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@@chrisruf7590 You would be impressed by the strenght of forged CF, airbus in partner with Lamborghini studied it (or airbus gave the know how to lambo I don't remember, or was it boeing? lol) and made it work for a front suspension arm. Of course it was molded under high pressure not just hand pressed into the mold (edit: found it, it is pressed at 100-150 bars). But I remember giving it good strength/weight ratio and made it an isotropic material. Don't know why they choose to abandon it for use on mechanical parts ^^
@@MrEratrace That 100-150 bar is necessary that the fibers are well wetted with the resin to reach the break length within the resin. Still the random orientation doesn't help too much, as most the load here comes as bending, shear and normal force: filament winding can be optimized for these loads what result in extremely light but strong part.
@@beachboardfan9544 The final verion of their moulded tube connector, not the quick and dirty version shown in this video. They said that the final version is out of scope because most hobbyists wouldn't have the tools required to make it, but I suspect it's more about protecting their intellectual property regarding the process they used to create the final moulded version.
Why not just 3d print both halves out of ABS, vapor polish and apply mold release? You could also 3d print an insert with very sparse infill to reduce the carbon drilling and waste. you could make the final drilling operation a lot more fast and accurate by 3d printing a fixture to hold a drill guide. I regularly 3d print holders for #30 drill guides when I need an accurate bolt pattern. A few minutes in SW and then a hour of printing, drill #30 then step drill to final size, the results are usually pretty good.
Bill Judge That would work too! There are lots options for making molds. We ended up CNC cutting the production mold from aluminum. Thank you for watching!
Hans-Eirik Hanifl Thank you! Agreed that HDPE would be a good option. We used a machined aluminum mold for our production mold and HPDE would serve as a good middle ground alternative between MDF and aluminum. We recently started experimenting with 3D printed molds for prototyping too. Thank you for watching!
Great video. The key for fiber to add strength is fiber orientation. Random loading will not increase composite strength. and may even decrease strength. So what the end result may be just the strength of the matrix. ie. epoxy. Of cause part will be more dimensional stable, harder, and stiffer but no more stronger.
Thank you for this overview! This is a wonderful technique. On the production mold, did you use a ram (threaded or press activated) into one or more of the tube openings to essentially "forge carbon fiber" the end piece, or did you use the same open mold technique you used in this video? What you are doing is inspirational. Thank you for sharing your journey and techniques with us.
I would suggest looking into the easycompositestv channel. They recently (~3 weeks ago) did a HOW-TO titled "Make Forged Carbon Fibre Parts Using Compression Moulding" ...they are a manufacturing company/supplier and put out some VERY high quality how to's!
i would 3d print a t-shaped mandrel out of water soluble filament , covered it with CF vacuum bag it let it cure and then dissolve the core in water. easier stronger faster
I would think that locating-holes and associated pins in the mold will help put your mold bits back together and the assembled mold back into position on a drill press or CNC table.
Given how thick final part walls need to be to account for porosity etc, I wonder if an off-the shelf connector made of welded of 6082 or 6061 Al with 1mm walls would be lighter and stronger than this connector
I'm not exited about the structural properties of this part. How about a 2 piece mandrel , in the shape of a T, with appropriate tapers to permit extraction ( the leg of the T would have to intersect a machined hole in the top section, to allow that to be withdrawn) The part could then be laid up with carefully cut cloth , and then vacuum bagged - to allow the longditudinal strands to be in tension as much as possible (depends on are you loading the tubes rotary or linear) I really enjoy your channel. Kind regards from John Spargo in Cape Town
Could you have 3D printed your fitting mold right off, and 3D printed a 3 piece removeable core? Or you could remove the thermoplastic sacrificial core with a heat gun or use a molded wax core?
Could you share more information about the final version ? I'm looking to cast a part out of resin and carbon fiber powder but needs to be strong enough.I was thinking of pressure casting it in a pressure pot .What kind of mixture epoxy/carbon did you used?
Hey! We are working through some videos to release but after those we are considering putting one together for the final version. Thanks for checking out the channel!
It's been 9 months, it is likely that the final version of the tube connector is a forged carbon piece using a compression mould, this involves a mould machined out of aluminium and a way of apply pressure to the "entry" either with a hydraulic press brake or vice. Because you're using carbon fibre powder and not chopped carbon, I'd recommend that rethink your material of choice, I'd mix the ratio to reassemble a thick pancake batter, liquid enough to cast conventionally with a silicone mould
Will you be putting up the Advanced Molded Tutorial video? I'm from a university team and we're trying to use Carbon Fiber tubes in the Suspension of an off road robotic vehicle. We need to make connectors for a 130 degree joint between two tubes, and joint is going to be fairly structurally loaded. Also do you use only physical testing for parts like these? Or is there any finite element method
You could have used pipe within pipe for the inside diameter to avoid needing to drill excess carbon filler out later, all you would need to do afterwards is ream to tolerance and yer done.
Yes, we ended up having a 3D printed mold made and have been using that to do testing with. We are thinking about putting a video together for the advanced method coupler. Thanks for watching!
Bis you abresin Printer, and Print the mold in Resin, its high def and you can polish the mold to a glossy Finish. The Printer and some Resin ist Like 250 bucks and you can make a Lot of parts Out of it, that are Like from the factory.
Most laminating epoxies will work for this but the lower the resin viscosity the better. The addition of the chopped carbon into the epoxy makes the mixture into a thick paste so the more runny your epoxy is to begin with, the more carbon you can add to the epoxy before it gets too thick to add into the mold cavity.
How did you guys go about finding the best price to buy your carbon fiber fabric for the over all plane? Also was the carbon fiber for wings and fuselage pre preg carbon fiber or ?
We worked with a couple carbon vendors to find bulk carbon fiber. The carbon in the wings and fuselage starts as dry cloth and gets infused with epoxy.
Roshan, thanks for watching and the questions! The pink paste is bondo which can be purchased from your local hardware store or online. The black paste is a carbon fiber and epoxy mixture. The epoxies and carbon fiber we use are not public info at this time.
Thats a lot of work for a connector. Why not make two halves of molded carbon fiber that bond the two parts together. Could 3d print all the molds or at least the parts to make the molds. Then people can just trim out the connectors using drilling in the corners then a jigsaw for the flat parts.
I definitely picked the wrong material for my project. I just figured common Sense would tell you that they would have PVC like fittings to connect carbon fiber tubes. Go figure. I'll have to look for either aluminum or pvc.
I have a great suggestion on some carbon fiber tube connectors. You are reinventing the wheel. Rock West Composites has some fittings called CARBONNECT I have used them and they work great! Here is the link: www.rockwestcomposites.com/shop/connector-accessories/carbonnect
I know I'm late, but for anyone else who's later still, they use aluminium for the connectors, which is a no-no because of galvanic corrosion. I'm not saying it doesn't have its applications, but not for this project.
Why not make the tubes yourself?, create the tubes and joints on a sacrificial mould (like a low melt metal or foam that can be melted out), then roll wrap them with a combination of biaxial carbon cloth and a filament, you could then share the stress at the junction/joint all the way dawn the tubes.
get mavcoat release agent made in Anaheim California. google. That Luan wood is better at home depot, i they have it thick. You can also spray pva w/air-bush. l do that over mavcoat to sometimes for different parts. Some get painted, some do not. Painted parts come out of mold with primer awlgrip. velosRus.com
you got a nice looking plane overall but you better be checking the structural properties before you start making claims or finished parts remember your building a aircraft I'm little dismayed at the seemingly casual approach to this particular part you have spent so much time developing this aircraft don't screw it up now
Thank you for the comment Fred! Just to clarify, this style of tube connector is not suitable for aircraft use. This was stated at 13:40 in the video. This video was meant to demonstrate a manufacturing method for a non-structural, prototype connector. You are correct that verification of structural properties is critical which is why we put a lot of effort into physical testing. We have highlighted testing in our other videos and on our Knowledge Base on our website. Thanks for watching!
Why not machine that from 7075? Weight? Seems like process reliability and cost would make sense from 7075. I'll hook you up and send you one from 7075 to compare against molded carbon. Just tell me the tube size. 😁
Thanks for watching and for the comment! There are definitely a lot of different ways to make a tube connector. You could machine them out of aluminum. One concern would be keeping the aluminum electrically isolated which you could accomplish by wrapping the tube in fiberglass in area where the connector makes contact. Aluminum can also be a little trickier to bond to. The advanced molded connector is made from a mold where we can produce many at one time which is much quicker and more cost effective than machining each individual connector.
![[TH] 2024 PMSL SEA W2D5 | Fall | พลาดวันนี้ จะต้องเสียใจ](http://i.ytimg.com/vi/A5-Cuo12p6A/mqdefault.jpg)
For more composites related knowledge check out: www.darkaero.com/knowledge/composites/
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Thanks guys, amazing video! I just wanted to ask if there's a reason you didn't use a 3D printed mould instead of MDF?
Yo, this was a great tutorial. Thank you! I couldn't find the video where you test the part. If you haven't yet, please upload that one!
if you did not use a chisel to open that mold it would not crack
Filament winding around waxed tubes comes to mind first for me.
And likely stronger
@@chrisruf7590 You would be impressed by the strenght of forged CF, airbus in partner with Lamborghini studied it (or airbus gave the know how to lambo I don't remember, or was it boeing? lol) and made it work for a front suspension arm. Of course it was molded under high pressure not just hand pressed into the mold (edit: found it, it is pressed at 100-150 bars). But I remember giving it good strength/weight ratio and made it an isotropic material. Don't know why they choose to abandon it for use on mechanical parts ^^
@@chrisruf7590 MUCH stronger.
@@MrEratrace That 100-150 bar is necessary that the fibers are well wetted with the resin to reach the break length within the resin. Still the random orientation doesn't help too much, as most the load here comes as bending, shear and normal force: filament winding can be optimized for these loads what result in extremely light but strong part.
You never made the part two for this!
I'd be more interested in them doing a video on the process they use to manufacture the higher quality tube connector.
@@anonanon7278 Whats the higher quality tube connector?
@@beachboardfan9544 The final verion of their moulded tube connector, not the quick and dirty version shown in this video.
They said that the final version is out of scope because most hobbyists wouldn't have the tools required to make it, but I suspect it's more about protecting their intellectual property regarding the process they used to create the final moulded version.
@@anonanon7278 I think they under estimate hobbyist's, and, they're also stingy with their mfg ways that are outside of self advertisement.
Why not just 3d print both halves out of ABS, vapor polish and apply mold release? You could also 3d print an insert with very sparse infill to reduce the carbon drilling and waste. you could make the final drilling operation a lot more fast and accurate by 3d printing a fixture to hold a drill guide. I regularly 3d print holders for #30 drill guides when I need an accurate bolt pattern. A few minutes in SW and then a hour of printing, drill #30 then step drill to final size, the results are usually pretty good.
Bill Judge That would work too! There are lots options for making molds. We ended up CNC cutting the production mold from aluminum. Thank you for watching!
Because like he said, not every d.i.y.'r has a 3d printer in their garage.most have drill press etc.
Great video!!
Loving all these videos about carbon fibre, a video related to your wing structure, especially the inner structure, would be awesome.
thanks TH-cam form bringing me here and more importantly thanks for sharing that amazing technique.
It surprise to discover how much efforts are behind a single small piece of our aircraft!
Great job (as usual)!
Marco Pugliese lots of effort but this was a fun project!
Thank you guys. Waiting for part 2
I am addicted to your videos.
Good investment for woodworking is a set of forsner bits for making accurate holes.
Nice video. I would recommend using HDPE for the mold material over MDF for increased durability and surface finish.
Hans-Eirik Hanifl Thank you! Agreed that HDPE would be a good option. We used a machined aluminum mold for our production mold and HPDE would serve as a good middle ground alternative between MDF and aluminum. We recently started experimenting with 3D printed molds for prototyping too. Thank you for watching!
@@DarkAeroInc I understand, I was just trying to suggest HDPE for individuals trying to run a low run production. Keep up the great videos.
Hans-Eirik Hanifl roger that! 😁
You guys are awesome teachers. I was going to skip this vid, but it was definitely worth it!
Great video. The key for fiber to add strength is fiber orientation. Random loading will not increase composite strength. and may even decrease strength. So what the end result may be just the strength of the matrix. ie. epoxy. Of cause part will be more dimensional stable, harder, and stiffer but no more stronger.
I want part 2!
Great video. I would say that if you were to drill a 1/4” pilot hole all the way through, your spade bit would follow it straight the first time.
How much pressure can that take? I’m looking for something that can handle 10,000 psi.
Thank you for this overview! This is a wonderful technique.
On the production mold, did you use a ram (threaded or press activated) into one or more of the tube openings to essentially "forge carbon fiber" the end piece, or did you use the same open mold technique you used in this video?
What you are doing is inspirational. Thank you for sharing your journey and techniques with us.
I would suggest looking into the easycompositestv channel. They recently (~3 weeks ago) did a HOW-TO titled "Make Forged Carbon Fibre Parts Using Compression Moulding" ...they are a manufacturing company/supplier and put out some VERY high quality how to's!
I neeed a dark aero
i would 3d print a t-shaped mandrel out of water soluble filament , covered it with CF vacuum bag it let it cure and then dissolve the core in water. easier stronger faster
I would think that locating-holes and associated pins in the mold will help put your mold bits back together and the assembled mold back into position on a drill press or CNC table.
Given how thick final part walls need to be to account for porosity etc, I wonder if an off-the shelf connector made of welded of 6082 or 6061 Al with 1mm walls would be lighter and stronger than this connector
What about galvanic corrosion bro ?
sadly you cant easily combine those 2 materials. also i could imagine if the parts are 1% flamless they could be stronger than aluminum
A respirator for paste wax use?
I'm not exited about the structural properties of this part. How about a 2 piece mandrel , in the shape of a T, with appropriate tapers to permit extraction ( the leg of the T would have to intersect a machined hole in the top section, to allow that to be withdrawn)
The part could then be laid up with carefully cut cloth , and then vacuum bagged
- to allow the longditudinal strands to be in tension as much as possible (depends on are you loading the tubes rotary or linear)
I really enjoy your channel. Kind regards from John Spargo in Cape Town
Excellent !
Could you have 3D printed your fitting mold right off, and 3D printed a 3 piece removeable core? Or you could remove the thermoplastic sacrificial core with a heat gun or use a molded wax core?
is there any info on the better version that you don't talk about here?
Could you share more information about the final version ? I'm looking to cast a part out of resin and carbon fiber powder but needs to be strong enough.I was thinking of pressure casting it in a pressure pot .What kind of mixture epoxy/carbon did you used?
Hey! We are working through some videos to release but after those we are considering putting one together for the final version. Thanks for checking out the channel!
It's been 9 months, it is likely that the final version of the tube connector is a forged carbon piece using a compression mould, this involves a mould machined out of aluminium and a way of apply pressure to the "entry" either with a hydraulic press brake or vice.
Because you're using carbon fibre powder and not chopped carbon, I'd recommend that rethink your material of choice, I'd mix the ratio to reassemble a thick pancake batter, liquid enough to cast conventionally with a silicone mould
Will you be putting up the Advanced Molded Tutorial video? I'm from a university team and we're trying to use Carbon Fiber tubes in the Suspension of an off road robotic vehicle. We need to make connectors for a 130 degree joint between two tubes, and joint is going to be fairly structurally loaded. Also do you use only physical testing for parts like these? Or is there any finite element method
Can you surface stabalize mdf parts with resin using a vacuum tank ?
Do you have information on your more advanced process? Two-part aluminum female molds with a tapered two-part core and pressure to compact the fibers?
wish there was a video of strength tests of such parts compared to a 3d-printed parts of a similar design..
Are there any problems of electrolysis with carbon fiber aluminium as there is with carbon fiber steel
I know I’m late to the game here, but did you all ever do the part 2? Would be nice to see the follow up test video.
You could have used pipe within pipe for the inside diameter to avoid needing to drill excess carbon filler out later, all you would need to do afterwards is ream to tolerance and yer done.
Where can you find tubing that would fit one inside the other to graduate down from 20mm down to a 14mm? Can you do something like that?
Bravo!
marc joseph Thank you!
Seal the MDF with Oil-Based polyurethane. If you're into using PVA, it makes a difference on bigger projects.
Have you tried printing the mold?
Also, I'd love to watch the more complex method
Yes, we ended up having a 3D printed mold made and have been using that to do testing with. We are thinking about putting a video together for the advanced method coupler. Thanks for watching!
@@DarkAeroInc Are you still planning on doing that video mate? It would be so awesome to watch!
Bis you abresin Printer, and Print the mold in Resin, its high def and you can polish the mold to a glossy Finish. The Printer and some Resin ist Like 250 bucks and you can make a Lot of parts Out of it, that are Like from the factory.
WHAT ARE THE TOLERANCES
What type of epoxy would you recommend?
Most laminating epoxies will work for this but the lower the resin viscosity the better. The addition of the chopped carbon into the epoxy makes the mixture into a thick paste so the more runny your epoxy is to begin with, the more carbon you can add to the epoxy before it gets too thick to add into the mold cavity.
Hi can you show the advanced tube connector making process
Yes pleeeaaasseeeee. !!!
How did you guys go about finding the best price to buy your carbon fiber fabric for the over all plane? Also was the carbon fiber for wings and fuselage pre preg carbon fiber or ?
We worked with a couple carbon vendors to find bulk carbon fiber. The carbon in the wings and fuselage starts as dry cloth and gets infused with epoxy.
@@DarkAeroInc !..What vendors did you use? 2. Do you see fiber prices in the near future doping due to wide use growing?
whats that pink paste and then the black paste? can you put links to them please, thanks for sharing how to make this
Roshan, thanks for watching and the questions! The pink paste is bondo which can be purchased from your local hardware store or online. The black paste is a carbon fiber and epoxy mixture. The epoxies and carbon fiber we use are not public info at this time.
@@DarkAeroInc ok thanks❤️
be careful with that chisel 😱
It seems that your tech lacks the main trick 😄
Good job though … incredible efforts to get stuff being perfectly done 💪
can you show us how to bond aluminium honey comb to fibre? not your special process, but give us tips or a step guide, as I am hobbyist.
Use forstner bits. Cleaner and easier to drill. Those spade bits suck.
You use black resin or black gelcoat?
For this tube connector we used a combination of resin and chopped carbon. No gelcoat.
Omg... 2:57
What carbon fiber printer did you use
Have you tried the markforged onyx + continus fiber reinforcement printer?
Should have aligned the faces before drilling the clamping/alignment bolts.
This could be done in half the effort with 2 part silicone molds
Thats a lot of work for a connector. Why not make two halves of molded carbon fiber that bond the two parts together. Could 3d print all the molds or at least the parts to make the molds. Then people can just trim out the connectors using drilling in the corners then a jigsaw for the flat parts.
you need to take some advice from another TH-cam aircraft builder building scrappy
Whose cat meowed at 6:28?
frizzkitten 🤷🏼♂️😉
I definitely picked the wrong material for my project. I just figured common Sense would tell you that they would have PVC like fittings to connect carbon fiber tubes. Go figure. I'll have to look for either aluminum or pvc.
Sad that you don't want to show us the really good version :/
I have a great suggestion on some carbon fiber tube connectors. You are reinventing the wheel. Rock West Composites has some fittings called CARBONNECT I have used them and they work great! Here is the link: www.rockwestcomposites.com/shop/connector-accessories/carbonnect
I know I'm late, but for anyone else who's later still, they use aluminium for the connectors, which is a no-no because of galvanic corrosion. I'm not saying it doesn't have its applications, but not for this project.
Why not make the tubes yourself?, create the tubes and joints on a sacrificial mould (like a low melt metal or foam that can be melted out), then roll wrap them with a combination of biaxial carbon cloth and a filament, you could then share the stress at the junction/joint all the way dawn the tubes.
get mavcoat release agent made in Anaheim California. google. That Luan wood is better at home depot, i they have it thick. You can also spray pva w/air-bush. l do that over mavcoat to sometimes for different parts. Some get painted, some do not. Painted parts come out of mold with primer awlgrip.
velosRus.com
you got a nice looking plane overall but you better be checking the structural properties before you start making claims or finished parts remember your building a aircraft I'm little dismayed at the seemingly casual approach to this particular part you have spent so much time developing this aircraft don't screw it up now
Thank you for the comment Fred! Just to clarify, this style of tube connector is not suitable for aircraft use. This was stated at 13:40 in the video. This video was meant to demonstrate a manufacturing method for a non-structural, prototype connector. You are correct that verification of structural properties is critical which is why we put a lot of effort into physical testing. We have highlighted testing in our other videos and on our Knowledge Base on our website. Thanks for watching!
Why not machine that from 7075? Weight? Seems like process reliability and cost would make sense from 7075. I'll hook you up and send you one from 7075 to compare against molded carbon. Just tell me the tube size. 😁
Thanks for watching and for the comment! There are definitely a lot of different ways to make a tube connector. You could machine them out of aluminum. One concern would be keeping the aluminum electrically isolated which you could accomplish by wrapping the tube in fiberglass in area where the connector makes contact. Aluminum can also be a little trickier to bond to. The advanced molded connector is made from a mold where we can produce many at one time which is much quicker and more cost effective than machining each individual connector.
ฉันไม่อยากจะพูดนะแต่ถ้ามาคิดว่า 3 น่ะมันอาจจะพอ
Just use some duck tap 😂
you wasted more than half of the material
The material is cheap so no worries there. :)
have you never heard of a male guide?
How much do you charge?
Worthless video if you can't use it in life threatening builds
That's terrible...