would be intersting to know how much you loose in Y travel on the 2x4 when you install the tool rack. Thats the reason i went with 4x4 and my mdf base sheet is 51.75 x 41" currently
Ended up deciding to just go ahead and make the enclosure 48" tall.
Thereās absolutely no real need for it to be that tall, but I just canāt afford to have the machine down again for another enclosure upgrade because it needed to be biggerā¦ So bigger it is for me.
That said, Iād still say 41"ā43" provides plenty of room for anyone looking to build a shorter enclosure setup. My setup is just a bit more extreme because of the ducting, vacuum configuration, and the possibility of raising the machine again later on.
I also got around to putting together the 6-tool rack andā¦ as I suspected, it doesnāt fit my configuration with the fixture plates ā both in the X direction and in terms of the space underneath.
I didnāt get around to taking measurements yet, thatās tomorrowās job.
At this point, it looks like a custom solution is going to be the only way to make everything work properly. The good news is I should still be able to make it removable so I can retain the full functionality of gsender and the full cutting area when needed.
Most likely will have to also look at a retractable/auto detactable dustshoe designā¦
@Altmillal1114 I think the specified Y axis cutting goes to 20.3ā down from 25". Itās likely that my custom solution will also end up at the exact same remainder cutting area with the tool rack.
thats what they told me. Are you planning to do retracting rack or same as OEM?
just noticed in the picture, isnāt it suppose to be along Y axis on the back 2 crossmembers? this looks like its on the right side not the back. is that the spot you want to mount it in?
Very high chance here that Iāll stick with OEM style rack. Iām looking at the ports thatās available for mist coolant + retractable dust shoe. If there are extra ports to use, I might make a cover but thatāll have to be for later.
As for the picture, the Altmil 2x4 only has 3 crossmemebers, what you are looking at is the rack on the back 2 members but tucked to the right. Thatād be the spot where Iād want it to go. I believe itās also the spot that Sienci recommends for the single rack
ah now i see it. Yep. would be interesting to see what you come up with for mist and dust shoe
For anyone planning to get the ATC and use the Sienci 6-tool holder rack:
Youāll need to lift the machine by approximately 2 1/8".
- 1/2" aluminum block
- 2x4 (which is actualyl 1.5x3.5)
- 1/16 neoprene rubber x2
Otherwise, the tool rack sensor plug wonāt clear properly underneath the machine.
Also pulled all the critical dimensions for the ATC setup needed to design the custom rack and dust shoe system - including the ATC spindle itself and the OEM tool holder locations that Sienci Labs uses.
Seeing it laid out like this actually opens up the possibility of designing a custom tool rack directly on top of the fixture plate, since none of the tools we use have particularly long stick-outs.
In the OEM location, the distance between the bottom of the tool holder and the fixture plate sits at 38.69 mm. That can also be increased by another 5 mm, bringing total clearance to 43.69 mm (1.72").
The spacing between the tool holders also sits at 90 mm center-to-center, which appears to have been designed around the dust shoe that comes with the ATC.
A custom solution might be able to bring the spacing down to around 75 mm.
If that works, I could potentially fit all 6 tools onto a single fixture plate. Otherwise, I may turn this into a 10-tool system instead ā starting with 5 tools on one plate, then adding another 5-tool plate later if needed.
Weāll see where the measurements and clearances end up landing.
Oh manā¦went down a giant rabbit hole. Spent a bunch of time modeling this. I think Iām going to go with a 5 toolholder rack with standard Sienci spacing which is 90mm a part. It gives me the ability to make 2 of them and add a 2nd one when I need to. I did move the holder up by 5mm, but this is just optimizing at this point.
Iāve reached out to Sienci labs to see if I can get the actual tool rack clips STEP theyāve designed. For now Iāve just captured something to give me the critical dimensions for making the face plate.
I havent finalized the āfront plateā yet, but I might make it more of a shield, so the 4 notch down isnāt as low.
Below is how I plan to build the āhold downsā and fixture it onto the build plate. I might keep the ārack sensorā by putting it behind one of the hold downs by using 2 dowel pins for registration and quick removal when I need to remove the rack.
simulating a 35mm stickout on a 6mm endmill, still have 8.69mm of space.
With the spindle all the way up, I still get 121.92mm (5.19") of Z area cutting with 35mm stickout on the tool. minus any fixturing.
With the carriage all the way up front, The Y axis cuttable area on the stock OEM tool rack position 513.64mm (20.22") which is right around where Sienci Labs states their rack would reduce it to. with the fixture plate setup I could move the rack back by a fixture hole, which would give 31.75mm (1.25") extra space. in the Y. so I think if Iām really pushing for maximum cuttable space, itāll be somewhere around 21.5"
Onto the custom dustshoeā¦ I think I am going to go with Francis Creations AutoDust boot controller. As the documentation of the ATC from Sienci uses SWT1, SWT2, PWR1 aux ports, Iām left with Coolant + PWR2 to control mist coolant and the retraction of the dust shoe. Iām planning to use PWR2 on a 24V solenoid for the mist coolant. Alternatively.. I could get an IoT relay for the coolant port and a 110V solenoid to trigger the mist coolant and have the PWR2 port for the auto dust boot.
@siganberg, is it possible to use coolant port 5V , or use PWR2 for your Autodust boot controller? want to collaborate on this?
wow nice progress. Iām jelous and impressed with your fusion skills 
Ping Francis over on his discord, you might get fast response as he is pretty active there
Thanks Alex, it helps to be an industrial designer, and run businesses that use CAD on a day to day. It takes a while but youāll get there. I do most of my work in Solidworks, but Onshape is close enough so I use it for the odd thing here and there for personal projects. Fusion for CAM only, something about fusions CAD has me confused when it comes to their assembly/mating system.
good point about pinging Francis over on his discord, Iāll do that.
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Control signal for AutoDustBoot is 3.3v to 5v. Power supply is 12-24v.
I sent multiple emails to Sienci asking if they can provide or loan their ATC so I can both build an AutoDustBoot version for it and also develop a plugin for ncSender so users of Sienci ATC can use it in ncSender. I have been approached by users multiple times to support it, but purchasing one mostly for the community is not financially practical for me right now. Most of my products are really niche market and recouping investment is not really realistic as I still do this as a hobby. 
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Thanks for the control information. Iāll pickup a Autodustboot controller from you and design a version of a dust boot system of my own.
It makes sense too that a $4500 system is hard to justify development.
Iām happy to help out anyway should you want someone to collaborate with on your Sienci ATC product. Iām not here to make money off my creations on the Sienci platform, infact Iāve got nothing to sell lol. Just showcasing whatās possible should anyone feel they want to go down this route.
Had a friend help with getting the brackets and plate made while I was setting up the machine.
For those with a keen eye, donāt judge my cap screws in counter sunk holes, had to work with what I had at the time. Flat heads are on the way. 
The team over at Sienci has also been great on helping me get this unconventional setup done as well!
For anyone looking to setup their own custom tool rack. Here is the process to follow. (This process might change with software updates)
- Start setup wizard
- For Rack Size Pick 6/12 tool rack to setup
- apply the controller settings
- re home the machine
Up to this point, its all the standard setup
- for rack position pick manual
- Move the spindle directly over the taper (the menu will ask you to remove the pull studd, I did not) I centered and lowered the spindle so the tapers lined up. and left about 2mm gap.
below is the instructions by Sienci labs for this step
In the setup wizard, use "manual" to define the position of the left-most pull stud (i.e. Have the spindle taper directly on top and enveloping the first pull stud, then set that as the location of your rack. You may have to try it a few times if you don't get the height right the first time around since the spindle drawbar will push the tool holder out by 2mm from the locked position and if you set the pickup location too low, the forks may not be able to soak it up.
- After setup is complete, turn off the controller, remove the SD card and find the P100.macro in the root of the SD card.
- Open P100.macro and edit the field <_tc_slots> so that instead of 6 / 12 it equals to 5.
- Reinstall the SD card, restart the controller and re-home (ideally from outside of the rack area to prevent crashes).
- Try a tool change.
**Inside the P100.maco youāll also find other values to adjust such as the tool spacing, youāll find the default of 90 in there.
One of the other thing I had to adjust is the tool change keep out area when the rack is installed and the sensor is active. I have my TLS at a location that was in that keepout area but I didnāt find any reason for it in my setup for now (this might change after the dust boot is designed). So I had to adjust the Y axis keepout value so that the probing sequence would work otherwise I kept getting an error 2 soft limits hit.
Making a retractable ATC is not for the faint of heart but its definitely made easier with support from the Sienci team and Francis Creations with the Autodust boot controller.
The primary goal throughout the project was to keep the workflow as āstockā as possible. I wanted to avoid modifying the post processor wherever possible and minimize changes to the standard ATC macros. I pulled the necessary dimensions directly from the stock Sienci dust boot, reused the original thumb screws because I liked the look and functionality, and designed everything else around those constraints.
The Sienci team was incredibly helpful throughout the process, answering countless questions about macros, setup, and post processors. A+ support. The same goes for Francis
Mechanical Challenges
The biggest challenge was clearance.
The Sienci ATC spindle leaves very little room around the tool holder, spindle body, tool rack, and machine frame. The dust boot needed to clear:
- The tool rack during tool changes
- The top of the pull studs (which I raised by 5 mm)
- Both sides of the machine frame
- The retract path for the spindle during ATC operations
Getting all of those clearances correct took three to four design iterations and roughly two to three weeks of development.
The next challenge was the motion system itself.
The retract mechanism is cantilevered from the left side and only guided on the right side by a linear bearing. Any play in the original T8 lead screw and nut would translate into significant droop at the right side of the assembly. As the dust boot gained weight, gravity amplified the issue, causing alignment errors and occasional collisions during tool change retraction.
This isnāt a criticism of T8 lead screws, they work well for many applicationsā¦but for this particular setup the tolerances required were simply too tight.
To eliminate the majority of the backlash, I replaced the original system with a SKF 0802 ball screw. This dramatically improved rigidity and reduced the droop caused by motion system play.
Adjustability
One lesson any mechanical engineer types knows is that perfect CAD doesnāt always translate into perfect reality.
To compensate for real-world tolerances and deflection, I split the cross brace into two sections connected by an M8 clamping bolt. This allows rotational adjustment to compensate for any slight misalignment and delfection caused by weight or assembly variation.
I also introduced additional adjustability into the support arms that connect to the dust boot itself.
The result is a system that can now be independently adjusted in all three axes, making it possible to precisely dial in clearances for reliable tool changes.
Construction
All structural components were printed in PA6-CF.
Every threaded connection uses heat-set inserts for durability and repeatability.
An unexpected benefit of the redesign is modularity. The system can now accommodate larger lead screws, up to 10 mm diameter, a new accessory plate should anything change or I wanted to add more things. Homing trigger distance adjustment, 2,3, or 4 right side support linear bearings can all be changed out without requiring major redesign of the remaining components.
The lower dust boot section remains magnetically attached, allowing quick removal for inspection, maintenance, or manual tool changes.
I also integrated a mounting bracket for a mist coolant system. The nozzle assembly sits neatly out of the way whenever it is not in use.
Electronics and Controls
The Francis Creations AutoDust controller is connected to the SLB-EXT flood coolant outputs.
Connections are:
- 24 V power from PWR2
- 5 V signal from the flood output
- Common ground
The standard Sienci ATC macros already use M8 and M9 commands during tool changes. Since the AutoDust controller responds to those commands, the dust boot automatically deploys and retracts without requiring any modifications to the stock ATC workflow.
For mist coolant, the solenoid valve is connected to the PWR2 output on the SLB-EXT and controlled using:
- M64 P3 = Mist ON
- M65 P3 = Mist OFF
The M65 P3 codes needs to be added to a few macros, with M64 P3 added to the post processer, in this case itād only be in the fusion 360 side for me.
Edit: One thing to add is that this uses up all available easily accessible ports on the SLB-EXT. since the ATC uses up a bunch already with itās daughter board. The good thing is I donāt currently have anymore things I would like to add to the system and canāt imagine what those things might be. Time will tell.
oh man this is awesome progress. did you try Francisā ncsender?
I havenāt tried ncsender yet, mostly because I donāt think it supports Sienciās ATC setup and the macros required for everything to run correctly out of the box.
I think itās totally possible to copy the macros over and deploy them, but then theyād all have to run as macros instead of integrated UI elements on Gsenderās interface.
someone on the discord is working on the sienci atc plugin
sent you a DM couple of days ago
Hey Alex, sent a message back. Happy to help where I can.
It seems like there are a few people on here/fb group have have been looking for an retractable dustshoe system for the Sienci ATC.
Lol I feel like at some point Sienci should just built a motorized retraction system that triggers based on M8/M9 and the community can then build custom solutions on top. A fun thought excersize of what could be.