After some pestering of Formlabs, I finally received the proper 3L wash stations (versus the veggie baskets). Fit and finish could use some improvements, but what was more intriguing to me was the two nuts with flanges tack welded to the bottom. After playing with my bolt kit, I found out they are M3 threads.
I’m looking at taking advantage of these threads to put an air stone aeration system to agitate the IPA against the platform parts. Has anybody done something similar or does anybody have any ideas of what do with the two holes to make our own automated wash station?
@leonhart88 - That is ingenious. I wish I had done that with my bucket as well and I’m impressed by how much agitation you get from it. Very cool.
The entire design of the unit is a little baffling to me. The shape is wonky, but it’s as if it’s designed to fit into another housing (say a Form3L wash station?). The sides where the platform can hang from the handles are not symmetric and the right side at the hinge has a deepened notch with no explanation as to why it’s there. Good for us I guess since it’ll give us some creativity to put something in there (say an autofill pump w/ level switch?)
Unless you are using an inert gas for the bubbler system I would not do that. You will be pumping oxygen thru a highly concentrated alcohol. In my mind that is a fire waiting to happen. You should consider a ultrasonic mixer or a spinning agitator.
I agree with @nobermiller, but for another reason. IPA is highly hygroscopic, which basically means that it absorbs a lot of water. By pumping air through the alcohol, you basically inject the water vapor contained in the air into the alcohol. IPA is “infinitely” hygroscopic, thus it would eventually reduce its concentration to near zero, which heavily reduces its cleaning effectiveness.
Interesting, thanks to both of you for those insightful comments, I didn’t know either of those facts.
For others who are curious, a quick Google search and look at MSDS sheets shows that when IPA is mixed with air or oxygen over a period of time, can product unstable peroxides which can explode.
I’ve also noticed (anecdotally) that my IPA doesn’t seem to clean very well even though there is substantial agitation, so the hygroscopic nature might be at play here (although hard to tell without doing any quantitative measurements).
I’ll stop using the air bubbler then and just stick to the magnetic mixer!
After several months of trial and error (lots of error), we’ve found a MVP solution for the large 3L wash stations that is semi-automated. After a teardown of the small F3 wash station, we discovered that the system is simply a mag drive with a winged magnetic paddle tied to a stepper motor in the base, with a “inside tub” matching magnetic mixer blade.
We replicated this design using the two stubs inside the basin, which are clearly for these types of attachments and as I alluded to in prior posts, this basin is most certainly used in the formal 3L wash station. We 3D printed via the F3 printers or via a FDM printer all the pieces to make it work and after an obscene amount of dev time, we have a pretty reliable solution. Not very pretty, but it does agitate the IPA and wash our prints very effectively.
All the parts and pieces cost us about $250-400 dollars which is a far cry from the $3K automated solution, but it works and I’m happy with it. I’m more than willing to share the design with everyone as long as you don’t try and commercialize it for your own benefit. There are a lot of improvements to be made and I’m hoping the people on this forum would take this base design and help improve it for all of us. If anyone knows any arduino programming, it would make it extra sweet with an integrated timer and beeper to know when it’s done with the wash.
The interior mixers and the bottom paddle attached to the stepper motor shaft are made with high temp resin. It’s fairly immune to IPA after it’s full cure cycle, but the stepper motor gets crazy hot and it’s the only resin that we’ve tried short of machining aluminum that holds up to the heat.
All other parts that help properly locate the resin tank over the stepper motor were all FDM on a Prusa.
We currently have two of these wash stations as a dirty/clean station because we primarily use T2000 and they both sit on one cart that has two rectangular holes cut out for the stepper motor assembly. Apparently it’s a bit too much weight for the cart and our next immediate improvement will be to place the bottom into a vented enclosure to have it sit on a table.
Take a look at the pictures and lets crowdsource an alternative to the long delayed F3L wash station!! First ping me with your interest and then we can step this forward by sharing the files.
Cool nice work! Amy reason why you used steppers instead of just a DC motor?
I ended up actually just buying some cheap magnetic stirrers and dropping three magnetic capsules into the V1 wash buckets with great success after learning about the issues with bubbling air into IPA. I also sourced a better basket for the inside of the food tray.
I’m actually preferring that setup to the new V2 wash right now, but eventually plan to use the V2 as my second wash with a similar setup. The only issue is those welded studs are the bottom are actually kind of in the way.
Thanks @leonhart88. We took full advantage of those V2 wash studs as part of how we anchor down the internal stirrers. We went with a DC motor because there are definitely limitations as to what speed we can use the internal stirrers without breaking loose the stirrers from their magnetic buddy below the tank. In plain air, they work just fine, but stick 10+ gallons of IPA in the mix and there is a lot more drag on the mixer.
We literally use a start/stop method right now, which limits how fast we can run the stirrer. It’s that instantaneous startup speed which can break the stirrer loose, but a slow gradual startup (like on the normal F3 wash stations) allows us to go to much higher agitation speeds.
We did look at magnetic stirrers in the V2 basin, but the V2 basin is make with some crazy soft aluminum and it was starting to rub away some of the base aluminum material after a few hours of operation.
