Easier Fiber-Reinforced Resin Printing! Stronger and Conductive Resin Prints?

[@integza]

I love this kind of experimenting! Also you need to try ceramic resin

[@aidanvillacampa4745]

Integza, have you tried encasing ceramic resin in sand while kilning it to keep heat equal throughout the part and reduce warp? I have done that with other materials...

[@dagameface8181]

THAT TURBO JET WAS SO COOL~!! cant wait to see the v2, soon people are gonna make homemade jet aircraft lol

[@arnaudcochin3854]

Try to hammer some tomatoes with your shock device.

[@josephgauthier5018]

hmmm, i wonder why you want him to test ceramic resin in particular, lol.

[@aidanvillacampa4745]

@@josephgauthier5018 to make a more powerful engine of course!

[@nixhound]

The graphite bubble color is "structural coloration". Unlike a prism, where white light splits due to changing speed between mediums, here the size of the particles is comparable to the wavelength of light and parallel rays will constructively or destructively interfere causing the light to split. It is like a diffraction grating you might have played around with or a grating wavelength selector in spectroscopy.

[@42436freak]

1. Excellent and accurate explanation. 2. Your last name is perfect, especially with the high VanderWaal forces at play in graphite.

[@nixhound]

@@42436freak all my chemistry professors got a kick out of it too

[@whiterabbit47]

This physicist is glad someone posted a better explanation than because bubbles

[@Dalenthas]

I think Steve Mould did a video on this recently...

[@dejayrezme8617]

Is there an explanation of how there seems to be a kind of orientation going on? e.g. 6:45. When mixing different parts of the resin they seem to have a state or common orientation. Or is that just different settling of particles?

[@sirayatech2]

Great video. Since inconsistent curing from settlements can weaken a print, we recommend using a thicker, tough resin as the base for this type of experiment. This way, the materials do not settle too quickly, and you have a very strong resin to start to stay functional. Happy to get you some Blu or Tenacious to play.

[@globalrevolution]

would you also support him mixing different resins with tenacious to get the ultimate engineering blend?

[@MadeWithLayers]

Thanks for the tips - I'll let you guys know know when I'm back at doing resin experiments!

[@globalrevolution]

@@MadeWithLayers So far I go with 30-50% Tenacious in Elegoo ABS-like for impact resistant NERF parts, but that's trial and error.

[@sirayatech2]

@@globalrevolution we will be happy to. Blu 70% + Tenacious 30% seemed to create a good balance between impact resistance and hardness

[@globalrevolution]

@@sirayatech2 30-40% Tenacious seem to be a good spot

[@jamesbooth4016]

Really liked the cinematics during the break test clips.

[@Rocketkid2121]

Give milled fiberglass a try instead of chopped fiber, it looks similar to the cotton you used, its a common filler with composites.

[@helicopterdriver]

FLOX... pretty easy to mix in too.

[@csakip]

Tried it, it makes it weaker too.

[@Rocketkid2121]

@@csakip That's surprising, I wonder if his theory on the micro bubbles and cracks is what's causing it. Maybe in a pressure chamber or something the bubbles would be minimized.

[@shelltoe_soul]

​@@Rocketkid2121 I think it would be basically too late after you have already printed the part. You would need it to be in the pressure pot before it becomes cured.

[@Rocketkid2121]

@@shelltoe_soul I agree, I know that wouldn't be super easy to pull off and maybe not worth the effort, but it just seems counterintuitive that the fiber would weaken the print, and that test would possible eliminate bubbles as the culprit. Possibly UV resin doesn't bind well to glass?

[@andresfelipevasqueznino8618]

Hey man, great video! If you want to achieve a truly mechanical reinforment of your SLA resin you have to add functionalized fibers/particles. Functionalization of fibers/particles improves the chemical affinity between the fiber/particle and the polymer matrix. You can purchase functionalized fibers/particles ready to use or you can functionalize them yourself (using a silane coupling agent). Cheers

[@liamsmith8518]

I am excited to see a follow up for the other fiber-reinforced prints

[@Georges3DPrinters]

Tom I've been watching you for years. I very much appreciate that you're on the same track I am, for me a particular print that I am trying to make stronger for someone. Before I saw your video for the last time you added fiberglass I was at the beginning of my adventure and that time the only glass fiber reinforced prints I saw was someone making a shell and then filling with epoxy mixed with glass fibers. I am very appreciative to see that the first test with glass blankets was not that good in strength. Saved me from the mess. I had just boughten chopped glass fibers and received them when I came across your video and was like "damn it someone beat me to it". but I appreciate you going through all the messy stuff and displaying your results saves me a lot of headaches and I just want to say thank you. Also, I never thought of cotton. Brilliant! Also the graphite I want to try now. thank you for the wealth of knowledge you have shared over many years.

[@MadeWithLayers]

Thanks! Glad you're getting something out of the videos!

[@martijngeel9224]

When you use fiber glass you better remove the bonding agent with acetone.

[@cragbot1]

In most injection molded parts with glass fiber there is at least 30% fill. Most structural composite layups are at least 50% fiber

[@adrianschneider1977]

I would say with injection molding one can start at 15 to 20%weight. The major difference might be that rather short fibers are used and not large pieces like 3mm long. My understanding is that something like milled fibers (carbon or glass) might work similarly to the way it works in injection molding.

[@gutrali]

Seems pretty obvious the fibers need some treatment first -- as they are melted and mixed together before the injection mold. Right?

[@MrEratrace]

@@gutrali On materials I worked with we bought the pellets already made, you want abs-GF30 you buy abs-GF30 pellets so they are even already mixed during batching ^^ You can mix longer ( a few millimeters) fibers in the barrel but it requires special coatings and geometries as I recall so as to dont break the fibers

[@jakobrosenqvist4691]

@@gutrali fibers like the ones he usess are bonded with styrene, sobthe resin needs to be able to dissolve styrene to be able to soak in to the fibers properly.

[@skimbulshanks]

I like the music montage of the stress testing. I never cared to watch each and every test. One test filmed to show the procedure, yes, but then cut to the results. Your presentation was very enjoyable to watch. I wish more people would film this way.

[@MakeTeachRepeat]

I've printed cycloidal gears with graphite additives, also adding a small amount of flex filament to 10%. Makes for a very strong part that is partially self lubricating and tough. The flex adds more strain relief albeit at the sacrifice of rigidity- but that slight flex is great to make up for the slop and inaccuracy of the print.

[@winstonsmith478]

I would be interesting to see the LCD replacement process.

[@gotsane]

I would as well considering I picked up this exact setup today (machine and wash station)

[@thecalvaro]

Hi Thomas, great job. Your videos are inspirational. Btw, I am a materials eng. Scientist. Is a long time that I don't get into the polimers side, but as you analyzed, add fiber or other materials can deteriorate the properties because a lack o bound between the matrix and the aggregate. It not necessary forms micro cracking around but can help the cracking propagate faster on the aggregate material surface because it's is not properly bounded. Most composites have a mix of polimers or other compounds that helps bound the matrix to the aggregate, same principle of soap and water to remove fat. Let me know if you need more information about it.

[@postalcollective7111]

Hours and hours spent to make this. Awesome Science-ing. Mind you it has given me clues for resin printing. I was so keen to cut over to Resin printing for the absolute beauty of the outputs, snag is the parts are not tough enough for me.

[@RinksRides]

One thing to note: Short fibers are useless for strength or structure. However, I believe by adding the short fibers to your resin, it may have a larger impact on ABRASION resistance, than adding strength. Being in custom/restoration/collision for 30 years, when I have to fix an older Corvette door I use the long strand glass mat for structure then a shorter fiber/filler mix to cover any hard edges before applying a finish putty before primer and paint. USC Duraglass, and a product called Fiber-all are basically body fillers with short strand glass fibers pre mixed in. I use them sometimes where chipping might be a problem, like a corner or edge of a door for example, where the panel doesn't line up perfectly to the next panel. Hope this helps. Been subscribed since I bought my Wanhao i3 v1.2 back in 2015 (currently rocking an SKR 1.4 and 2209's), and since have upgraded the poop out of it thanks to more than a few of your videos and tutorials. I have a Mars 2 Pro also and found this video very interesting and educational. Cheers from the USA!

[@bjrn-oskarrnning2740]

Man, the editing during the testing was A++!

[@choschiba]

I really enjoyed watching the video. I can imagine how messy those tests must have been. As this video was recorded two years ago, it would be great to see how the new generation of resins would perform. Without mixing anything additives into them, but mixing resins with each other.

[@alexboesen5985]

The graphite results with regard to visual appearance and potential for self-lubrication are definitely interesting. Worth keeping in mind. Loved the music/stress test montage. You are definitely stepping up your video productions.

[@AnthonyClay]

self-lubrication would actually be a fairly big deal. 3D printed/integrated bushings and thrust bearings were my first impulse.

[@UnvarnishedTarnished]

I absolutely love graphite powder, I combine with epoxy resins all the time when casting

[@vwegert]

Me: Maybe try glitter? Katelyn: Hey, Evan - hold my beer...

[@yardenfadel8172]

Right

[@AmaroqStarwind]

Haaaaaaaaaaaaaaaaam! "Ham! Ham!"

[@flymypg]

I very much appreciate tech creators who also show failures, not just success after success. That's the engineering/scientific process. Good engineers/scientists have a high tolerance for failure, building on it rather than giving up. It is often the failures in pursuit of a goal that create spin-offs enabling entirely new directions and new goals. Such as adding carbon for color and perhaps lubrication, rather than for strength.

[@Mr.Donahue]

Some one has been watching project farm.

[@androiduberalles]

I was waiting for the "We're gonna test that" t shirt to pop out of nowhere.

[@THESLlCK]

@Greg Tubby that guy is incredible

[@SebastiaanSwinkels]

At 8:30.. maybe lock your vat down?

[@scruffy3121]

Just what I thought 😂. Layershift incoming.

[@chrismorrison9140]

I saw that too. And have done that too.

[@RinksRides]

@@scruffy3121 no layer shifting, it's not the build plate moving around.

[@scruffy3121]

@@RinksRides yeah. Didn't think about that properly. Still can't be good for the display, vat or noise level. Is the fan in the mars Pro 2 as loud as the fan in the mars?

[@dodobarbar]

Exactly :-)

[@Arick_Lee]

I appreciate you runing all your equipment and free time to hopefully help me avoid doing so as well

[@herllraiser6662]

Ive been adding stuff to my resin for months.. but you got to remember the way the layers work to get some nice effects for knife handles and models.

[@davidboston7943]

Very cool experiments, thanks for showing your results! My one contribution as someone with a materials science/mechanical engineering background is to remember that there are still more mechanical properties than strength. A lot of times composites represent a tradeoff between stiffness and strength, where you increase the stiffness over the base resin/matrix, but make it more brittle. This would reduce the energy absorbed during impact. With the short fiber systems, though, you tend not to see much increase in strength, particularly at low volume fractions, because you don't have enough load "continuity" for lack of a better word. In long/continuous fiber systems, for example, even when the matrix fails, the fibers can still bear load. Here, there's enough space between fibers that failures can just propagate through. I'd also agree with other comments that improper bonding/wetting between fiber and resin could contribute. Could be interesting to look at in future tests. Doesn't require an electron microscope, just a decent power optical. You can even experiment with the $20 or so digital microscopes to see what kind of images you can get.

[@scholli485]

Great Video Thomas! I never tried a resin printer, but I have some experience with glass and carbon fibers. I think some other fillers could also be interesting. There are for example glas micro balloons with 0,12 g/cm^2 and a particle size of just 65nm to make very light weight components. To reinforce the resin a good try could be to mix milled glas fibre (0,2 mm) and finer cotton flocks (0,35 mm fibre length). Some fumed silica like Aerosil could also help to thicken the resin, that the chopped fibers don't saddle down to the bottom. It looks a bit like, that the chopped fibers in your prints are not completely wetten, normally they should get very transparent in the resin.

Freaking love my elegoo. Been mdf printing for years but avoided sla because I'm very allergic to IPA. But saw the water washable resin and jumped in. Been printing non stop for a couple weeks now.

[@dragonling748]

The best method of reenforcement I've found is likely not what your looking for. But when I need strength, I print with a hole though the part and use an epoxy resin to secure a metal rod inside.

[@kaltland765]

Say more… you make a hole in the model and then fill it with resin? Is that the idea ?

[@dragonling748]

@@kaltland765 More like use the epoxy as a glue for metal rods

[@dblattert]

Really love the SLA experimenting!

[@davidgutting4317]

I plan on making bushings and gears with graphite. Guides as well. Great video.

[@rickf7445]

Nice methodical approach. I found your videos because I wondered about adding fiber materials to the resin mix to improve strength. I would repeat some of the experiments using "tough resin", which has ground rubber mixed in to reduce the brittleness. Use a squeeze bottle to blow a little milled carbon in the first 5 and last 5 layers. Blowing will confine the carbon to the outside layers while keeping the inner layers almost pure resin. It will create a stronger skin on the outside.

[@basic48]

Light is reflected from the outer surface and the inner surface of the bubbles, As the thickness is very thin,there is a difference in the refraction angle and it forms a miniature prism effect. Love the experiment.

[@SplicesAndCelluloid]

Good to see that 5% of Colton made it into a print. :P

[@Litruv]

I liked this video - seems different than most recent videos to come out recently - was getting tired of everyones printer reviews, thanks mate :)

[@RM_VFX]

These results make sense...the strength of resin comes from the cross-linked polymer chains. Any foreign fibers you're adding just means there are fewer of those chains, and those fibers are stronger when locked together than chopped up and mixed with a foreign substance. The graphite did look cool though.

[@MrStudioso]

Dorsnt the fiber impede the curing light from shining through? Especially the carbon I would think would absorb the UV

[@michaelnoble2432]

Yes, this is what limits how opaque 3D printing resins can be, and why a solid black (for example) isn't really possible from what I've seen. You need to get enough light through (say) 50 microns to cure the layer.

[@Dzeno2010]

@@michaelnoble2432 yes and no, light absorption is also wavelength dependent. However since most use 405nm it's kinda hard to have something that's really dark. There are blacks that are close though and depending on special use cases a very dark resin for a special printer could be made.

[@notsam498]

This is what I thought. For sure the fibers must screws with the light curing the resin right?

[@matiasrinaldi1538]

I once made epoxy resin reinforce with carbon nano tubes, in several concentrations, it did not improve the tensile strength but they where more conductive.

[@prestonengebretson2920]

Great Video Thomas...you ask about the reason why the filled parts are loosing strength...most fillers in a resin binder system need an additive that allows the resin to bond to the surface of the filler. Otherwise, as you have shown...the properties will suffer. One of the more common families of bonding or coupling agents is silanes from Dow Chemical...depending on the resin, the particular coupling agent is chosen for a particular filler...I formulated 2 part spray-able polyurethanes and polyureas that after leaving the spray gun would be dry to the touch in just seconds. Your other problem is likely you need a Much Higher shearing action of the reinforcing materials far beyond what a magnetic stirrer can provide...they are fine for liquid to liquid mixing, but Do Not really totally wet out the surfaces of the filler to liquid interface. Thus, first you need to find the proper coupling agent for the fiber and polymer, second use a High Speed Disperser, and finally vacuum out all of the air bubbles. Keep up the Great Work!!!

[@ThatSwedishGuy]

I'm close to buying a resin printer and is still learning about them before my purchase. My main hobby is RC cars/trucks, where we use dry wall to reinforce the body shells, and of course most knows that the higher quality cars always have a composite plastic used. Maybe this would be your source of information? I have for some time tested parts for a manufacturer and the character of the parts significantly changed depending on direction/amount of fibers used. But the key secret is that the fibers are overlapping so the force can't slip through, but still in a small amount that the parts still have flexibility. Great videos as always Thanks you

[@g45h96]

The problem is that in a composite material, the purpose of the resin matrix is to transfer load from one fiber to the next. If you don't add enough fiber, you're just introducing impurities and therefore reducing strength. And you can't add enough fiber and still have a successful print with the way that lcd/sla printers operate.

[@mausball]

It's only a theory, butI believe the fibers will impede the ability of the resin to fully cure by occluding the light paths to all areas of the resin. The masked resin is left to cure partially with refracted light from the subsequent layers. I'm not a composite expert, but I've been around materials a lot, and have some related experience.

[@ameliabuns4058]

I really wanna try to make a continuous fiber laying tool for my doot changer but i'm tired and lazy and doubtful i could get it working, specially with my tools and skill! BUT THIS IS WHy i love this channel so much :D awesome video!

[@Runoratsu]

„We're gonna test that!“ Getting strong Project Farm vibes here! 😄

[@ZakLeek]

That was a brilliant test montage! 👍 These experiment videos are so good, they explore concepts I never would have otherwise come across, thank you Tom! 💙💜

[@Khether0001]

the colors on graphite bubbles are caused by an effect called *thin film interference* , where basically light passing through the upper and lower part of the bubbles interfere with one another enhancing the reflected light.

[@DoRC]

Look up epoxy thickener. Not only is there much finer fiberglass options but there are also other options that would be cool to test.

[@mr89firebird]

So, I just watched Tech Ingredients' video on making graphene, and he showed an impressive increase in the bending resistance strength by putting a tiny amount of graphene in some epoxy resin. Of course, one of my first thoughts is if this could be used in UV resin. Would love to see you do a video on this!

[@justins4d]

I was hoping you'd mention the lubricating effects of resin, glad you said something at the end. It makes me think of oil impregnated bushings. In addition to that, I'm very curious about thermal conductivity of those graphite parts. We messed around with some plastics at work filled with something and I want to say it was graphite. Although they lost flexibility, they had a very "cool to the touch" feel and that's exactly what we were going for. Trying to get thermal transfer improvements through the part.

[@trkoo]

Love it! Please do more resin review videos, we would love to know which resins to buy as there are many confusing products out there.

[@ghostwheel9935]

Add metal fileings. Place resin vat in a magnetic field to line up the filings.

[@adolphsfather4834]

The field might mess with the screen used to cure the resin though, correct me if im wrong.

[@SatyricSaint1999]

I work for a National Laboratory and 3 years ago we tried Graphite and/or Iron filings in the resin of a Laser SLA printer to try and see what concentration (if at all) it would take to get conductive/magnetic properties out of a 3d printed part and determined really quickly that at higher concentrations the slurry becomes to tick to work with the printer and at the maximum saturation point that does allow the prints to work the resin acts like an insulator at a microscopic level and simply will not allow a continuous current to run through it.

[@littlesnowflakepunk855]

The reason for the "holographic" effect you saw in the graphite resin is that the flakes of graphite are orienting themselves with the flow of the liquid, so that their reflective surfaces are tangent to its flow - creating what is known as a "rheoscopic" or current-showing effect. In the bubbles, I'm pretty sure what's happening is the super-fine particles of graphite are causing an effect called thin-film interference, where the reflected light from the top and bottom surface of the material are different wavelengths and start to interfere with one another, causing those wild colors to emerge. The same effect is visible in soap bubbles to a milder degree

[@mr89firebird]

Dude, LOVE the editing in the montage for the testing!

[@havoc092]

Not a materials engineer either, here; but, you can think of what you're doing as creating inclusions in the resin. Inclusions in metal causes the metal to fracture over time in certain conditions. If the particles you are mixing in are larger than the particulate size of the material making up the resin, you may or may not get a good bond. Remember, in fiberglass for example you are working with a woven cloth base that already has strength in and of itself. By incorporating simple fibers, you don't have the strength you tend to get from weave. And if you aren't careful with the resin application, it won't soak through the weave - leaving voids and leading to delamination. Love seeing you do these tests tho. This is the core of the hacker experience - test, experiment, learn. And good to see Siraya Tech chiming in. Though it does make me wonder if approaching this with a fine weave material at each layer or every so many layers would make a difference. Food for thought. Something like silk...

[@sierraecho884]

If you want to improve the mechanical properties of your resin parts, you can do two things. 1.) Print at an elevated temperature of 25°C-35°c 2.) Cure under water (prevents oxygen to inhibit the curing process) + cure under hot water (heat equals vibration, vibration helps in the bonding process between the molecules during curing). Both of those measures should help significantly (About +50% more strength) Adding anything to the mix weakens your parts since those molecules can not bind properly anymore and have to bridge a gap because of the "impurities" you have now introduced. Fiber reinforcement works well with epoxy resins because those don´t need UV light to cure, properly mixed they will always bond to anything.

[@userIDONTKNOW]

You should try cotton and fiberglas at the same time. The cotton makes the resin thicker, so the fiberglas can stay chaotic in the resin and doesnt sink to the bottom and stay flat. But maybe the printsurface squeeze everythink down and flatten it. Thats why a bigger resin container could be needed. So the fiberglas mixture can easier flow to the side and back after the printsurface goes down and up.

[@Anaerin]

I think a lot of the problem with this is that, while the particles (cotton and chopped fibre especially) are adding strength to each layer, they are only adding strength within that layer. Because of the way SLA builds the object, you're not getting any cross-links between layers, so it is exactly as strong as a normal object in unenhanced resin.

[@SethAltobelli]

You can get kevlar that is similarly fine to that cotton. May be worth a try...

[@brengilmore2933]

I'd be really interested in seeing additional testing with both the milled carbon fibre powder you mentioned, as well as a more fine glass particle powder. These are the two materials I've been thinking about testing myself recently, and I feel like have the best chance of improving the material properties in some way. I have personally been interested in these two materials to help improve rigidity more so than ultimate strength, in order to create lightweight, thin, yet rigid and still acceptably durable materials. Something I've seen on the topic of the glass powder specifically is Formlab's Rigid series of resins(Both their Rigid 10K and 4000), which are claimed to be glass reinforced resin. Specifically for their Rigid 10K, they claim "Simulates stiffness of glass and fiber-filled thermoplastics" and describe it as "This highly glass-filled resin is the stiffest material in our engineering portfolio.". This to me seems to suggest that it's likely just a simple glass powder mix, which also leads me to believe other suitable materials(specifically milled carbon fibre) mixed using a similar method should produce good results. This along with a strong base resin such as some of the engineering resins from Siraya Tech like Blu, I think could potentially produce some nice results. Great videos by the way, love them, keep it up :) I'm excited to see what other tests and videos you create in the future.

[@yomboprime]

8:30 The vat is moving up and down with the moving platform?! (See corner on the right) Did you forget to tighten the two screws?

[@keezo1234]

Interesting idea for Thomas: Make replaceable Gibs for a dovetail mill out of graphite infused resin. As the resin is worn away the nodules of graphite can act as dry lube for the mill ways

[@richardcox4000]

When you start your print hook up a pwm as it prints out so that when it prints out with the graphine/graphite, there will be a line for the electricity to follow

[@johgranger1304]

PUT the glass fiber in a blender to separate them, if it doesn't work heat them to destroy the binder. (Thank you so much for testing this!)

[@bellers85]

I like the visual effect of the graphite. I wonder what it would look like if you were to use some of the pigments that they use in poured resin tables, coasters etc.

[@MrGhris]

Nice video, suprising results! Maybe cleanroom wipes as material? Either chopped up or in layers. Those are a bit like paper towels, but specifically designed to not shed particles and are extremely strong in one direction. So if you criss-cross the layers it might result in a really strong part.

[@iFilipis]

Yep, confirm what many people say here. Milled fibers or glass spheres are usually used as reinforcement. Large chunks of GF in small quantities are just useless. Hoping to see the update to this experiment. Also, GF should be mixed by volume, not weight. Try 30 to 50%

[@pistruiatualin]

At 8:30 my heart just dropped. Made that mistake before. You forgot to tighten the screws for the resin vat

[@MadeWithLayers]

Oh, you're right! Didn't notice that I had that footage in there 😅 Rest assured that I redid that print

[@pistruiatualin]

@@MadeWithLayers Glad to hear that and glad to see that germans make mistakes too :)

[@britzwickit]

@@pistruiatualin we are kinda famous for making one of the biggest mistakes in history ;)

[@andreapiseri8521]

The colored bubbles look like interference between the light being reflected by the outer and inner surfaces of the bubble's wall, which boost a certain frequency depending on the wall's thickness. I think the reason why these are visible is that the graphite is accumulating at the interface between resin and air, which makes for a partially reflective surface

[@MartinXScott37]

Ferrous and Nonferrous metal powders are available in various micron sizes. Also, some mica powders glow in the dark and have color shift. It would be really cool to see the properties of copper powder, aluminum powder, silica, ceramic and color shift mica powder.

[@rodryk5605]

Hi Tom. Gr8 video. The reason the graphite bubbles are shinny is probably due to thin-film interference. Also if you want try out graphene (1-3%) should do the trick. I suggest you make it yourself, just buy a ultrasonic cleaner, get some graphite electrodes from zinc-carbon batteries and a bit of ammonium sulphate (common fertilizer).

[@roderik1990]

On the colourful bubbles, I think another explanation is that bubbles are just always colourful (from interference on the thin layers) and the dark graphite behind it just provides good contrast.

[@anthonypalacio8322]

The glass fibers are clumped together because they're coated in something called a sizing agent. Sizing agents are essentially coatings that cover the fibers. Because glass fibers are chemically inert they will not bond with any kind of resin or epoxy matrix. These sizing agents have two fold benefits, they allow for this chemical bridge (aka a coupling agent, for glass fibers it's typically a silane) to bond to matrices and add a protective layer to the outside of the fibers for easier handling. They also bond the fibers together, that's why its so hard to pull the individual fibers apart, they're essentially glued together. That being said you can just sonicate the fibers to loosen and separate them.

[@mfx1]

You can get specific fibres for re-enforcing concrete floors they're chopped fibreglass but single strands, not clumps like you used.

[@fahb68]

Another great video, thanks... a sugestinon is to use microbaloons, (for ligther pieces), a ligther piececould be a great caracteristic depending where is use the part

[@andrewfredrickson7280]

The reason it appears those colors is that it is a conductor and the electrons are in the conduction band and this means the electrons will easily absorb any amount of energy including different wavelengths of light and it absorbs them all.

[@davenzor]

"We're gonna test that" My favorite to hear.

[@nixnocent88]

Give thermally expanded graphite a try

[@andrewchudyk8518]

Tom, I reckon that the graphite is so opaque that it's not letting the UV through the outer shell of the part to properly cure the inner. That could explain why adding more makes the part weaker.

[@MsBlood01]

I'd love to see a video on adding pigments, inks and glitters just for make resin printing pretty. i was just talking to a friend about the hand made dice she makes and i was like....i should be able to 3d print dice that pretty

[@helicopterdriver]

Have you tried heat soaking any parts? Form Labs has a process to do that. It supposedly allows the bonds to increase from migration and post curing of semi cured resin.

[@adama1294]

What might be good to try for artistic looks is mica powders. They are used in resin projects but haven't seen in SLA.

[@kendrickeducationassociati347]

After degassing, if you VERY briefly blow hot air over the top of the liquid from either a heat gun or torch, you will get rid of the bubbles on the top.

[@Sharpevil]

The most popular additive for improving tensile strength is probably Siraya Tech Tenacious resin. Everyone seems to have their own preferred ratio. I'd love to see this kind of rigor put to testing different ratios. Maybe you can get Siraya Tech to sponsor a video.

[@gisbertschleusser9950]

For the look and possibly for conductivity: please try metal powder. They're available down to 5 microns (at least in aluminium). Keep going!

[@incinerati]

One type of fiber that comes to mind is nylon fiber used for reinforcing concrete - not sure how it would mix, as it comes in longer fibers. Anyway, thanks for testing this, you saved me a lot of effort and potential damage to the printer! :D

[@laurinos8774]

I never did any experiments with resin prints but I have used imbedded needles or piano wire in FDM prints. I guess you could print channels into the parts and and pull long strands of fibres covered in epoxy through these holes. Or even take it further and print a thin walled mould in resin and then fill it with resin and fibres afterwards. The final part would benefit from the shape of the printed part and the more controlled placement of fibres.

[@spanditime4170]

I think a great idea to test is trying to print on higher temperatures. Heat the vat and print and see how it affects the part. Bc polymer chains would usually be longer under higher temperature, and the material might be slightly better in terms of strenght, heat resistance etc.

[@KiR_3d]

Hi, Thomas! I think you need just a bit of cryptonite and then the prints will be stronger than titan! :)

[@orhanyor]

great video and surprising results! while watching the whole video i was thinking about the milled carbon fiber im glad you mentioned it. i have exactly that milled carbon fiber and i mix it into the polyurethane resin for casting and i can say it does make the end product stiffer and abit more stronger but for resin printing im not sure what to expect. i also use graphite powder mainly for coloring and like you said its amazing. Its worth mentioning theres also milled glass fibers just like the milled carbon fiber and it should prob provide more or less the same characteristics. pro side might be better signal penetration if thats what you are dealing with because carbon fiber is notorious for blocking radio signals like bluetooth etc.

[@alexhise968]

Thin Film Interference is where the color is coming from and the black background gives greater contrast

[@michaelryan8547]

Kevlar/aramide pulp might be interesting, if it doesn't add strenght it might add some abrasion resistance

[@hayden9944]

The form 2/3 has a fibre filled resin. I think u need small chopped strands. Large enough to connect or bind resin to increase strength but small enough to mix evenly to stop stress concentration

[@ddtalks2821]

Removing Bubbles - If you watch any of the acrylic mold Dice making videos, they use a lighter to pop the bubbles that form on top after they vacuum extract the air. You might try that next time.

[@DC-ox4rc]

12:55 didn't expect the sound there and it made me jump out of surprise.

[@perfectly_unstable]

Not sure if it's been mentioned. I use resin as a filler/primer by mixing it with sodium bicarbonate, about 40/60 and it helps the resin thicker and stays suspend quite well. It could help hold the heavier filler/additives.

[@kaltland765]

Which resin do you use to fill your model?

[@aomanchutube]

I think it makes sense that the parts become more brittle. Compressively strong materials are brittle. Tough materials on the other hand are more bendy. I think you basically make the parts more rigid.

skinning the parts in fiberglass after printing does work, idk how much "strength" it adds but it looks good and isn't hard to do.

[@Averell64]

I have an idea for the lowering in impact resistance - in cast iron there's two kinds, one where the graphite has a lamellar shape and one where it has a spherical shape (GJL and GJS). The one with lamellar graphite has a lower impact resistance due to "inner notch effect". Around the lamellar shapes you have a lot of "notches" and sharp corners that are a great start for cracks to form. Essentially a tiny predetermined breaking point. I'd expect the effect to be similar when having particles in the resin.

[@johnvanderpol2]

I used paint with graphite added to make prints conductive for electroplating. After painting you need to brush it with iron wool to make it conductive, to expose the graphite Maybe you should try that on your prints