Gauging interest in group project  

RE: Gauging interest in group project

I'd be interested, but not sure how much time I can dedicate to it. I'd really like to be able to change hotends & extruders without having to mess with the entire X carriage. Ideally, without recompiling firmware if just popping a V6 back on.

RE: Gauging interest in group project

@bobstro

Me too.  I am really surprised someone has not done it yet.  It has to be possible.  

RE: Gauging interest in group project

I might be interested in something that would let me run something like a Dremel tool with the I3, kind of like a mini CNC mill.

At the local 'makerspace' they have a CNC kind of engraving machine which is more or less like this.  Since they opened back up, they are allowing only one person in the lab at any one time, so the chances of getting in there to use it when I want it are low.

RE: Gauging interest in group project

I will think about a design that will work with the x-carriage.  If you can do the same, we will collaborate on this thread.  

RE: Gauging interest in group project

One of the unexpected pleasant surprises with the Sidewinder has been the extruder. They use ribbon cables (perhaps questionable) to the extruder assembly, and there's a small circuit board there that the thermistor and heater cartridge plug into, along with the fan and an LED. Leads are all very short (2-3 inches max) and tidy. The real bonus came when I realized I could remove the ribbon cable and 3 screws and have the entire extruder & hotend assembly in my hand. Makes maintenance a real breeze, and extuder and/or hotend swaps are straightforward.

I'm hesitant to modify my Mk3 too much since it's so reliable, but I'd love to mount a Titan Aero extruder with a V6/Dragon hotend and the 3D Solex nozzles to see what it can do.

RE: Gauging interest in group project

@bobstro

That is exactly what I am thinking.  There is only one way to find out.  

RE: Gauging interest in group project

I'm also wondering if there's a way to do something like the ribbon cables, but using more robust cables. The choice of modular connectors is also important.

RE: Gauging interest in group project

@bobstro

I do think that is possible.  

RE: Gauging interest in group project

@charles-h13

I have modified a Bondtech extruder so that I can at least change the hotend quickly without having to partially disassemble the extruder.
When changing the hotends, only the heating cartridge, the thermistor, fanshroud and a locking device have to be removed so that it can be removed.

https://grabcad.com/library/prusa-mk3-bt-1-8-bmg-extruder-v2-1/details?folder_id=7128539

However, I find the idea of constructing a kind of Z-axis adapter interesting. I did the same with my CNC-milling machine, so that I can quickly install different spindles or for example a laser head or something similar.

RE: Gauging interest in group project

I like that clip-on style with the angle bracket which looks like it will assure a very solid mounting with negligible play.

I took a good look at the MK3S while it was printing and honestly, this looks far more complex than I first thought.  That's quite a 'snake' growing out of the existing extruder, and if I remember the wiring during the assembly, it will not be easy to massage it into something that adapts easily to a removable extruder module.  I figure that there needs to be a connector, and that connector has to be very solid and reliable, as in not introducing any resistance or noise while that 'snake' is flexed during printing.

First of all, I want the printing to be just as reliable as it is now.  First rule, do no harm!

RE: Gauging interest in group project

@jsw

That would be a requirement.  

RE: Gauging interest in group project

Let me ask a related question please.

What, specifically, are the advantages of using a different (single) extruder other than the stock extruder with the V6 hotend?

What requirements are there in any common prints that cannot be met with the stock extruder and hotend?

RE: Gauging interest in group project

Posted by: @jsw

[...] What, specifically, are the advantages of using a different (single) extruder other than the stock extruder with the V6 hotend?

A geared (e.g. E3D Titan) extruder can make working with flexibles easier. The existing extruder has a max feed limit that is below what the E3D V6 hotend can process (~70mm^3/s). With a higher throughput hotend, this puts a maximum on top speeds/throughput.

What requirements are there in any common prints that cannot be met with the stock extruder and hotend?

Flexibles can be easier to work with (though the Mk3 is pretty good as-is). When working with larger nozzle sizes, you encounter limits with the hotend capacity to heat and move plastic (addressable with different hotend and/or nozzle designs). Newer hotend designs are more robust when swapping nozzles (less dependent on bracing the heater block with one hand while unscrewing the HOT nozzle with the other) and less prone to twisting. This accounts for a large percentage of the "leaking block" problems from poor nozzle installation.

RE: Gauging interest in group project

For me, I just like to tinker so testing extruder on a printer is fun for me.  

RE: Gauging interest in group project

@karl-herbert

Interesting.  

RE: Gauging interest in group project

I've got a Dragon hi-throughput hotend coming. For now, it's targeting the Sidewinder (along with a Mellow "Wind" extruder) but it would be interesting to swap it in. Not on a real timeline, so this may take months.

Now if we really want to get fancy, design this so the hotend can be moved between different printers with compatible adapters! 

RE: Gauging interest in group project

I might just make one that I can remove with screws.  I just want to test hotend.