I didn't skip a second of this. This research is great. I've always took my nylon out of the vacuum seal and went straight into a 170 degree dryer for 4-6 hours and then right into a spool dryer and print through a bowden tube all the way to the nozzle. If you have a heated enclosure and your printers electronics are outside of it I recommend annealing inside the enclosure with the supports. From that point I'm thinking I should immediately cerakote and bake the nylon part right away. If I let the nylon filament sit for any amount of time in the atmosphere the layer strength went bad fast. Thanks for all the hard work. Increase the oil temperature to 212f or higher??
While I don't have a heated enclosure, I do anneal with supports, you just have to be carful not to break them off when removing the part from the bed.
@@HoffmanTactical Would it be better to increase support strength, and post-process to remove the connections? I've been experimenting with annealing Plaster of Paris compacted around the part. The downside to this is the toxic gasses the plaster releases. Any thoughts? I'm also considering a ceramic slurry used in lost ceramic casting to anneal my parts with. Completely encase the part in the ceramic slurry, heat in the oven and then remove the shell. A while back I'd asked you about a newer PVC filament that was on the market - have you had an opportunity to test it yet? I've seen good results, but I'm not sure how it would apply to this specific use case. I know you have to use brass nozzles, and there's a risk of chlorine gas with PVC, so printing in a well ventilated area would be a necessity. Not sure if it'd be worth the trouble. I'd also be VERY interested in seeing how well some blocks for stamping sheet metal lowers would work, if for no other reason than to reinforce the plastic with an epoxy. Ie a solid lower block to stamp out a sheet metal shell to encase a plastic lower.
Perhaps your results will be improved further if you used a polymerizing oil such as tung oil or linseed oil. After your print absorbs the oil it would harden and seal up the print preventing moisture from being absorbed into the print.
It’s 2023… get that thing cerakoted. A complete cerakote shell should block ALL moisture. That’s how we finish carbon fiber nylon parts for our customers, and it adds a personalized touch.
@@tenacioustinkerer7661Okay, but what if you are printing car sunroof mechanical parts? Will cerakote be helpful or a simple annealing is ok just it? Thank you.
You're doing so much good in furthering everyone's understanding of material science and how it relates to filaments. The technical side to filaments is so fun to nerd out on. Keep it up!
Would be super interested to see this test repeated with the parts soaked in a hydrophobic liquid like what can be applied to tents, outdoor furniture, etc. Great work, as always!
In wood working they use a heat activated resin. A popular brand in Cactusjuice. The wood is submerged in the resin then placed in a vacuum chamber. Sometimes it is cycled between vac and pressure. Once the wood stops bubbling it is removed and wrapped in foil. It is then heated to about 250F until the resin is cured. I wonder if a good wipe down of the exterior of a 3d printed part would maintain it's measurements. Another process is with Boiled Linseed Oil instead of resin. I allow BLO wood to air cure. I've never used heat cured resin.
I second the boiled linseed oil idea. I'm dubious about inpregnating petroleum based oil into plastic (maybe unfoundedly). Try annealing/inpregnating with a high smoke point vegetable oil.
Very interesting information! I really hope, YT doesn't nuke this channel. There's so much knowledge on here. Have you ever really tried ASA? I overlooked this material, because of needing a heated chamber to not warp too much. However it has very good mechanical properties. Impact resistence seems to be good, heat resistence is great, it has almost no creeping and is UV resistent.
I have used a little ASA, and a ton of ABS, all in the past. They are similar, ASA being more UV resistant. Both materials have good impact resistance, but poor tensile strength and layer adhesion. At least in my testing and experiences. I would almost always use a PC blend over ABS, though there are exceptions.
ASA does work but like Hoffman tactical said, not as strong/as good layer adhesions. PC blends use ASA or ABS in conjunction with PC to increase the tensile strength, might be worth looking into. Also polymaker makes a PC-ABS blend specifically.
@@HoffmanTactical Indeed. Just checked some test results, and ASA seems to have not so great layer adhesion (better than ABS though). However the ASA from eSun had pretty good results in the test by Igor from "My Tech Fun". Sadly availability in Germany seems to be bad for that one. But I will try the extrudr ASA soon.
Love the video. Looking forward to the next. Would love to see if there is some other substances which would impregnate the nylon (or at least provide a durable coating) to prevent moisture absorption.
Have you heard of stabilizing resin? I've seen it used to do basically the same thing for woodworking or arts & crafts. They use a pressure pot or vacuum chamber to remove air and replace with resin and then they cure the parts in an oven to harden it.
I was just thinking if you put it in cactus juice and then annealed it that the heat would anneal it and the cactus juice would stabilize it and that might be a good solution you beat me to it
I would love to see a clear lower using something like clear pctg / pc /xt, cnc kitchen has recently uploaded a video on how to get glass like quality from a fdm printer with thick walls. I think it would be a good idea to be able to show people where the wear spots are and you can even see internal stresses.
The pressured/forced impregnation is a great variable. My brain is in search mode for additional materials to test. Fundamental advancements in the materials first though, then incremental.
You should consider doing this in the microwave with carbon fiber filling. Carbon fiber filled materials can convert microwaves into heat, thus providing a convenient avenue for controlled heating.
Nahhhhh just get one that spins the food! Totally work! XD Actually I think what would be cool is an oversized receiver to see if it’s even possible to anneal it to proper spec.
here in dry colorado brittle zip ties are a real problem.... that i never had on the east coast..... Since the most strain occures during installation I soak them in warm water for a few minutes before installation. I'll go set up a storage test now... oil treated vs not, and check in a few months
15:16 Your explanation about oil being a competitive plasticizer (displacing water) makes sense, but I suspect that this trend could otherwise be due to differences in crystallinity (i.e. annealing degree-of-completion). Oil has higher thermal conductivity and higher specific heat than air, so it's possible that the samples in oil were slightly more crystalline, due to somewhat more effective annealing.
Vacuum drying may help. Vacuum annealing may help too. You can use a pressure cooker and a cheap vacuum pump. Vacuum may also allow more oil to be drawn in on those samples
You should try linseed oil, it’s a drying oil and used to season cast iron cookware to make a non-stick coating. The oil molecules dry to form a polymer. Extremely tough and slick. Maybe anneal in linseed oil, wipe “dry”, and let sit for a week or two before testing.
What do you think of using a hard watery paint or varnish that acts similarly to tung oil or boiled linseed oil? I think that the penetrating action would keep water out even with scratches and gauges, and the hardening action would maybe either increase wear resistance or strength/rigidity. There's this stuff called cactus juice which is used to stabilize wood and other natural materials, and has a curing temperature of 175-205, within the range of Nylons.
it's proprietary but most agree its some kinda glassfilled nylon.. probably a nylon12 Now good luck finding nylon12-gf.. its there but good luck. Also printing. nylons quite the pain to do right.
@@Shep01 well if I can find anything that can permanently bond to the frame like the structure epoxy I am using now I would definitely give it a try the stuff I am using now has been pretty durable so far and I am going to offer a beavertail stippling and Cerakote service soon
@@dependablekit5500 epoxy would definitely bond to a nylon frame(especially if you clean and roughed it up first). And for that area of the gun it would be very strong. Good luck.
The closes you’re gonna get is DuPont Zytel which is allegedly what Magpul Pmags are made of. It goes by the name CoexNylex Glass Filled Nylon these days. There hasn’t been any testing like has been done in this video, but in my “real world” applications, it holds up great. Feels like grip tape in your hand though but very strong and stiff
In addition to adding pressure, it would be interesting to see what "penetrating oils" like kroil oil would do. It may be possible to force something that dries/cures to be water resistant into the nylon, like certain wood finishes, after diluting with a solvent. .
Thanks for the tests! Some thoughts, Please test the PA12-CF with PA6-CF directly from Polymaker as well. It'll be a good and more direct 1:1 comparison and will help compound the fact that moisture affects nylon. Also, perhaps test a super strong nylon filament, such as atomic nuclear nylon with moisture as well. I know it hasn't the best layer adhesion, but it will be interesting to see how moisture affects a super stiff/strong nylon to begin with.
This has me wondering how the parts would hold up if coated in spray on silicone lubricant. Although slippery, it is remarkable in terms of waterproofing. For something like an AR lower where friction is largely irrelevant it could be a viable means of prolonging the effect of the aneeling.
@Hoffman Tactical 👉 It would be interesting to test coating test pieces with (a) Renaissance Wax; and (b) Turtle Wax 53409 Hybrid Solutions Ceramic Spray Coating.
Polymaker pla pro in terms of ease of use, mechanical properties, and price is a damn powerhouse. Yeah heat resistance is a problem but there are some remedies for that.
Have you looked into salt annelling(remelting) ? It's said to improve a part drastically. Would love to see if it would be better or worse than air or oil annelling.
Try using a pressure cooker as a vessel. Warm up the pan of the cooker with oil in it, then drop the parts in. Cap and hook up to an AC Vacuum pump. Vacuum down to .500 microns. then allow to go to atmospheric. Attach nitrogen source and pressure to cooker max. Leave for the time you want. Pressure cookers are handy for industrial uses.
Hoffman, a question for you: One of the key benefits on annealing is the layer adhesion increases dramatically. Have you seen or done any studies on that? I think post-anneal strength would be a big factor for print orientation.
I suspect the oil is only surface treating the nylon to create a water barrier. the heat and pressure annealing might force it in deeper but I dont see it working any better and might even make it weaker. it might be interesting to try the high temp and pressure annealing with light weight hydrocarbon gasses to see if new polymers are formed.
That was a suspicion of mine, but I did clean the oil off the surface of the samples before water absorption, and they appeared after the two weeks to be the same as the other samples, but for the odor of the oil. So I don't think it was a surface coating only.
Do you have a pdf or doc of this data and graphs for us to do some experiments ourselves and compare data? What was the humidity of the day? I live in a similar state and the humidity is similar. Would a dry room make a difference? Would you say your prints were exposed to sunlight while drying/absorbing? Would a different weight of oil make a difference you think?
There is a general misconception how the water absorption of nylon/polyamides works, that's why the oil idea failed. Nylon does not have "pores" that trap water, nylon chemically bonds with the hydrogen atoms of water molecules. So we look at many many magnitudes of size difference than what was expected to happen. The "oil annealing" likely only showed a wet-difference because the oil was still coating it partly, reducing water uptake so the "oil samples" were just more dry than their competitors at the time of testing. For the best strength of mechnical parts, you could try a laminating approach. Print nylon and another hydrophobic material in alternating layers. This sandwitches the nylon into the print making it almost impossible to absorb water in the projected lifetime of that part. The delay in printing should be acceptable, as the whole layer can be printed with one nozzle each time.
So basically what you're saying is this nylon blend with 8-10% CF rather than GF would be superior due to the added rigidity, better bridging, and better surface finish :P Some form of a thin clear coat of paint/epoxy seems to be the answer since from this baseline testing oil just isn't enough to get the rigidity of PLA+. I am curious to see the results of the PA12 CF nylon. Hopefully it's impact resistance isn't too low compared to pla+ or nylon 6 or 6/6 to be unusable. Impact resistance and layer adhesion are usually the points of failure with FDM printing in general.
you beat me too it, I was going to suggest trying the PA12. it would also be interesting to see polymaker CO PA. a couple thoughts on this setup....I'm no expert on nylons and moisture absorbsion, but I thought I read that the water that is absorbed forms a chemical bond with the nylon which acts as a plasticizer which is why the toughness seems to increase as moisture is absorbed. so when the term "absorbed" is used I guess the water is being chemically absorbed. I wonder how the oil is "absorbed" in the nylon. my guess is that it's mechanically coating the nylon and preventing water from being chemically absorbed of that makes any sense.... just hypothesizing here. another though is.... does the sample size (physical size of the sample) here matter? if you have a 1" thick slab of printed nylon, is the inside of that slab absorbing moistire? or are the few mm outside layers absorbing and protecting what is inside. maybe print a 1-2 mm sidewall thickness container, print and dry a sample, put inside the nylon box for a few weeks, see if moisture works it's way through the box or not? I would imagine a lot of cross sections of reviewers are thicker than your test sample, maybe the inner portions of thick members stay dry and stronger
thinking about linseed oil but then though what would be better than an oxygen activated resin would be a 2 part epoxy. put finished prints in the more liquidy/less viscus 2 part epoxy for an hour or two, then paint on the freshly mixxed 2 part expoxy, maybe with a drop of extra hardener if u have one of those types with the hardener catalyst seperate. just thinking, very good research and presentation.
Couldn't you theoretically do the same thing in a vacuum chamber? Wouldn't the moisture vaporize under vacuum and then the oil would absorb back into the pores once it returns to atmospheric pressure?
Thank you. Exceptional. Is the a place to donate? This work is more than a couple hardware kits worth. Confirmed my own informal observations without having to do do my own testing. I really feel I'm not going to get the properties I want, until I liquid cool my steppers, move most electronics outside the cabinet and go with PEEK printing. There just isn't anything in the lower heat ranges with the intersection of heat rejection, strength and toughness.
try annealing in Argon Atmosphere this is the proper gas for annealing Nylon.. do you have the temp increase Data and max temp hold times with decrease temp data?? first time seen some one trying to anneal Nylon correctly also sand support for complex shapes to help hold it's form works nice :) doing it in Argon rather then the oil preventing those pores and valleys from filling in, this is why the air one will be stronger at first these are getting filled in but there is still water in the air effecting the material as it exits those pores as well, also a lot of oils still absorb trace amounts of water soooo you might want to be aware of that (hygroscopic to a point before they start separating) any who if you don't have that data I should have it around here some whare
13:16 Having a small plastic deformation limit is not particularly a good thing because that means when it fails, it fails quickly. This means there is little to no warning before a catastrophic failure where as a material that has a greater ultimate to yield ratio will fail more safely.
We’re gonna need a chemist to figure out what kind of oil might actually improve things. I have a feeling the stuff is not likely to be safe to handle.
would be interesting to see what happens when you use a Heated Vacuum chamber to anneel the nylon in oil. i dont think pressure helps a lot to impregnate it. i would rather use a vacuum Nontheless, thanks for your tests :) great video!
Okay I’m actually incredibly stupid and can’t seem to follow anything in any video that Tim explains the technicals. He’s probably doing a fine job but like I said my brain can never keep up with graphs and such. I have multiple of Tim’s lowers printed out of Push Plastic CF Nylons. I’ve never annealed them. They have been sitting inside and rarely put any rounds through so far. #1 Would annealing them now do anything helpful or is it something you have to do immediately after printing? #2 is it bad if my nylon isn’t stored in a dry box but I always dry it hours before printing and seems to print beautifully if done that way. #3 is annealing 100% needed for my lowers.
Maybe I missed the detail, but did you do anything to the PLA pro with humidity or not? I don't think PLA is a sponge the way nylon is but I wonder if it would have a measurable effect.
Oil can degrade some plastics. I used to work in injection molding. One of the major quality concerns was lubricating oil, grease, or hydraulic oil leaking onto the chutes or conveyors that carried the molded parts out of the machines.
Has anyone tried using something like Cactus Juice (polymer) to eliminate water absorption? It's normally used to stabilize wood. Normally you put the dried material in a vacuum chamber with the cactus juice and then cure it in an oven at 220F.
Kind of makes me wonder what the results would be if you Treated printed nylon part with penetrating epoxy rather than oil? I am thinking about printing some parts for my boat, but worried about UV for PLA+ and moisure for Nylon.
These FDM fiber composites appear to me to put additional shear on the layer interface. Lots of tests on RU-vid verify tensile strength across layers, but what about bending loads? If you make a beam with the layers stacked vertically, each layer is inelastic and they'll try to slip against each other in shear. Like an indoor plywood left outdoors so the glue becomes weaker than the layers, bending the sheet will cause the layers to delaminate. A bent-till-broken Nylon-CF piece can actually look like broken plywood. The strong layers actually concentrate this shear into the layer interface. So I'm curious how a bending test would go for wet and dry nylon.
While injection molded nylon is “annealed by steam” to improve strength, 3dp community is trying to dry it in order to keep it brittle is interesting. Usage? Or layer adhesion issue?
Injection molded Nylon parts don't seem to have the same issues we do with water. It's interesting for sure. We are not keeping things "brittle", we are trying to keep them stiff. Less impact resistant for sure, but not fragile or brittle.
Okay, but does oil annealing actually improve the longevity of 3d printed parts? You should do a test where you take an already nylon printed oil annealed part and expose it to the Tennessee humidity over a week or so.
Want to test, do non polar solvents dissolve plastic, how much each plastic dissolves, is there a non polar solvent designed for and effective at not dissolving plastic? Thanks
My main issue with these types of test (and well most studies in general) is the lack of ability to eliminate or properly account for possible causes like UV light or the extra heat cycle degrading the material.
Yes, makes it tricky. However, I have not found small exposer to either of these to create any appreciable effect on material strength. Long term UV, certainly.
I have idé about anealing nylon for stronger parts i believe you will find highly interesting. On what platform can i get in touch with you to discuss it further?
Can you clear this up for me? Is moisture intrusion a problem with all plastics or just non homogeneous 3d printed parts? Furthermore, once a part is annealed, is it still susceptible to moisture? Lastly, would a simple coat of paint help this issue?
All Nylons of this type, even molded ones, suffer from the same issue. As the testing showed, annealing had little effect. Coating the part with a waterproof barrier should help.
@@HoffmanTactical Was me who suggested it on insta 😂🤙🏻 just on the wrong RU-vid account right now. Works excellently for tubee22 barrel, I can’t wait to see where you take the idea! Would love to get an SOT on board to test how silicate-impregnated suppressor baffles/housings hold up! If you already have a vacuum chamber for filament drying, I’d be interested in seeing difference in silicate penetration depth for atmospheric vs pressure too! Also, silane coupling agents are definitely worth looking into here, most commonly/easily found in “Automotive Adhesion Promoter”. Idea is to create covalent bond between plastic and glass in which the glass absorbs inside of the nylon fibers and permanently fuses together, meaning impacts that shatter the glass would only do-so contained *inside* of the nylon while the nylon retains shape and the coupling agent retains the covalent bond which keeps the glass particles fused to the plastic, resulting in significantly increased heat deflection and some added rigidity from the glass without sacrificing flexural-modulus/impact-resistance/elasticity properties of the nylon. Potentially could even allow-for printing unfilled nylon and more-or-less converting it to what essentially amounts to glass-fill during post-processing, which would alleviate layer-adhesion concerns with printing pre-filled glass filament. The only unknown variable would be particle grain size, but adaptive grain size depending on directions of applied forces during end-use might actually be of greater benefit, and grain size could be determined by just burning the print until all that’s left is glass and then contacting professors at a local college/university about transmission electron microscopy, which most will be happy to help you with for free if they have the equipment on hand.
Try linseed oil. It hardens as it is exposed to air. Be carfull though if you do. It generates heat as it reacts and hardens and might get hot enough to melt the part. also where the spontaneously combustion oily rag myth comes from.
Aye u forgot to say the area under the stress-strain curve is equal to the toughness, or energy required to break the material. I wonder if the wet nylons are actualy tougher somehow (the areas in ur graphs looked slightly larger).
Yes, and I also use my impact tester for toughness. While I've not tested the dry Nylons yet, I think it's safe to say that the wet Nylons will be much tougher. However, that does not matter if they are not stiff enough!
I have, though not done a lot of testing. It is similar to other higher fiber content CF Nylons. Strong, prints pretty good, but rough surface finish. The PA12-CF has a lot less fiber and a really nice finish.
@@HoffmanTactical I got a decent amount of PA6-CF for my own prints, and the rough surface finish is pretty obvious. Other than being slightly uncomfortable to hold, does a rough surface have any practical downside to its function as a part?
Wondering how much of a difference in test results there'd be for PA12CF? I sell brackets for the land surveying industry and have a current order for Puerto Rico, was wondering if annealing would help with the longevity of my parts, or just be a waste of valuable material testing things out.
@@HoffmanTactical Im concerned with reliability and rigidity than anything. I mean its layered plastic no matter what you do, its greatest strength is its greatest weakness.
I would doubt that the nylon is absorbing the oil like it does water. I think nylon absorbs water on a molecular level and if that’s true then the oil molecule would be to large to absorb into the nylon. I think that oil annealing in is just drying the nylon out a little and then coating it. If you could find a way to completely seal the nylon from water absorbing into it then I feel it would be a good material.
I'm not so sure, I cleaned the outside of the nylon off and it appeared to be just like the other nylon after that. If more time / pressure does not improve the results, then you may be right. We will see!
Humidity is realitive to temperature so a hot day at 30% might be more water than a cooler day at a lower temp. Also you need about twice as many samples before your stats really hold any actual weight. The smallest set should contain no less than 6. I know it's a pain but you'll actually get far clearer data. So the oil doesn't seem to actually degrade the plastic. Instead just isn't as strong an increase as much as letting it be dry. Those close numbers would be better if you used many more samples. However, it is still understandable why you wouldn't you've getting what it is. Send me a message if you need a statistical experiment designed is be more than happy to help you if that's something you need.
@@HoffmanTactical Ah, fair point. Thank you for the reply. I guess in my mind 3d printed firearms aren't meant to have a long service life. Once the process is perfected I see the receivers as being consumables. Ultimately the entire rifle is a tool that will wear out. The part about 3d printing that entices me is that you have the ability to replace the parts somewhat cheap and in a timely manner.
