When accessing a gcode link directly, like this one https://docs.duet3d.com/User_manual/Reference/Gcodes#t-select-tool

The page loads at the top and then scrolls down automatically. It is fast, but not instant and seeing all that text scroll by itself makes me a little sick.

Do you think you could disable smooth scroll when accessing an anchor on that page? Having the page load instantly to the right place would be much more comfortable.

As a side note, when clicking GCode on the left, it doesn't change the URL, which is not practical for bookmarking.

As a workaround, I use this in my toolchange script:

if heat.heaters[2].current > 190
  G1 E10 F1000    ; extrude 10mm

Just to summarize a bit what I learned or confirmed in this thread:

• Always do the math, for belt stretch, beam deflection...
• No design is perfect and it's always tradeoffs.
• MarkdForge kinematic is a nice alternative to CoreXY
• Cross gantry might work with proper design (I will try it for fun (at least a CAD drawing, maybe not the construction))
• Ballscrews are overkill for 3d printer
• Belts can work on Z with gear/brake (or maybe even just 4 big steppers)
• Belt stretch can be smaller than we think, do the math
• There are some 1.75mm bowden drive (nimble)
• This forum is great

@chrishamm Yes that was it. I did follow the update instructions, but I didn't notice there was TWO services, duetpluginservice AND duetpluginservice-root. I enabled the later and now it works.

I am sorry for this "long" thread.

Thanks, your support was great. I built many machines with duet and I'm very happy with it.

@PCR Here is how it looks. I plan to open source everything when the printer is fully operational and tuned, as I am still changing thnigs.

This is not directly duet related, but as this is an amazing community, I thought I would try this forum.

I am designing my next 3d printer, and this time I need to fill all the following requirements:

• large build area, 600mm x3
• can be enclosed to print high temp material
• can move heavy extruder head

I have "solved" many part of the problem yet like which extruder, how water cooling would work, sourcing "cheap" heat resistant linear rails...

Now, I am wondering which frame arrangement to use.

My first design try was something similar to this:

https://3ddistributed.com/3d-printers/workhorse-printer/

Basically:

• Stationary bed, which I thought would be better for large format and provide an easier way to ensure temperature consistency across the chamber.
• "Classic" Cartesian gantry where the X motor moves along
• I thought about using ballscrews as misumi has c-value line which are very affordable
• If I go ballscrew, maybe clearpath servo, but I guess I would try with n23 steppers first
• Of course, duet electronic

Now, while tinkering, I had an idea, how about using an ultimaker like cross gantry arrangement, but instead of 2 rods, I would use 2 profile with linear rails on them. Thus no motor would be moving along the Y axis.

I found this:

https://hackaday.com/2020/08/19/re-imagining-the-crossed-gantry-3d-printer/

So my design would be similar, except with added beefy 4040 profiles for the cross beams (not the bare guides like that).

Basically, the things I am wondering:

• I am still undecided about ballscrews, I looked at different large printer (titan robotic...) and they tend to use ball screw, but big rep doesn't. But going ballscrew for all axles would be possible "budget wise". The print carriage I have designed is about 5kg.
• Is the "ultimaker" style crossed gantry something good that can scale?

I found commercial printers filling my requirements at about $50k so I know I am not trying something "easy", but I would open source everything and I aim at a BOM cost of about $5-6k with all high precision parts from misumi and milled CNC parts.

Hello,

I am thinking of adding an automated way to align my IDEX machine nozzle. I'd like to put a small metal bracket near my bed, this metal bracket would be electrically isolated and pulled high (electrically), the nozzles would be grounded (as all my frame is grounded).

In this sketch you can see the nozzle in gold, and the aluminum piece in gray.

The part of the left is for Z probing, then the hole is for X/Y.

Aligning this piece with the bed (along Z) shouldn't be too hard, this means I can align it once and forget it, then I can easily probes this piece along XYZ when changing nozzle (which I often do).

I know this design can work, as I saw it on the craftbot flow serie of machine, but my question is about duet firmware. Is there a way in the duet firmware to probe a tool offset along X/Y/U ?

I'd like to instruct the duet to move the nozzle above the plate, probe Z first with nozzle 1, set this as Z=0, then move above the hole and a bit down and move along X and Y back and forth, determine the position of the center as X=0 and Y=0 (well, actually not 0, but let's assume this metal piece is at 0;0;0), then do it with nozzle 2, and save offsets.

@T3P3Tony The issue did not yet occur, I think you can consider it fixed, if it happen again I will let you know.

I fully agree with the math thing. I constantly try to do them, for things like beam deflection too. For the belt, I am still considering the high temp option I have.

Yeah, while I have a single Z axis, nozzle can have different shapes, that's why I also need 3 axis, and I guess most system with multiple tools would need such alignment.

I think the sensor (drawn above) could have a screw to modify the Z offset, and after mounting the build plate, you align it with the build plate with a ruler.

This montage would not provide mesh bed compensation, but it is not hard to have a flat bed with a thick bed, thus removing the need for probing everywhere. But it would be nice to be able to mount multiple sensor (like 4 on each corner) and have the firmware use them.

@dc42 Ah, thanks for the name. I'm able to find some. I also considered a vacuum to hold the bed in place and electro magnet but they seem impractical.

Also, is there any build surface, beside glass, that can be used for high temp plastics? As glass is heavy and also cannot be used with magnet base.

I am working on a larger printer with heated chamber and I am looking for a high temperature (200°) bed that has a 700x700mm print area.

The heater is not really a problem as I can use a silicon heater with no adhesive and sandwich it between two aluminum plates. I also though of splitting my bed in 4 heating zone with 4 smaller plate, to help with leveling and thermal expansion. But I am very open to suggestion on this too.

My main problem is build surface. At this size, it becomes harder to manipulate. Also magnet based surface, which I love for smaller printers, cannot be used at this temperature as magnets are usually rated for 150°. I was thinking of creating some kind of drawer that can be pulled out of the printer (my gantry moves on three axis).

@Phaedrux Thanks for the reference. For some reason when searching with google their products do not come out.

@elmoret Email away.

@deckingman Yeah you are right. I'm sorry, I'm a bit under stress and I should have taken more time to pose the actual problem. I sometime forget other people aren't in my head and that it is important to share information. I really appreciate your feedback and I am sorry if I made you lose time.

Yeah, reducing the motor is a good option to increase accuracy of higher pitch belt. I found different 8mm pitch high temperature belts that, I guess, are designed for automotive. I will need larger pulley are they are less supple than smaller pitch, but with reduction on the motor it should be ok.

@deckingman the head is large because the gantry is 1200mm and there is a pellet extruder and a laser on the head. We are working on a technique that improve strenght and smooth the surface with a laser after extrusion. The weight is the head + gantry + water cooling + motors to manipulate the extruders and laser (small "mini axis"). The extruder alone is already 7kg. We have a working prototype of a smaller machine on which we use regular belts with a normal fdm extruder and much lighter gantry. We use high accel for laser moves.

As a side note, GT2 12mm wide seems to require custom made pulley. I cannot find off the shelf clamping pulley larger than 9mm wide for 2mm pitch. I use mostly McMaster and misumi. I found some chinese pulleys on ebay and alibaba but they are all set screw.

@mendenmh Yeah that's one possibility, but that's more hassle for tensioning and such.

@deckingman I used 1g as max accel as it gives plenty of margin over the accel I am going to use. At 1g, it's 250N, with a 20mm diameter pulley, it's 2.5N/m torque and 1500RPM for 500mm/s max speed, which is about 400W (for some reason, most belt sizing guide I found from manufacturer uses watt or HP), and for this gates recommend 25mm wide belts. I also did the math in the gates belt sizing guide.

@deckingman I actually have a design with rack gears, but it requires moving motors and some axis requires multiple motors that have to be synced. Belts let me have one motor per X and Y axis. For such a large machine I though having direct mechanical coupling was better because if motors unsync for any reason it could cause major damage.

@deckingman my moving mass is 25kg and I'll aim for highest possible accel. I use nema 34 clearpath servo.