foehnsturm

I used this one http://www.ebay.de/itm/Schneckenrad-Schneckengetriebe-Schnecke-Modul-0-5-Messing-/201016508336 scroll down for a table with measurements. While the bigger one would fit directly on the shafts it might be too wide to accomodate in the gearbox together with the drive wheel.

Frankly, I had the impression that things changed when the company website was relaunched. Aimed for a super slick design but harder to use than before. But I didn't care much. Then, UM copied the M*bot move with Extended and GO. Driven by sales and marketing departments - understandable but no technical progress. Then they cancelled dual extrusion "Doesn't match the UM experience .. " Now the forum redesign focuses on likes, badges and avatars. Even without reading a single line of text the message is: "Look what a big community of great people". There is nothing wrong with that ... if the core functionality doesn't fall behind. In short, 90% marketing, 10% R&D. I'm feeling a lack of substance.

Well, 1:40 compared to 1:15 is less than half the size. With 1:15, a MK8 drive wheel and the gear wheel are more or less the same diameter. This allows for a different assembly. .. not sure if you can see much without a damned zoom function.

What about ditching the "Like" feature at least for topics? Select --- most liked --- most viewed --- most commented What for, besides personal vanity? Utterly nonsense! That's not youtube here. You may like a print or an answer (but this would be covered by "best answer"). Too much social media shit ...

So, what is your experience with changing from 3mm to 1.75mm filament? I'm thinking about that too, because I could design my NEMA8 direct extruder considerably smaller then.

Well, to me the spam issue is the acid test. If UM cannot fix this within almost a week they won't fix anything else in reasonable time. Either the entire staff is on holidays or developers are hopelessly overtaken or the software is so badly designed that it takes ages to implement a fix. Either way this thing would be a stillbirth.

Wow, never saw a NEMA8 with that kind of shaft. The ones I bought feature a shaft of 6.5 mm. Most simple fix would be some spacer tubes below the motor. The odd angle is intentional. It moves the gears together close enough and increases the distance between the (hot) motor and the upper part of the printhead.

... agree

and please reduce that crazy number of mini avatars (100 to 200 per page) I'm feeling like in a bubble tea shop ... better like this:

Another point: I suppose your web designer fell in love with css transitions. But most of them are a perfect example for the unnecessary cognitive overhead I mentioned already. One (the worst) example: In overview, when scrolling down, the top bar first becomes blue (and so attracts attention) and just some fractions of a second later the "Ultimaker" line slides to the left and the whole blue bar slides to the top and disappeares. What an incredible nonsense! You call for my attention to watch you something hiding epically which would simply disappear anyway due to my own (scroll down) action ... I'm sorry, but 90% of this fancy transition stuff just reminds my of dark PowerPoint times.

To me it looks like the "Prints" section is supposed to take that content now. However, if so the default sorting order there makes no sense. I should be latest first not best rated first.

Actually I'm unintentionally running a "new" 12V cartridge and an "old" (I suppose 24V rated) cartridge at the same time with my tool changer. Took some time to discover that ... PID autotune was hard ;-) Though obviously not perfect, it's working quite well, but only with reduced PID_MAX and BANG_MAX settings in Marlin.

True, I won't spend much time on it. Like your attempt this is more or less a message to UM how things would work better Just noticed that the first replied-by-avatar not always is the last one who replied but somewhat close to ...

Careful, it's a slippery slope ;)I've been using it for many years and I use it quite often to tweak things to the way I want them. But it's fun and a good css exercise. Just changed the "Replied by: [numerous avatars]" to "Last reply by: [first of avatars]" ...

Never used greasemonkey before, but I start to like it ... Removed the "replied by" part and set the second line to font-weight: normal. Now the less important part is also less prominent. ...and redirected ^https://ultimaker.com/en/community$ to https://ultimaker.com/en/community?sorting=latest

It works without cutting the shaft if the adapter doesn't waste much space longitudinally. The spring is a standard extruder spring: OD 7.5 mm, wire diameter approx. 1.2 mm, 20 mm long.

Cognitive overhead Concerning the the top bar and several other features of the new forum I'd recommend a thorough reading of Conklin's "Hypertext: An Introduction and Survey":P ... as valid as ever. That's what I did when I wrote my diploma thesis about a hypertext browser (yes: "hypertext", Tim Berners-Lee came up with the term world wide web just when I was finished ;-)

Still somewhat struggling with the new forum ...

Just revisited KISSlicer and bought a Pro version, good to have more than one slicer to compare. As KISS offers custom gcode for "Select new extruder" and "Retire old extruder" it's easy to split the change movement pattern into the drop and pick part. A nice side effect: the toolhead status is always identical at the end of a print (both parked). One leave was actually sliced with KISSlicer.

BronzeFill @ 185°C and red PLA @ 205°C, 0.15 mm layer height The white one was just a test run. Will print some more, then they'll go into the vibratory polisher.

You've read correctly between the lines :wink: The UM printers are one of the best to have and I like the attitude of the people there. However, their emphasis has been on reliability and quality the last two years not so much on cutting edge technology. I suppose (I hope) they will leave "Tim Cook mode" and enter Steve Jobs mode with the next things they come up with. But I've no idea where they're heading. If UM does it's homework with dual extrusion a tool changer conversion might become obsolete for UM3s because most people will be happy with a well working dual solution as you correctly said. As I've two businesses running I will not start a third one with a new printer. Maybe in two years with next generation electronics and firmware ;-)

The first NEMA8 I tried was actually the standard type which is available everywhere. While it worked, it skipped steps at higher speed. In the "UM with direct extruder ..." topic I wrote about that in more detail.

I'm currently thinking about the next iteration of this design and would like to discuss some points. No bowden? To my knowledge, a bowden setup might not be able to offer the level of extrusion control which is required for perfect multi extrusion. Any examples for really well working dual bowden systems? If not, it's only direct drive (NEMA8) or flex. Size matters As this approach will typically use some printing area for parking unused print heads they should be as compact as possible. My first design features a footprint of 32 mm x 41 mm. The smallest print head I can imagine with a NEMA8 direct drive would be 22 mm x 30 mm. I think I've to go for the most compact design. Of course things would be different if the whole printer was designed for a tool changer. 1.75 instead of 3 mm? NEMA8 and flex both require a gear reduction in the the range of 1:40 to drive 3 mm filament. With a gear module of 0.5, the big 40 teeth gear wheel will be approx. 20 mm in diameter. This is kind of a hard limit for downsizing the print head. With 1.75 mm filament some 1:15 reduction should be sufficient, which corresponds to a 9 mm gear wheel. The 22 x 30 mm2 will only be doable with that. Additionally, there would be almost no unwanted forces exerted by the filament to the magnetic mount or the parked print heads. Your thoughts?