Hey, guys! I have an upcoming 3d printing project that requires gluing a lot of pieces of PLA together, So I want to know. What is the best glue for adhering PLA to itself? I’ve googled what’s the best. And what comes up is a glue called weld on 16 but I figured I should do some testing on my own to see how well it works compared to other glues. So let’s get right into it and see What’s the best glue for Poa. I’m gonna conduct two tests who have several different adhesives. I printed off a bunch of flat pieces of PLA for testing pieces like this and for the first test. I’m going to sand. The pieces of PLA for maximum surface area for the glues to adhere for the second test. I’m gonna leave the PLA pieces as it is with no sanding before applying the glues. I wipe down all the pieces of PLA with alcohol to remove any oils or grease that might have gotten on it from my hands also. This is really antidotal so ideally. I would use a measured way to test the strengths of the glues, but regardless, my testing should give me a decent idea of how well each glue will perform. So for the glues that I’m gonna test in no particular order contact cement, CA aka superglue weld, on 16 general purpose Goop, plastic model cement, polyurethane glue and Lastly epoxy. All right, so the glue is set up for a few days, and I’m ready to do some destructive testing. I’m going to first try to pull them apart. And if they hold up, I’m going to subject them to even more force by twisting them apart, so lets. Check out the results, alright? Contact cement, non sanded, so just by pulling its holding, lets. Try twisting [Music] so contact cement sanded so both the contact cement sand, it and unsanded held up very well. All right, here’s. Ca not sanded [Music]. Alright, see a sanded. So the CA held up really well for both standard and unsanded next up weld on 16 [Music] model cement. Very interesting, the model cement while it melted some of the PLA. It didn’t hold very well. That broke Super-easy unsanded model cement sanded [Music] again same result as the unsanded polyurethane. Whoa, that broke super-easy unsanded polyurethane sanded This one foamed up a bit too, because I added a little too much water to activate it. Same thing. Polyurethane aka Gorilla. Glue that broke really, really easy. Took almost very little force. Unsanded goop. That broke really easy. The glue just peels right off, sanded goop. [MUSIC] Same result as unsanded very easy and the GUP also just peels off readily epoxy unsanded [Music]. That just sheared off really easy. Epoxy sanded very similar result now. I don’t know if that’s the strength of the epoxy. But I’ve had really good luck with this epoxy for other things, okay. Wow, I was not expecting results like that. So all ranked worst to best based on my limited sample size of testing coming in at number seven polyurethane glue, I barely had to apply any pressure and the glue failed immediately, both sanded and unsanded pieces in the number six position. I would rate epoxy, not sure why, but I expected epoxy to perform better than it did. Usually epoxies are great glues for hearing most materials together so that was disappointing coming in in the number Five position. All-purpose glue, This glue actually held about the same as the plastic model cement, but it seemed to flex a bit and peeled off the PLA, so I’m giving it a lower ranking than the model cement. So that means coming in at number Four. Is the plastic model cement. This broke apart almost as easy as the goop, but it did melt the PLA a little bit, so I think it would hold a bit better than the goop. So far I would not use any of those glues for PLA as they all failed, catastrophic ly, with mostly clean breaks in the number three spot contact cement. This actually held up surprisingly well. I actually didn’t think this would be that strong, but it worked out really well with the PLA breaking the Florida glue In second place, I would rate CA superglue, slightly better than contact cement, but really, they were both about the same strength, and I really had to apply lots of pressure and twisting with the PLA braking first and not the glue, so that leaves in the number one spot weld on 16 This stuff here is really strong and actually melts. The POA informs a very solid bond between the POA pieces. I’ve used it on a few different projects, and it works on polycarbonate and acrylics too. So that’s nice. Honestly, though the top three glues all perform excellent with CA and contact cement really surprising me and epoxy and polyurethane really disappointing me. I thought they would actually do a lot better than that. All the PLA pieces were sanded equally for all the glues in my testing. I think my testing was sound, but the results of the epoxy and polyurethane bugged me. So I did some retesting, so I want to do an additional test with epoxy and polyurethane because those failed and I’ve had really good luck with those types of glues with other things. So I want to make sure to give them a fair shake, so I’ve printed off some rigid pieces of PLA sand at them very rough, and then I’m going to glue them one with PLA and the other one with epoxy just to test this one last time because with pieces of PLA like this that are thin and flexible, you can cause the glue to kind of fail by just kind of peeling it and it just it is just not as much like a structure for the glue to work with so. I think this would be one more test to give them a fair shake all right, next day epoch. See, let’s see how well this holds up, okay, that holds up really well, okay, with the coarser sanding and the more solid objects. This holds up super well like. I can’t break this. All right, polyurethane. These hold with a caveat as long as they’re sanded, really rough and the objects are more rigid as opposed to having a bit of flex to it. So that you can kind of peel it off the epoxy. The epoxy? Inge and polyurethane works very well, but it depends I better retest some of the questionable results, especially the plastic model cement. So ivory glued. This one, let’s see how well this holds up and I want to not bend it from out here because I get more leverage, but I’ll bended it here, and I’m just reusing this piece instead of having to reprint. Okay, so plastic model cement, not that strong. It looks like the glue. Kind of broke before the actual. I guess bond with the material because you can see here that on the white, it actually melted some of the PLA plastic model cement. Yeah, not that great and just for good measure. I reglued the poly and epoxy after sanding it with some really coarse sandpaper just to make sure to give this lots of surface area and a better chance of adhesion just to make sure kind of like how. I did on these blocks, so lets. Find out how these do. So here’s the epoxy, a little better. Okay, Well, the Pl April first. But it still looks like it’s separating a bit here, and I can kind of separate it with my hand, so I don’t know it’s not bad, but it’s not great, All right, polyurethane. Same thing, Reese and it with really coarse sandpaper okay again. I hit the camera, just cuz where my arm is, but this broke. I would say a lot better than the first time because the last time it just sheared right off this time, it’s significantly better, but as you can see well. I guess the glue broke before the actual bond with the POA, so not bad. But still, I’d say weld on 16 and CA would be the best and even contact cement. So I wanted to make sure to give all these a fair shake. My methodology might be a little flawed, But I don’t know post in the comment. What you guys, your experiences and share with the rest of the 3d printing world. Anyways, That’s what I found. The last thing to factor in is the top three glues also set very fast. So if you have parts that can’t be clamped, go with the weld on 16 CA or contact cement, so there you have it a very unscientific test of glues to use on PLA, so thanks so much for watching and subscribe to my channel for more esoteric videos like this. Also, if you subscribe to me for surfboard building, I have a few builds coming this year so really look forward to those and also be posting some travel videos from Southeast Asia soon too, so those will be kind of cool actually got a surf trip in on one of those as well. So that was kind of fun. Yeah, so that’s about it bye for now. [MUSIC].