Mini Network Farm , is it possible yet ?  

@MKEMike

@MKEMike

So far I have never decommissioned a machine. I've found there's no such thing as "beyond capable maintenance" in my shop. We do all of our repairs in house, and we've never met a bug we couldn't fix. The worst rash of failures was with the MK3S in that the x and y idler bearings are starting to disintegrate under the loading of the belts. Those machines have around 10,000 hours on them. 

I print for profit at about 50% average capacity through the year. I do have 30 day preventative maintenance procedures.

My oldest mini has about 1,000 hours against it since fielding in November. The farm processes about 100Kg per month in mostly direct-to-consumer work, and some business clientele.

For the most part, the only firmware mods applied were to reverse the filament sensor logic (I ported over the MK3S+ R6 extruder design) and reduce the e steps per mm. Same for the slicer, the only thing I've adjusted is I removed the 170C wait cycle after the Super PINDA upgrades.

As to the rest, best of luck. I don't have time so sift through all of that, and some of it is my "secret sauce" I'm not willing to share. 

Farms

@MKEMike

Great questions, I look forward to the answers from others.

For me, I do monthly maintenance and I visually inspect them every day.  I look for visual breakdown.  Monthly, I do the stardard Prusa recommended maintenance.  Outside of my last 3 Prusas (2 Minis and 1 Mk3s), my printers paid for them selves within 1 year.  The remaining 3 are new (6 months).  I also have two Creality printer and two Anycubics that are pending paying off their value.  The Creality printers are maintenance heavy and will probably never pay off.  The Predator and Chiron had paid themselves off 4 fold in 2 years.  I also have two new BIQU BXs that I am breaking in.  The 13 Prusas (5 Minis) are by far the easiest and best investments for me and what I print.  

It always amazes me the varied experiences with the Mini.    

Location

@djkirkendall

Where is your print farm (region)?  I am just curious.  Would you entertain visitors to look at improving their own operations?  

Awesome farms guys!

@djkirkendall and @cwbullet

You guys sound like you're doing great.  I've been looking at starting up a very small farm (maybe 2 Minis or 1 Mk3 to start) to print enclosures and mounts for a few different circuit designs.  I do not see having short-term quantities of any one design being anywhere near where doing custom injection molding makes sense.  I figure that having a small, but continually refreshing stock of enclosures and mounts will allow for the company finances (side-gig, new company, self-funded) to be focused on getting the circuit boards manufactured and components purchased in quantities where the pricing makes sense.  For many electronic components, qty 1000 in one order is the same price or less than two separate orders of 100 each.  So between that and avoiding shortages later, you end up with a good amount of money tied up in parts and WIP inventory.

  Of course, I also worry (OK, dream) of things taking off and having to scale the farm quickly, and of course not getting into a situation where under-spending at the beginning means double-spending to replace later.  That's where I'm debating more Minis vs fewer Mk3s.  My Mini has been really solid, but I don't have to depend on it for daily money-making production.  Mk3s are well proven in print farms, but when you have fewer of them (due to cost), even one being down is a higher percentage of the farm not producing, and risking falling behind on production.  

Drop on by

Posted by: @cwbullet

@djkirkendall

Where is your print farm (region)?  I am just curious.  Would you entertain visitors to look at improving their own operations?  

I'm in SoCal, and I give tours fairly often. People usually get stuck on the first rack. 

RE: @MKEMike

I took a slightly different approach. I picked a niche in which it would never be feasible to scale to a point where IM parts would work (getting stuck with 10,000 parts that will never sell). 

Additionally, with 850 original items in 20 color support resin ops and molding/casting are out due to upfront cost and storage requirements. 

I've had to shut down my storefronts every year during christmas as demand usually overruns the farm. Last year I had to shut down for 2 days as I overran our administrative throughput. 

We've been refining our processes such that every print takes less than 20 seconds to start, 10 seconds to harvest, and no more than 3 minutes to finish/assemble. OctoFarm was a huge step in the right direction, and 3DPD served as a testbed/source of requirements. I believe I/We are still acknowledged in the about section on the git. 

Wow

Posted by: @djkirkendall

I took a slightly different approach. I picked a niche in which it would never be feasible to scale to a point where IM parts would work (getting stuck with 10,000 parts that will never sell). 

Additionally, with 850 original items in 20 color support resin ops and molding/casting are out due to upfront cost and storage requirements. 

I've had to shut down my storefronts every year during christmas as demand usually overruns the farm. Last year I had to shut down for 2 days as I overran our administrative throughput. 

We've been refining our processes such that every print takes less than 20 seconds to start, 10 seconds to harvest, and no more than 3 minutes to finish/assemble. OctoFarm was a huge step in the right direction, and 3DPD served as a testbed/source of requirements. I believe I/We are still acknowledged in the about section on the git. 

Woah, I can't believe you're on here, super cool. I'm also impressed at how much you've grown with such an interesting niche. My parts I'm printing in my farm are more function than fashion - they're not pretty, but they work - and it's encouraging to know that such a market exists. I don't think I could have the patience to optimize settings to get such incredible results.

I definitely need to check out Octofarm now. 

what a wealth of information

@djkirkendall, @cwbullet, thank you for all of these insights. I think this can give confidence to all the hobbyist, seeing that even the "torture tested" printers only experience issues that are very fixable, even though the issues might make them unsuitable for larger scale operations, it might be a good starting point.

This provides a nice confidence boost for being able to keep my MINI run reliably and being sure that if the issues that @djkirkendall had, I'd be able to resolve them since he's already paved the way 🙂 .

Honestly, seeing the prices of used MINIs, I think somebody who already has experience running one personal MINI could easily buy a few more to start out with commercial printing and down the road, you are not bound by that purchase, you can add other printers, or you can flip the MINIs and get something else. Plus, if you want to stay with Prusa but don't like the 8bit board and other bit outdated things on the MK3, XL and MK4 would hopefully be out by then... 🙂 .

RE: I don't mean to be a fountain of negativity......

There are some pros to the mini I should mention now that I got all of the design...... challenges... out of the way. Here's some fan bullets to even things out a bit. 

1.) Power consumption is phenomenal. I can run 4 minis off of a 1500KVA UPS for about 40 minutes, and those 4 minis draw the same power as 1 Ender 3.

2.) The form factor is great for what I do. These print about 80% of my offerings, and I can fit 20 to a 5'x7'x18" steel rack with 4 shelves and still only pull about 13 amps even with Raspberry Pi's (bluetooth and wifi disabled). I can fit 16 on a 5'x5'x18 steel rack. 

3.) The parts are common (now) to the MK3S+. With my Extruder/Hotend redesign all parts are common amongst the Prusa Family printers. 

4.) Aside from the random serial disconnect, it is an extremely reliable machine when fitted with an E3D and MK3S+ extruder. 

5.) The Super PINDA did exactly what it was supposed to. I rarely have to adjust nozzle height regardless of ambient temp. 

So, in closing, the Mini can be used with $60 worth of mods in a farm setup. As soon as the random serial disconnect bug and filament sensor operation on remote bugs are sorted, this will probably be my most productive racks. 

E3D Note: I only swapped the sink and heatbreak, I bought the metal-only kits direct from E3D. The heatblock, therm, cart, and fan are stock.  

Thank you so much!

@djkirkendall @cwbullet Amazing information! Thats the reason why I love this forums so much. I've been running a 13 prusa printer farm for 3 years now and have been starting to notice all prusa mini problems you have been mentioning. Been thinking of ditching the prusa mini format and keep adding more mk3s+, however I am quite eager to see the mk4 and XL printers. 

List your mods plz

@djkirkendall

Please list your mods in a list format, I notice you've listed most of them in this thread, but for future reference (So I can copy a link to your reply for other newbies) I'd like to see it all in one list. Alternatively make it a paragraph and I'll format it.

Maybe someday

I haven't decided if I'm going to release that just yet. I worked very hard on it over the last few months and I have completed my testing with great results. This might just stay in my bag of tricks. 

e3d parts

Posted by: @djkirkendall

E3D Note: I only swapped the sink and heatbreak, I bought the metal-only kits direct from E3D. The heatblock, therm, cart, and fan are stock.  

thanks for sharing your information can I ask is this the heatbreak as it doesn't state for the mini , I did consider the bowdon?

https://e3d-online.com/products/prusa-specific-heatbreak-mk2-mk3

and also the heatsink ? https://e3d-online.com/products/v6-1-75mm-heatsink-with-coupling?_pos=1&_sid=c64a14303&_ss=r

Thanks 

RE: E3D Swap

Use this: https://e3d-online.com/products/v6-hotend-metal-only?_pos=1&_sid=4180d7c32&_ss=r

And of course bowden. 

RE: I appreciate the response.

thanks alot only have direct drive so will message them to see if they have any in the near future.

RE: conversion print

looking to go down this route but like you when you have to upgrade multiple printers it soon becomes costly 

https://www.prusaprinters.org/prints/28046-prusa-mini-v6-conversion-upgrade

remix

https://www.prusaprinters.org/prints/67779-prusa-mini-v6-hotend-adapter-fusion-360-fix/files

Needs work

I actually abandoned this design in favor of a better design which I have not yet published. It needs an X-chain. 

V6

I really like the V6 on the mini.  It prints so well.  

Hopefully

Posted by: @djkirkendall

I actually abandoned this design in favor of a better design which I have not yet published. It needs an X-chain. 

Interesting to know , hopefully one day you may publish the print as Like most id prefer a more polished design if it’s possible 

Which print ?

Good to know which print did you use if you don’t mind me asking 

Posted by: @cwbullet

I really like the V6 on the mini.  It prints so well.