMaker 3D printers
Posted
Hi
I do believe you have hopped into the middle of this without reading the earlier posts. My point is not at all that this is a junk design. What I am proposing is that a pretty simple fix be implemented in Cura to work around the issue. Go back and check out the earlier posts ......
Bob