To reinforce parts it makes no sense to put the reinforcement e.g. carbon fiber into the middle of the part. This is the neutral fiber and will therefore not strengthen the part against bending. You have to find a way to put the fibers more outside of the material where compression respectively decompression takes place. The epoxy is good for compression, while the fibers are good for lengthening of the part.
Exactly. Resin is great for compression, whilst fibers, such as this or rope are best in tension. You wouldnt use a coil of rope to hold a heavy object off the ground, but rather you would use said rope to lift an object off the ground. We did these tests in strengths of materials lab.
Kudos for pushing the envelope and taking the next step. CA (super glue etc) works great with carbon fiber. A print with the minimal wall and infill that you can make stable enough for placing the carbon fiber could be very strong. 3M 77 or similar adhesive will make it easy to place the carbon fiber tape. When you are satisfied, add CA, or epoxy. Don't expect the print to add structure, use it as a form. CF w/ CA or epoxy has a much higher strength:weight ratio than any print. Thanks for the inspiration.
I was going to say the same. Put a vacuum hose one the other end and draw the epoxy in. Not sure how the bubble entrainment may go but it should provide better results given how popular vacuum infusion already is.
3d prints do not hold water ever under any circumstance, let alone air. If you leave even solid prints in water you will find that water has worked its way in and the part will mold even on the inside as seen in clear parts... Granted I live in a very humid environment.
Tip: resin doesn't stick to silicone sheets, to make a silicone sheet, use caulking paste sandwiched between 2 plastic sheets, then release the plastic sheets
The epoxy injected parts will probably be quite strong in compression. The carbon/epoxy matrix strength depends a lot on the ratio of carbon fibers to epoxy. A 50/50 layup is considered to be achievable for an amateur working with wet layups. With pre-preg carbons it is higher. (and you can go too high, and achieve an epoxy starved layup if consolidation is done with positive pressure instead of vacuum. From the videos I guess the ratio of carbon/epoxy was substantially below 50/50. That might be one variable explaining the measurements. Another variable is strand orientation. Twisting the fibers will cause the layup to be weaker as compared to straight fibers. If you could achieve similar weight between the epoxy/carbon layup and the steel wire, I would be interested in the results. The carbon/epoxy layup should be significantly stiffer than the steel/plastic fusion and thus take all loads instead of working as a composite steel/plastic part. The epoxy used, curing time and temperature are also some variables that might be influencing the measurements. "Cooking" the part in an oven for 8 hours at 80degC and then letting the part sit at 20degC for a day or two might change the results a bit. If it was the epoxy matrix, not the carbon/epoxy composite, that carried the tensile loads there might be significant changes. Cool experiment and video! You cerntainly thing outside the box :-)
@@leonbrauns There are plenty of additives for epoxy you can try for the parts where continious fibre is not possilbe or not worth it. Chopped carbon fibres or milled carbon powder for strenght, glass microspheres for lower density, lots of metal powders or even Aluminium Trihydroxide for fire resistance. I would love to see some destructive testing of carbon particles epoxy filled 3d prints. Also chopped fibres and powders are usually quite cheap. *WORKING WITH CARBON BASED POWDERS AND PARTICLES REQUIRES USE OF A RESPIRATOR!!!!!* (unless you really like cancer). Luckily p type filters (particle filters) are the cheapest
Playing with temperature is interesting idea. I think what you were describing is annealing the plastic. I dont believe this will impact performace, bare in mind that the epoxy cures at room temp and does not have large internal stresses, nontheless it is a cool experiment You can also play with curing temp. You might be able to increase the degree of cure by a few % by heating the part up during curing. Usually after 90% degree of cure the mechanical properties of the resin dont change that much and I guess you are already in that range, however, that does not mean you can't get a slightly higher Tg for the epoxy. Nonetheless this is not very important since the pla shell can not handle large temps
For years i use abs with carbon fibre....i just put carbon fibre mid print , add a few drops of acetone and resume the print :) for method you use....i use it too :) but for easier aplication i twist filament few times then aply it or aply resin before puting it in print and add rest of the resin after.
Epoxy itself isn't very strong in tension. It's only designed to bind other materials for that purpose. You probably would get good results with epoxy reinforced infill as long as the infill is tight enough.
Bravo! Very interesting video, I would suggest checking into Kevlar tow/fiber as it is very cheap and strong in large spools, similar to CF. I have tried both with success. I would also suggest it because it is much less messy and stays in a compact fiber very similar to string. Finally it would be worth checking into purpose-made CF epoxy resin since it is made specifically to bind to fiber and the stuff I got has a nice slow cure time and works well. You might try JB Weld alone since it is among the very strongest epoxies out there, it would be difficult to inject around fiber.
if instead of printing the part then reenforce with carbon fiber, you 3d printed the mold then make the carbon fiber part around that, it will be even stronger. and lighter.
Epoxy resin doesn't stick to many plastics. That's why plastic sheets are used in vacuum bagging. So in your experiment there is very little adhesion between the epoxy and plastic encapsulation. From plastics, PVC and ABS stick decently to epoxy if you roughen the PVC/ABS surface. So to increase adhesion you could artificially 3d print rougher surface (or few lines of grid) inside the channels and/or try using wood PLA.
Some great ideas here. Not sure the application or usefulness, but thanks for sharing your experimentation and results. Ideas outside the box are what make makers' lives fun. It might spark off other ideas from this until something awesome is invented.
Some people cast resin with metal powder to make magnetic or durable casts. I wonder what the results of this kind of 3d-print liquid resin injected parts would be with different hardening or bonding materials added to the resin.
Perhaps you could chop the carbon fibre into fragments of a few millimetres, then stir them into the epoxy before you inject it into a part. You might need to use zero infill or multiple injection holes to let the fibres reach throughout.
Thanks for doing all the leg work and thinking of ways to DIY stronger parts. I have been filling parts with resin for a while but my biggest problem is getting the prints to be water tight. What sort of settings where you beefing up to make sure there aren’t micro gaps in your layers?
3 perimeters and at least 10 top/bottom layers. If you still have problems, increase your flow rate or hot end temperature to make sure your layers are bonding together nicely.
so instead of injecting the resin, would it be better to use a small vacuum chamber filled with resin so that it sucks the air out, then as the vacuum is released the resin is forced in. Like how they get resin into wood for knife making
It might be good to try cutting the carbon fibres to 1mm or a bit longer and mixing them with the epoxy before injecting so when set the material has a non uniform grain that should make it stronger than epoxy alone and you could get the fibres into the part through a hole if it would come out of the syringe at all! Nice vid though, I was wanting to try this myself for the MPCNC parts.
Holy shit this is amazing. I don't get why carbon fiber that look like strings can make something so much stronger and stiffer. I wanna see if I can make a toolhead that can lay the fibers... If only there was some fibers already made into a filament like shape with resin. I could cut them when I'm done and push them with regular extruders.... EDIT; HOLY SHIT IM HYPED DUDE. THE STEEL injector tool should be easy to make! I'm so hyped if I get the time. but I'm gonna use copper cable (for power etc) because steel is super hard to cut.... Unless I do multiple thin steel wire passes
I used Carbon Fiber in the first whole body CT scanner. We made flat sheets with resin and microspheres for xray translucence. Then we put low density rigid in the center. This sandwich type construction, we had strength and low xray absorbsion. I would use two nozzles. 1 infill 2. Carbon impregnated. Layer 1 carbon, infill then outer layer carbon.should make a strong plate like part.
If you want to strengthen your part you need to wrap the carbon fiber and epoxy around the parts by using a paintbrush to brush the parts with a thin layer of epoxy and layer a thin layer of the carbon fiber over the top and brushing with epoxy again, then sand and repeat 1 to 2 more times.
So whenever you do an injection, you really should be injecting so that the air escape port is higher than the lower port as to prevent air bubbles to start with. Second, carbon fiber works best on the outside. Third, your last part did not have carbon fiber through the base, where it’s most likely to break.
ok so the material is going to brake starting from its surface since the stresses there are generally greater on bending and due to stress concentration. Filling the material with fiber-epoxy doesnt increase greatly the strength for that reason and for the reason that in the carbon-3d printed surface you only have epoxy as a binder wich im not sure is a good match from your results(way different elasticities).
I think that slicer software should have features that they don't have today (AFAIK): print over done pieces. This will allow us to put reinforcement in the middle and use pre-printed reusable support.
important thing you miss - there are hundreds varieties of epoxy resin... (epoxy glue from store not the same epoxy resin). with very different properties. usual epoxy strong and fragile, but it can be flexible to. also different fillers can be used, not only carbon fibers. and same - very different properties. I think 3d printout resin filling still open for lots investigattions.
For the longitudinal screw part at the end of the video why not have holes at both ends of the screw, you can then thread the fibres through with a rod or 'needle' repeatedly so its like a bobbin and you have many parralel tow threads. You then cut the looped ends at the top and bottom, seal the cyclinder and pour in the epoxy.... You should be able to get a much denser 'infill' this way. Btw. for bigger parts what about standard infil and load up those 'pockets' with chopped fibre + epoxy mix... I.e. the printed part walls becomes the mould for an internal 'forged CF' part: th-cam.com/video/25PmqM24HEk/w-d-xo.html
Die größte Belastung bezüglich Zug oder Druck tritt in der Hülle auf. Deshalb hat die Evolution hohle Knochen geschaffen. Bei so simplen Teilen wäre es also zweckmäßiger eine wiederverwendbare Negativ-Form des Objektes zu drucken (oder zu fräsen). The greatest load in terms of tension or compression occurs in the hull. This is why evolution has created hollow bones. So with such simple parts it would be better to print (or mill) a reusable negative shape of the object.
You can purchase carbon fiber that has been milled Into almost a dust form. You could then mix it into your resin and fill your parts with that. You must use the vacuum. Your syringe method is very flawed. Also you can purchase carbon fiber in a braided form that could be inserted into your part more easily than a simple tow which is what you are using now. Lastly,I different is epoxy would work better. The cheap stuff that you buy on Amazon it’s too slow to cure. The faster any epoxy cures the harder it will be.
To reinforce parts it makes no sense to put the reinforcement e.g. carbon fiber into the middle of the part. This is the neutral fiber and will therefore not strengthen the part against bending. You have to find a way to put the fibers more outside of the material where compression respectively decompression takes place. The epoxy is good for compression, while the fibers are good for lengthening of the part.
Exactly. Resin is great for compression, whilst fibers, such as this or rope are best in tension. You wouldnt use a coil of rope to hold a heavy object off the ground, but rather you would use said rope to lift an object off the ground. We did these tests in strengths of materials lab.
@@LT72884 Good example with the rope!
@@DocMicha thanks. Still an interesting video. Glad to see people doing tests like this.
DocM this is true, however it’s much harder to wrap a part in fiber than it is to embed fiber in a part.
@DocM Hey, do you happen to be an alt account for the Minecraft youtuber DocM77?
Kudos for pushing the envelope and taking the next step.
CA (super glue etc) works great with carbon fiber.
A print with the minimal wall and infill that you can make stable enough for placing the carbon fiber could be very strong.
3M 77 or similar adhesive will make it easy to place the carbon fiber tape. When you are satisfied, add CA, or epoxy. Don't expect the print to add structure, use it as a form. CF w/ CA or epoxy has a much higher strength:weight ratio than any print.
Thanks for the inspiration.
Try applying a vacuum to one port and suck the resin through instead of pressure injecting it. It’s the way “Vacuum bag” carbon fiber parts are made.
so the printed part act as a vaccum bag?
I was going to say the same. Put a vacuum hose one the other end and draw the epoxy in. Not sure how the bubble entrainment may go but it should provide better results given how popular vacuum infusion already is.
The printed part might be porous you will need to put a vacuum bag over it to stop air intake.
3d prints do not hold water ever under any circumstance, let alone air. If you leave even solid prints in water you will find that water has worked its way in and the part will mold even on the inside as seen in clear parts... Granted I live in a very humid environment.
Tip: resin doesn't stick to silicone sheets, to make a silicone sheet, use caulking paste sandwiched between 2 plastic sheets, then release the plastic sheets
The epoxy injected parts will probably be quite strong in compression.
The carbon/epoxy matrix strength depends a lot on the ratio of carbon fibers to epoxy. A 50/50 layup is considered to be achievable for an amateur working with wet layups. With pre-preg carbons it is higher. (and you can go too high, and achieve an epoxy starved layup if consolidation is done with positive pressure instead of vacuum.
From the videos I guess the ratio of carbon/epoxy was substantially below 50/50. That might be one variable explaining the measurements.
Another variable is strand orientation. Twisting the fibers will cause the layup to be weaker as compared to straight fibers.
If you could achieve similar weight between the epoxy/carbon layup and the steel wire, I would be interested in the results. The carbon/epoxy layup should be significantly stiffer than the steel/plastic fusion and thus take all loads instead of working as a composite steel/plastic part.
The epoxy used, curing time and temperature are also some variables that might be influencing the measurements. "Cooking" the part in an oven for 8 hours at 80degC and then letting the part sit at 20degC for a day or two might change the results a bit. If it was the epoxy matrix, not the carbon/epoxy composite, that carried the tensile loads there might be significant changes.
Cool experiment and video! You cerntainly thing outside the box :-)
Thanks a lot for the information. I am going to keep this in mind for future tests.
@@leonbrauns Yep, curing the epoxy in 70-90C (see specs) will dramatically improve it's strength.
@@leonbrauns There are plenty of additives for epoxy you can try for the parts where continious fibre is not possilbe or not worth it.
Chopped carbon fibres or milled carbon powder for strenght, glass microspheres for lower density, lots of metal powders or even Aluminium Trihydroxide for fire resistance. I would love to see some destructive testing of carbon particles epoxy filled 3d prints. Also chopped fibres and powders are usually quite cheap.
*WORKING WITH CARBON BASED POWDERS AND PARTICLES REQUIRES USE OF A RESPIRATOR!!!!!* (unless you really like cancer). Luckily p type filters (particle filters) are the cheapest
Playing with temperature is interesting idea.
I think what you were describing is annealing the plastic. I dont believe this will impact performace, bare in mind that the epoxy cures at room temp and does not have large internal stresses, nontheless it is a cool experiment
You can also play with curing temp. You might be able to increase the degree of cure by a few % by heating the part up during curing. Usually after 90% degree of cure the mechanical properties of the resin dont change that much and I guess you are already in that range, however, that does not mean you can't get a slightly higher Tg for the epoxy. Nonetheless this is not very important since the pla shell can not handle large temps
I was very surprised about the epoxy infill. I was sure it would have made some difference.
Thanks for testing this for us!
For years i use abs with carbon fibre....i just put carbon fibre mid print , add a few drops of acetone and resume the print :)
for method you use....i use it too :) but for easier aplication i twist filament few times then aply it or aply resin before puting it in print and add rest of the resin after.
Great idear, with the Carbon fiber
Good implantation!!
Thanks for sharing :-)
Now I can reinforce my arms and legs, so they don't break anymore. Thank you human 💝
I've seen women reinforcing their busts and butts. So this is nothing new.
@@CalaTec yes but I don't walk on my butt :)
Thank you for doing this experiment
Epoxy itself isn't very strong in tension. It's only designed to bind other materials for that purpose. You probably would get good results with epoxy reinforced infill as long as the infill is tight enough.
Bravo! Very interesting video, I would suggest checking into Kevlar tow/fiber as it is very cheap and strong in large spools, similar to CF. I have tried both with success. I would also suggest it because it is much less messy and stays in a compact fiber very similar to string. Finally it would be worth checking into purpose-made CF epoxy resin since it is made specifically to bind to fiber and the stuff I got has a nice slow cure time and works well. You might try JB Weld alone since it is among the very strongest epoxies out there, it would be difficult to inject around fiber.
Liking your innovative ideas, good work.
if instead of printing the part then reenforce with carbon fiber, you 3d printed the mold then make the carbon fiber part around that, it will be even stronger. and lighter.
Epoxy resin doesn't stick to many plastics. That's why plastic sheets are used in vacuum bagging. So in your experiment there is very little adhesion between the epoxy and plastic encapsulation. From plastics, PVC and ABS stick decently to epoxy if you roughen the PVC/ABS surface. So to increase adhesion you could artificially 3d print rougher surface (or few lines of grid) inside the channels and/or try using wood PLA.
Some great ideas here. Not sure the application or usefulness, but thanks for sharing your experimentation and results. Ideas outside the box are what make makers' lives fun. It might spark off other ideas from this until something awesome is invented.
Thanks for the charts.
Some people cast resin with metal powder to make magnetic or durable casts. I wonder what the results of this kind of 3d-print liquid resin injected parts would be with different hardening or bonding materials added to the resin.
Perhaps you could chop the carbon fibre into fragments of a few millimetres, then stir them into the epoxy before you inject it into a part. You might need to use zero infill or multiple injection holes to let the fibres reach throughout.
Don’t breath the chopped fibres though!
CAN YOU SHARE THE LINK TO BUY THE CARBON FIBER ROVING ?? THANK YOU VERY MUCH !!!!
Thanks for doing all the leg work and thinking of ways to DIY stronger parts. I have been filling parts with resin for a while but my biggest problem is getting the prints to be water tight. What sort of settings where you beefing up to make sure there aren’t micro gaps in your layers?
3 perimeters and at least 10 top/bottom layers. If you still have problems, increase your flow rate or hot end temperature to make sure your layers are bonding together nicely.
What kind of epoxy are you using?
so instead of injecting the resin, would it be better to use a small vacuum chamber filled with resin so that it sucks the air out, then as the vacuum is released the resin is forced in. Like how they get resin into wood for knife making
It might be good to try cutting the carbon fibres to 1mm or a bit longer and mixing them with the epoxy before injecting so when set the material has a non uniform grain that should make it stronger than epoxy alone and you could get the fibres into the part through a hole if it would come out of the syringe at all!
Nice vid though, I was wanting to try this myself for the MPCNC parts.
PLEASE try epoxy strengthing in the z axis! I can make an epoxy Injection tool for my cheap tool changer!
Holy shit this is amazing. I don't get why carbon fiber that look like strings can make something so much stronger and stiffer.
I wanna see if I can make a toolhead that can lay the fibers... If only there was some fibers already made into a filament like shape with resin. I could cut them when I'm done and push them with regular extruders....
EDIT; HOLY SHIT IM HYPED DUDE. THE STEEL injector tool should be easy to make! I'm so hyped if I get the time. but I'm gonna use copper cable (for power etc) because steel is super hard to cut.... Unless I do multiple thin steel wire passes
I used Carbon Fiber in the first whole body CT scanner. We made flat sheets with resin and microspheres for xray translucence. Then we put low density rigid in the center. This sandwich type construction, we had strength and low xray absorbsion. I would use two nozzles. 1 infill 2. Carbon impregnated. Layer 1 carbon, infill then outer layer carbon.should make a strong plate like part.
Pro glueing tip, use that readily available soldering silicone mat, nothing sticks to it. Just another silicone.
Perhaps a flat heat plate press or even a clothes iron would work better than a soldering iron.
put a mini air pump but in reverse so its drawing air from one hole with the syringe in the other hole its a resin in fusion i think
If you want to strengthen your part you need to wrap the carbon fiber and epoxy around the parts by using a paintbrush to brush the parts with a thin layer of epoxy and layer a thin layer of the carbon fiber over the top and brushing with epoxy again, then sand and repeat 1 to 2 more times.
So if the part is size specific scale it down a little bit.
It seems like you could add a mesh mid print. Just an idea
You should try filling it with a superglue baking soda.
So whenever you do an injection, you really should be injecting so that the air escape port is higher than the lower port as to prevent air bubbles to start with. Second, carbon fiber works best on the outside. Third, your last part did not have carbon fiber through the base, where it’s most likely to break.
ok so the material is going to brake starting from its surface since the stresses there are generally greater on bending and due to stress concentration. Filling the material with fiber-epoxy doesnt increase greatly the strength for that reason and for the reason that in the carbon-3d printed surface you only have epoxy as a binder wich im not sure is a good match from your results(way different elasticities).
Any progress making Lenses with cnc machine ?
Very interesting :)
why don't you use epoxy vacuum resin infusion?
I think that slicer software should have features that they don't have today (AFAIK): print over done pieces.
This will allow us to put reinforcement in the middle and use pre-printed reusable support.
This is your daily dose of Recommendation
Reinforcement
Base on my experience. I will wear glove and mask if possible all the time when am working with carbon fiber.
Good.... ain't nobody want see your fugly face.
You should either wrap your parts in carbon cloth and vacuum bag, or print a female mold and vacuum bag a sold carbon part
You can use Pre-impregnated carbon fiber.
Do you know the company reinfor3d , they have , a patent amb machine. They have a lot of experience
This is genius!
important thing you miss - there are hundreds varieties of epoxy resin... (epoxy glue from store not the same epoxy resin).
with very different properties. usual epoxy strong and fragile, but it can be flexible to.
also different fillers can be used, not only carbon fibers. and same - very different properties.
I think 3d printout resin filling still open for lots investigattions.
where to buy this carbon fiber roving my friend???
You sound like Richmond of The IT Crowd
You should really wear gloves when handling carbon fibre tow
Carbon fiber is not nearly as dangerous as glass fiber
why not print with carbon fiber or steel filaments?
Those tiny carbon or steel particles in the filament don’t add a lot of strength in comparison to continuous fibers.
*how to make epoxy molds with added carbon fiber reinforcement*
Great, the end 20 sec.
Uh a new one :-D
Its still PLA on the Outside.. Better make a Mold out of PLA and make it from Real Epoxyd Carbon.
For the longitudinal screw part at the end of the video why not have holes at both ends of the screw, you can then thread the fibres through with a rod or 'needle' repeatedly so its like a bobbin and you have many parralel tow threads. You then cut the looped ends at the top and bottom, seal the cyclinder and pour in the epoxy.... You should be able to get a much denser 'infill' this way.
Btw. for bigger parts what about standard infil and load up those 'pockets' with chopped fibre + epoxy mix... I.e. the printed part walls becomes the mould for an internal 'forged CF' part: th-cam.com/video/25PmqM24HEk/w-d-xo.html
4:58 - I think you need to let the dog out :)
Suggestion : snip or grind the carbon Fibre into tiny Fibres (
They sell it like that
The coolest most important thing to me was the z strength and you didn't test numbers I'm so saaaad
3 years later and continuous fiber printing still sucks
you have the same accent like great Scott
wrong epoxy or just not fully cured
Epoxy may not cure as well inside a closed cavity. Locktite type materials might have better results. They are made to cure inside air tight spaces.
Totally wrong. Expoxy cures with the hardener mixed in, no air, humidity required, or any solvents to de-gas
we vacuum the epoxy into molds...
Die größte Belastung bezüglich Zug oder Druck tritt in der Hülle auf. Deshalb hat die Evolution hohle Knochen geschaffen. Bei so simplen Teilen wäre es also zweckmäßiger eine wiederverwendbare Negativ-Form des Objektes zu drucken (oder zu fräsen).
The greatest load in terms of tension or compression occurs in the hull. This is why evolution has created hollow bones. So with such simple parts it would be better to print (or mill) a reusable negative shape of the object.
Thoes steel s hooks...win!...😑
You can purchase carbon fiber that has been milled Into almost a dust form. You could then mix it into your resin and fill your parts with that. You must use the vacuum. Your syringe method is very flawed. Also you can purchase carbon fiber in a braided form that could be inserted into your part more easily than a simple tow which is what you are using now. Lastly,I different is epoxy would work better. The cheap stuff that you buy on Amazon it’s too slow to cure. The faster any epoxy cures the harder it will be.
Wennnnnn das schreckliche englisch nicht währe ....
Ja, es wäre schön wenn deutsche youtuber auch deutsche Videos machen könnten, davon gibt's nicht so viele vernünftige im maker Bereich
can people say "inexpensive"
'
Heavy German accent sounds super horrible but the video was good =)