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Hey guys,

after countless hours and multiple iterations, I would like to present to you the D-PATCH (Delta Printer with automatic tool changing). To my knowledge there is no Delta Printer available with tool-changing. I have been working on it for over 2 years (started in March 2018) and I am proud, that it is now a reality.

As you can see it’s not completely finished yet, because the actual tool changer is missing, but is in the making. A prototype is existing already.

Stats about the Printer:

Print volume: 300x300mm

Available tools: 5 (for now)

Board: Duet 2 Wifi + Duex 5

Power Supply: 24V 13A Meanwell

Security: Circuit breaker + RCD +Emergency Stop

Bed: milled aluminium bed with 600W mains heater switched with SSR

Print surface: Magnetic bed

Tool-Changing: Automatic and Manual

Control: PanelDue

I will updated the tread when I make more progress.

I'm really curious about your opinions and please let me know if you have any questions.

Adrian

Hey guys,

I worked on a tool length sensor which some of you may find convenient in certain circumstances.
e.g.

• nozzle change
• change of the hot-end
• tool changing

It is fully printable with some minor add ons which most of you have lying around. The Tool Length Senosr (TLS) can be wired in parallel to your z-probe (connecting between GND and IN), because its in fact a normally open microswitch.

I made a macro with conditional G-Code for it, which iterates through the defined number of tools. When the probe is hit by a clean cold nozzle (hot nozzle is possible as well with a small add-on) the current z position relative to the TLS is stored in G10 Commands and stored in the EEPROM (p.s. don't forget to add the needed command to your cofig.g).

;05.08.2020
M291 P"Please put Tool length sensor in the middle of the build plate and hit okay when done" R"Placing tool length sensor" S2
M291 P"ATTENTION: Machine is moving during the probing moves" R"ATTENTION" S2
G28 ; home
G90
G1 X0 Y0 ; move to center
G1 Z50 
while iterations<#tools		;run as often as number of tools
	if tools[iterations] != null	; check if tool is really asigned
		M291 P"Please put Tool" ^ iterationis ^ " into the effector and hit okay when done" R"Tool [iterations]" S2
		if sensors.gpIn[1].value=0	; check if tool is in effector
			M291 S0 T3 P"Tool in effector"
		else {}
			M291 S0 T3 P"Tool not in effector"
                        abort
		G91
		M98 P"Alarmsound.g"
		G30 Z-45 S-1 
		if  sensors.probes[0].value[0]>500
			G10 P{iterations} X0 Y0 Z{move.axes[2].userPosition-12.5}
			M500 P10
		G1 Z50 F500

If you have any questions or suggestions please feel free to ask

@oliof Yeah you are right - I found these videos, too, when I started to look into tool changing Delta printers, but not many infos out there.

About your question - yeah a little more brain juice went into the design of the locking mechanism.
So it is basically a bayonet lock that is driven by a Bowden cable and reset by a bunch of springs

The pieces of the bayonet that lock the tool are angled so a downward force is created by the rotation of the bayonet. It is locking onto 3 zylindrical pins that are placed 120° apart from each other so that the locking is uniformly

@JoergS5 Thank you
@jpomo10 of course ;). There are multiple options:

1. set the stand-by temperature so low, that a equilibrium is reached
   (+ no additional fans, - long heat up time)

2. one fan for each tool in parking position
   (+ sufficient cooling, - lot of fans with lots of noise)

3. one bigger fan with a fan-duct to direct the air to the heat sinks of the tools in parking position

For now I have no fans at all. So after the first prints I had not a lot of heat creep and no problems with jams. But I guess I will move on with option 3

BTW: I posted another video of the first dual color print on youtube

Hello guys,

I went a new way for the cooling of the tools without some parts of the sci fi attack hovercraft.
I added a fan to each tool instead. The data shows that the cooling is sufficient.

Hey guys,

as I have just 1 Fan output to spare I decided to make a small LED extension board which can control individual addressable LEDs (e.g. Ws2812) with just 1 PWM output from the Duet. This has several advantages.

Components:

• DC/DC converter (from 12/24V to 5V)
• Arduino Nano
• Screw terminals or pin headers

Advantages:

• LED modes (e.g. pulse, running LED, rainbow, ...)
• Just 1 PWM output needed
• With the DC/DC converter you have enough power for the Nano and the LEDs
• Nice integration in the macro system (just set the PWM of the Fan output in e.g. start g-code)

I will order some PCBs so when you are interested - let me know. When the files are final, I will publish them.

Here you can see some better pictures of the D-PATCH

As it showed up on the DWC I reworked the config and now it is there

So I guess all issues I had are now resolved.

Thank you all for your support!

Thanks that you like it! Yeah as soon as this version will be finished I'm thinking about publish the files under CC-BY-NC so that the community can use it

BTW: I really love your unconventional tripteron design!

Started working on the Tool-Changer itself

Tool Change Scripts

Hey guys,

I keep posting small videos - some are not really special but I still want to share them with you: https://youtu.be/6-CR_1vN3cE

In this small video I print with my go-to 100mm/s-profile

And I just uploaded a video of the change of 4 tools
https://youtu.be/aJt_HRal5rY

@jpomo10 Nice to see that others are thinking about options aswell.

To be honest these were my first attempts aswell. The first concept was magnets and the second one permanent-electromagnets after that, but after a lot of testing I decided not to use magnets.

@HebigT slow and steady

@PCR Sure if there is demand I will put all the files plus BOM on Github (or similar). The one you see is lets say the "maker" version where you need close to no custom parts.

At the moment I work on another version with some improvements (which can be easily implemented in the maker version)

@arhi @bearer
so I tried my luck with: move.axes[3].machinePosition but the addition did not work.

The use case is that at a certain point in a tool change macro the Z axis needs to be relative to the U axis (that's why I want to set the Position of the Z axis X mm (e.g. 30mm) from the U axis (because they have and have to have different homing positions).

So after your suggestions I tried G1 Z{move.axes[3].userPosition+30} and now it is perfectly working.

Thank you guys - you are the best!!!

@gloomyandy Wow so it seems that 3.2.2 did the trick ... now I get a stable connection - thank you
@jay_s_uk thank you! worked at least half needed to Bossa the 3.2.2 Duet2SBC firmware on the duet manually
@wilriker seems like the only problem left is, that the Duex is not recognized

Hey guys (more like @dc42 ),

are there plans to integrate remanent variables that keep their value even after a reboot/power out. That would be great as it would help integrate variables in the workflow.

Best Regards

@mrehorstdmd You need preload because than there is no backlash/tolerance in the guides. The kind of preload (light medium heavy) depends on your application. I use Z0 for my application and EG guides.

See Hiwin cataloge "Choosing preload Depends on the stiffness requirement and accuracy of mounting surface"
https://www.hiwin.com/pdf/linear_guideways.pdf

For Duet2 Wifi it happens that the Wifi Server FW gets corrupted and needs to be installed manually (e.g. via Pronterface). This happend to me multiple times from 3.0.0 onwards.

Hey,

so when you set the Z=0 Datum, it makes sence, that you can't move the printhead down by -9 mm because of the axis limits.
You may want to allow movement below 0 to accomplish that (But with Caution!!)

; Axis Limits
M208 Z-3 S1 ; set minimum Z

Best Regards
Adrian