no way, you made the captions fly into the screen correctly , finally ! it was the only thing that was bothering me throught your videos, keep up the good work man
I didn't really make the connection the first time around but IPA causes stress cracking in the polycarbonate housing and the threads would have been under stress. Always interesting to see it happen in practice. You can get them in PET but it can be a bit harder to find and might not be worth it for this. (Have always loved the 'bend a CD in half and it'll hold, dribble a few drops of IPA on it and it explodes/shatters as a demonstration. :)
I wish I had gone through all of your videos last week when I found your first one. I already ordered all the tubing and what not, and the original housings which have been delivered. Thankfully they are not expensive. Also, the next time you need to bend tubing like that there is a trick that is used when bending tubes that they use a silicon insert to keep the tubes from crimping. You could look into that for the next revision.
Yes I'm aware of the silicone insert method, but that would have been an extra thing to purchase my solution cost me nothing. Also I was concerned about removing the silicone insert considering the length of the tube and the tight radius.
Loved to see your problem solving flow unkinking the FEP tubing with hydro forming! The one change I would suggest to the system the next time you rebuild it, cut a piece of ply the size of the cabinet side and mount the whole system on that. Then you can work on it flat on your bench without gravity fighting you on your knees the whole time. I try to stay off the floor as much as possible these days. 😂 Keep the quality content coming!
Just what I was looking for! I had something similar set up for my salt water aquarium with the addition of dionizing cartridge which reduced the tds to 0. I've had luck using the aluminum sulfate additive solution to clarify the solution so I might want to try that this set up. I'll let you know how this all works out in a year from now. Cheers!
Next time you (re)install, you could put the entire system on the right side of the cart, that way the inlet of the pump will be closer to your form wash. Might also want to look into kink-free or reinforced silicone tubing to mitigate the tubing collapse. I am curious on how effective this expose and wash system is and whether it is primarily removing the photoinitators and keeping a bunch of the resin monomers still suspended in the solvent.
Do you have any feel for whether the UV light is actually curing anything? I was under the impression that the photo-initiators in the resins had to be of a sufficient concentration to actually catalyze the polymerization, and so when the resin is diluted in IPA the resin could not longer cure, even if exposed to intense UV. If this is true, I would think that the only things getting filtered out of the IPA are the small cured particles washed off the print and any pigment particles used to color the resin, but that the majority of the pre-polymers would still be in solution.
That's a very good question, I'm not a chemist so I'm not sure about that, it's difficult to say whether the UV is curing it I would think however that some of that is occurring because when you take IPA and you put it out in the sunlight the resin does coagulate, and ultimately that's what I'm trying to do with this system is get the resin to coagulate or thicken up so that it can get stuck in the filter.
Ideally, it would be nice if there was something that you could add to the IPA to help coagulate the resin and basically thicken it up and get trapped in the filters.
In theory the resin will get cured eventually and filtered out, that's the idea. At this point with the system as it is the IPA doesn't get too diluted with the resin as a certain amount gets filtered out and the IPA is always usable to clean your parts.
The "UV loop reactor" is a geek marvel. But the surprise effect having passed, I wonder like some others if the diluted resin in the moving contaminated IPA has really the time to cure and precipitate as bigger chunks in it. A comparison of the filtration from a muddy IPA bucket with and without the loop reactor would be very useful. If this item is not really useful in the filtration process, it will make the setup much simpler and more affordable. One has to find out.
Theory instead of experiment for now. Let's say the 5-meter UV LED strip wrapped as a coil around the tubing has 600 LEDs and consumes about 40W power total. This is a very good light strip (they are often half as good). The UV loop reactor is made of 5 meters of PTFE/FEP or silicone tubing, whose ID is 1/2". It's a bit less actually, because you have to connect some tubing outside of the reactor to the pump outlet and to the filter housing inlet. But from this approximation, I made a rough calculation (MKSA units): Say the pump is capable of moving the liquid at 15 liters/min, i.e. 0.25 liter/sec - I think it is less in reality, but sellers advertise an even higher volumetric flow rate. Using these numbers, do you know how long a particle of resin flowing within the IPA along the tubing stays inside the UV loop reactor? About 2.5 seconds. If the actual flow rate of the pump is lower, say only 10 litres/min, the actual transit time of the resin in the UV reactor is 4 sec. However, if the real flow rate of the pump is 20 liters/min, then the resin stays in the reactor for 2 sec only! Now, imagine powering your Wash & Cure (the curing part) for between 2 and 4 seconds in order to cure a 3D printed object, and what's more that this object is immersed in a container full of IPA, which has the primary function of wiping resin. Do you think that the surface of this 3D-printed object would cure in such conditions? I don't think so. EDIT: it's even worse thant that, because 10' = 3 meters, not 5 meters. So the estimated transit times are in fact 40% less thant what I said above. We are in the order of 1 to 2.5 sec.
I Assume the resin gets cured after about 10 times thought the ring at that rate. Seems reasonable that it will take a few times through to get the job done. I'm also assuming that the combination of the UV and the filter working together filters out most of the resin. I don't think it all actually gets filtered out I don't think that's possible. I think I'm just trying to reduce the amount of resin in there so that it's still effective at cleaning the parts. I'm good with that. The main thing is I don't have to mess with the IPA.
@@EricStrebel Your recirculation remark is valid I think. I'm currently in the process of deciding whether to build this setup with or without the UV reactor part, and I'm trying to get a clearer picture and weigh up the pros and cons. I haven't settled yet.
On some models of those pumps that you can rotate the pumping head 180° to change the direction of the inlet and outlet. Something to try out. As for the charcoal filter, I don't think it will contaminate the IPA, however I'm not sure about the benefit. It's usually used to prevent water from getting weird tastes, it's not exactly a mechanical filter rather a chemical one.
Usually, photocurable resin must be in a static state when curing. The photoinitiator in the resin absorbs ultraviolet light and generates free radicals, which combine with oligomers and monomers to form a three-dimensional network structure. The premise is that the resin must be in a static state when curing. Only in this state can free radicals and other substances in the resin be stably polymerized, so that the resin components in the isopropyl alcohol can be polymerized together as much as possible to increase the purity of the filtered isopropyl alcohol. In the video, a UV light strip is attached to the pipeline, which may not take the time required for the resin to cure. Moreover, the resin in isopropyl alcohol is in a fluid state, and free radicals cannot polymerize stably. Some components in the resin are separated. Very small, if it is not polymerized with free radicals, it will still flow out of the filter along with the isopropyl alcohol.
So from your point of view, this set of equipment doesn't really do much of value, does it? Even if the IPA in the drum is cycled through multiple times, the resin content of it is essentially not reduced, or only a very small percentage is actually filtered, is it?
Hi Eric, do you (or anyone else reading this) have any thoughts on using this kind of setup with methylated spirits/denatured alcohol instead of IPA? I've been using that as it's much more affordable here but I'm wondering whether I should be worried about temperatures/flammability.
Because IPA is highly flammable (especially the IPA vapors that can explode with a flame, spark, or even just temperature) I would eagerly suggest to cover the bucket of recycling polluted IPA with an airtight cap, because I don't think that this kind of cheap electric water pump nearby is properly isolated, or in any case antistatic and anti-explosion rated. Moreover, on a more practical side, an airtight cap would also prevent the IPA from degrading too fast (because IPA is expensive, absorbs moisture, and evaporates quickly).
I assume that your filter housings that cracked are polycarbonate. I worked for a medical device company and we solvent bonded polycarbonate pieces together. In order to help polycarbonate resist cracking when bonded we would "anneal" the parts it about 200 degrees F for several hours before bonding. It help eliminate the fracturing of the resin. I have actually seen polycarbonate almost blow up if not annealed. Ditto with 70% isopropanol.
You see that crazy and cracking on Old polycarbonate parts all the time, and sometimes it's just from being cleaned with a solvent people don't know particularly on cut edges like from a laser or something that's machined.
After having run this system for several weeks are you able to comment on the longevity of the filters and the effectiveness of the alcohol for cleaning? Some other recycling methods noted the alcohol became “slimy” after a while and was leaving residue behind on the parts even though it looked clear.
My experience with essentially this exact device resulted in precisely that sort of issue. After running a good number of kilos of resin through, I still had clear looking IPA -- but it left an increasingly gross, sticky residue on prints that went through it Ultimately, I gave up on the device for these reasons, but I would love to find some revisions that solve the issue
Sounds like you had several kilos of useful wash cycles before it was junk, right? I'm weighing costs and wondering if this setup is worth saving $40 on IPA every few months
How has this held up for you? I'm curious about the IPAs lifespan. Some people have reported the IPA becomes a sticky, mushy sludge after several kilos of prints
I'm getting ready to build this - I use a and Elegoo wash station, which has a bucket and lid system. What would be your thoughts on drilling and adding some fittings to the bucket a bottom dirty hose fitting and a higher return for clean. This way the lid can be placed on the unit while running vs being open to the air? I'm new to all this, no idea how to add a hose port without leaks, drilling a hole in the bucket I got, lol
Hey I’m following this system from you and the other guy that you mentioned because I’m dealing with the same issue with my ipa, I have a question or a recommendation the tube coil makes any difference is you do more o less loops or the diameter of the loops matter because I’m planning to put it into a printed chamber to keeps the uv light inside the chamber
I was wondering if you could set up the system to pull the IPA through the filters rather than push it through. Then, if you lift the intake hose out of the tank and pull the IPA from the filters, you could remove the housing without wasting a lot of IPA. As an engineer, would that setup work?
@@EricStrebel I was thinking about using PVC and the silicone tubing you showed. Maybe having short runs of the silicone to go into the fromwash and pvc running into the filters and then from the pump back to the silicone. I have 2 fromwash units side by side so the silicine tubing could run to one or the other, but the pump and filters would be wall mounted. Just a thought on how your idea could be adapted to what I have. Thanks for the great videos and the links to the products. It's really an inspiration.
You are more of an "industrial engineer". Our profession should better differentiate "designer" with "engineer". Designers are typically aesthetics driven in the Form Follows Function Model. You are more on the problem solving side of Industrial Design. As someone with 35years in the trenches good work here. Keep the vids coming!
Follow up question. has anyone experienced any issues with the resin sediment causing issues to the pump since it is the first device in the loop? I understand it was done to pressurize the lines to keep them from collapsing, but I am a little concerned about pulling unfiltered resin through it.
no way, you made the captions fly into the screen correctly , finally ! it was the only thing that was bothering me throught your videos, keep up the good work man
Ha!
I didn't really make the connection the first time around but IPA causes stress cracking in the polycarbonate housing and the threads would have been under stress. Always interesting to see it happen in practice. You can get them in PET but it can be a bit harder to find and might not be worth it for this.
(Have always loved the 'bend a CD in half and it'll hold, dribble a few drops of IPA on it and it explodes/shatters as a demonstration. :)
I wish I had gone through all of your videos last week when I found your first one. I already ordered all the tubing and what not, and the original housings which have been delivered. Thankfully they are not expensive. Also, the next time you need to bend tubing like that there is a trick that is used when bending tubes that they use a silicon insert to keep the tubes from crimping. You could look into that for the next revision.
Yes I'm aware of the silicone insert method, but that would have been an extra thing to purchase my solution cost me nothing. Also I was concerned about removing the silicone insert considering the length of the tube and the tight radius.
Loved to see your problem solving flow unkinking the FEP tubing with hydro forming!
The one change I would suggest to the system the next time you rebuild it, cut a piece of ply the size of the cabinet side and mount the whole system on that. Then you can work on it flat on your bench without gravity fighting you on your knees the whole time. I try to stay off the floor as much as possible these days. 😂 Keep the quality content coming!
Have you found your ipa is still cloudy after this? And theres build up in the loop of cured resin goop
Just what I was looking for! I had something similar set up for my salt water aquarium with the addition of dionizing cartridge which reduced the tds to 0. I've had luck using the aluminum sulfate additive solution to clarify the solution so I might want to try that this set up. I'll let you know how this all works out in a year from now. Cheers!
Cool. I have some I just have not tried it yet
Next time you (re)install, you could put the entire system on the right side of the cart, that way the inlet of the pump will be closer to your form wash. Might also want to look into kink-free or reinforced silicone tubing to mitigate the tubing collapse. I am curious on how effective this expose and wash system is and whether it is primarily removing the photoinitators and keeping a bunch of the resin monomers still suspended in the solvent.
Do you have any feel for whether the UV light is actually curing anything? I was under the impression that the photo-initiators in the resins had to be of a sufficient concentration to actually catalyze the polymerization, and so when the resin is diluted in IPA the resin could not longer cure, even if exposed to intense UV. If this is true, I would think that the only things getting filtered out of the IPA are the small cured particles washed off the print and any pigment particles used to color the resin, but that the majority of the pre-polymers would still be in solution.
That's a very good question, I'm not a chemist so I'm not sure about that, it's difficult to say whether the UV is curing it I would think however that some of that is occurring because when you take IPA and you put it out in the sunlight the resin does coagulate, and ultimately that's what I'm trying to do with this system is get the resin to coagulate or thicken up so that it can get stuck in the filter.
Ideally, it would be nice if there was something that you could add to the IPA to help coagulate the resin and basically thicken it up and get trapped in the filters.
That could be done in the actual form wash tank in between washes. Sometimes nothing gets washed in that tank for days or even a week.
Seems like a liquid pool drop out flocculant works for this. I am going to try this. Thanks for the tip!
In theory the resin will get cured eventually and filtered out, that's the idea. At this point with the system as it is the IPA doesn't get too diluted with the resin as a certain amount gets filtered out and the IPA is always usable to clean your parts.
The "UV loop reactor" is a geek marvel. But the surprise effect having passed, I wonder like some others if the diluted resin in the moving contaminated IPA has really the time to cure and precipitate as bigger chunks in it. A comparison of the filtration from a muddy IPA bucket with and without the loop reactor would be very useful. If this item is not really useful in the filtration process, it will make the setup much simpler and more affordable. One has to find out.
Theory instead of experiment for now.
Let's say the 5-meter UV LED strip wrapped as a coil around the tubing has 600 LEDs and consumes about 40W power total. This is a very good light strip (they are often half as good).
The UV loop reactor is made of 5 meters of PTFE/FEP or silicone tubing, whose ID is 1/2". It's a bit less actually, because you have to connect some tubing outside of the reactor to the pump outlet and to the filter housing inlet. But from this approximation, I made a rough calculation (MKSA units):
Say the pump is capable of moving the liquid at 15 liters/min, i.e. 0.25 liter/sec - I think it is less in reality, but sellers advertise an even higher volumetric flow rate.
Using these numbers, do you know how long a particle of resin flowing within the IPA along the tubing stays inside the UV loop reactor?
About 2.5 seconds.
If the actual flow rate of the pump is lower, say only 10 litres/min, the actual transit time of the resin in the UV reactor is 4 sec.
However, if the real flow rate of the pump is 20 liters/min, then the resin stays in the reactor for 2 sec only!
Now, imagine powering your Wash & Cure (the curing part) for between 2 and 4 seconds in order to cure a 3D printed object, and what's more that this object is immersed in a container full of IPA, which has the primary function of wiping resin.
Do you think that the surface of this 3D-printed object would cure in such conditions? I don't think so.
EDIT: it's even worse thant that, because 10' = 3 meters, not 5 meters. So the estimated transit times are in fact 40% less thant what I said above. We are in the order of 1 to 2.5 sec.
I Assume the resin gets cured after about 10 times thought the ring at that rate. Seems reasonable that it will take a few times through to get the job done. I'm also assuming that the combination of the UV and the filter working together filters out most of the resin. I don't think it all actually gets filtered out I don't think that's possible. I think I'm just trying to reduce the amount of resin in there so that it's still effective at cleaning the parts. I'm good with that. The main thing is I don't have to mess with the IPA.
@@EricStrebel Your recirculation remark is valid I think. I'm currently in the process of deciding whether to build this setup with or without the UV reactor part, and I'm trying to get a clearer picture and weigh up the pros and cons. I haven't settled yet.
@@fluxcapacitor I feel like it can't hurt, that's why I added it. Even if it has minimal functionality it still has some benefit and is worth it.
@@EricStrebel I will add it to mine. The geek wow factor had me.
On some models of those pumps that you can rotate the pumping head 180° to change the direction of the inlet and outlet. Something to try out.
As for the charcoal filter, I don't think it will contaminate the IPA, however I'm not sure about the benefit. It's usually used to prevent water from getting weird tastes, it's not exactly a mechanical filter rather a chemical one.
Usually, photocurable resin must be in a static state when curing. The photoinitiator in the resin absorbs ultraviolet light and generates free radicals, which combine with oligomers and monomers to form a three-dimensional network structure. The premise is that the resin must be in a static state when curing. Only in this state can free radicals and other substances in the resin be stably polymerized, so that the resin components in the isopropyl alcohol can be polymerized together as much as possible to increase the purity of the filtered isopropyl alcohol. In the video, a UV light strip is attached to the pipeline, which may not take the time required for the resin to cure. Moreover, the resin in isopropyl alcohol is in a fluid state, and free radicals cannot polymerize stably. Some components in the resin are separated. Very small, if it is not polymerized with free radicals, it will still flow out of the filter along with the isopropyl alcohol.
So from your point of view, this set of equipment doesn't really do much of value, does it? Even if the IPA in the drum is cycled through multiple times, the resin content of it is essentially not reduced, or only a very small percentage is actually filtered, is it?
Hi Eric, do you (or anyone else reading this) have any thoughts on using this kind of setup with methylated spirits/denatured alcohol instead of IPA? I've been using that as it's much more affordable here but I'm wondering whether I should be worried about temperatures/flammability.
Because IPA is highly flammable (especially the IPA vapors that can explode with a flame, spark, or even just temperature) I would eagerly suggest to cover the bucket of recycling polluted IPA with an airtight cap, because I don't think that this kind of cheap electric water pump nearby is properly isolated, or in any case antistatic and anti-explosion rated. Moreover, on a more practical side, an airtight cap would also prevent the IPA from degrading too fast (because IPA is expensive, absorbs moisture, and evaporates quickly).
Great video. Clever solution on the pressure forming. Mahalo for sharing! ❤️🙏🙂
I assume that your filter housings that cracked are polycarbonate. I worked for a medical device company and we solvent bonded polycarbonate pieces together. In order to help polycarbonate resist cracking when bonded we would "anneal" the parts it about 200 degrees F for several hours before bonding. It help eliminate the fracturing of the resin. I have actually seen polycarbonate almost blow up if not annealed. Ditto with 70% isopropanol.
You see that crazy and cracking on Old polycarbonate parts all the time, and sometimes it's just from being cleaned with a solvent people don't know particularly on cut edges like from a laser or something that's machined.
What is strange is that the plastic bucket of Wash & Cure machines (especially made to work with IPA) is made of PC.
@@EricStrebel Yes. My brother in law used IPA to try to clean off the price tag on a PC cutting board. It cracked immediately and pretty violently.
After having run this system for several weeks are you able to comment on the longevity of the filters and the effectiveness of the alcohol for cleaning? Some other recycling methods noted the alcohol became “slimy” after a while and was leaving residue behind on the parts even though it looked clear.
I will know more when I change the filters in the future.
My experience with essentially this exact device resulted in precisely that sort of issue. After running a good number of kilos of resin through, I still had clear looking IPA -- but it left an increasingly gross, sticky residue on prints that went through it
Ultimately, I gave up on the device for these reasons, but I would love to find some revisions that solve the issue
Sounds like you had several kilos of useful wash cycles before it was junk, right? I'm weighing costs and wondering if this setup is worth saving $40 on IPA every few months
How has this held up for you? I'm curious about the IPAs lifespan. Some people have reported the IPA becomes a sticky, mushy sludge after several kilos of prints
Decent, I am pleased, mainly because I don't have to do much
I'm getting ready to build this -
I use a and Elegoo wash station, which has a bucket and lid system. What would be your thoughts on drilling and adding some fittings to the bucket a bottom dirty hose fitting and a higher return for clean. This way the lid can be placed on the unit while running vs being open to the air?
I'm new to all this, no idea how to add a hose port without leaks, drilling a hole in the bucket I got, lol
Your solution is ideal if you can seal the bucket
Hey I’m following this system from you and the other guy that you mentioned because I’m dealing with the same issue with my ipa, I have a question or a recommendation the tube coil makes any difference is you do more o less loops or the diameter of the loops matter because I’m planning to put it into a printed chamber to keeps the uv light inside the chamber
Yeah, sounds reasonable
have you been able to determine if the UV loop actually helps?
How do the filters hold up to the IPA? Do you need a chemical filter to prevent the IPA from eating the filters?
Nope, have not seen a need for that
I was wondering if you could set up the system to pull the IPA through the filters rather than push it through. Then, if you lift the intake hose out of the tank and pull the IPA from the filters, you could remove the housing without wasting a lot of IPA. As an engineer, would that setup work?
In theory yes if you have the right tubing to support that.
@@EricStrebel I was thinking about using PVC and the silicone tubing you showed. Maybe having short runs of the silicone to go into the fromwash and pvc running into the filters and then from the pump back to the silicone. I have 2 fromwash units side by side so the silicine tubing could run to one or the other, but the pump and filters would be wall mounted. Just a thought on how your idea could be adapted to what I have. Thanks for the great videos and the links to the products. It's really an inspiration.
In theory yes, the only way to test it is to try it
You are more of an "industrial engineer". Our profession should better differentiate "designer" with "engineer". Designers are typically aesthetics driven in the Form Follows Function Model. You are more on the problem solving side of Industrial Design. As someone with 35years in the trenches good work here. Keep the vids coming!
Definitely a problem solver, not so much an engineer, but I do like building equipment for the process of designing things.
can you share the 3D files for the hose holder in the form 3?
Follow up question. has anyone experienced any issues with the resin sediment causing issues to the pump since it is the first device in the loop? I understand it was done to pressurize the lines to keep them from collapsing, but I am a little concerned about pulling unfiltered resin through it.
No issues onu emd
I think I would have hard-piped some of it.
So this has nothing to do with beer?
Молодцом!
Off to watch the first video, so I don't make an inappropriate India Pale Ale comment.
There's a link to the silicon mat, but there's no way to purchase.
At the bottom of the page is “add to cart” 😀 I will move the button up a bit, but you should be able to make the purchase!
IPA is more commonly an abbreviation for Indian Pale Ale rather than Isopropyl Alcohol.
Ahhhh, got the joke now. Funny
Were you #57 in the last Mr. Beast video or do you just happen to look just like him?