Milled Carbon Fiber....chopped carbon and kevlar...

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I am not interested in powder personally. Now if it were chopped 1/16" to 1/4" I would interested.
 
What would the pricing be on chopped fiber?
Can you ship internationally? If so what would roughly 500g (1 lb) of product to Australia cost (100g milled, 400g chopped)
 
Still working on pricing and shipping...but the goal, to be a steady quailty supplier of the 3 products.
Right now I'm working with 17.2kg packages of the 3
Also including milled fiberglass...as a 4th product.

Maybe about mid August, should be all broken down, packaged, priced, ready to ship. Just want to see if there is enough intrest to move forward.
 
Chopped Kevlar, and carbon. Yes, figure out pricing as those I am interested in.
 
How does 4-8oz squeeze bottles with caps sound for the milled carbon and fiberglass?
How does small 1/2 pint - 1 pint paint cans sound for the chopped carbon and kevlar?

Also the heavy duty syringes that you can wash out and reuse, disassemble etc.
 
I might be interested... Both in the chopped carbon and the Kevlar. A nice mix of the two would be great. Milled carbon could be helpful too. Syringes are good, I'd probably add a few to an order.
 
I am not interested in powder personally. Now if it were chopped 1/16" to 1/4" I would interested.

I believe Mark's comment, which was just passed over, was in regards to the fibers being too small to make a difference in bonding. As I understand it from a previous thread if the chopped fibers are too small then they will not provide any appreciable benefit, strength.

Does anyone know what "too small" or the "right size" is?
 
I believe Mark's comment, which was just passed over, was in regards to the fibers being too small to make a difference in bonding. As I understand it from a previous thread if the chopped fibers are too small then they will not provide any appreciable benefit, strength.

Does anyone know what "too small" or the "right size" is?

You are correct- the strength comes from the fibers being in a matrix of adhesive/epoxy. If too short the fibers likely cannot spread a load out so to speak.
 
That's funny you mention it, as I recently began using single tows of CF for things like strengthening seams.

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The tip of this cone I made today is balsa, but with 2 scrambled up tows of CF for reinforcement so that it can be pressed into a bearing for turning without deformation when that step comes, then precisely tuned in, and will be durable without adding weight.

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I'm no longer interested in making CF look pretty, but instead just using it for structural support and light weight as it was intended.
Most of my CF stuffs will be hidden from view from now on, to allow me to only use it where it is needed.
 
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That's funny you mention it, as I recently began using single tows of CF for things like strengthening seams.

My understanding is the strength in any cloth is in the direction of the fiber. Think of the lines of CF as the grain of wood. If using uni-directional cloth on a rocket, for the tube it would go lengthwise. For fins, doing tip to tip perpendicular to the body tube to reduce fin flutter.

I can't say that what you are doing is not helping, but ideally you would span the joint with a bunch of shorter threads.
 
In my experience with these materials,
1/4 chopped carbon fiber tow is best all around for mixing with almost all types of epoxy for structural and load areas

Milled carbon, in its best purity, is exceptional for bonding and shear areas

Milled kevlar is awesome....heat, impact and shear properties. Leading fin edges or laminating?


Chopped kevlar, doesn't really exist in the way chopped carbon does. Chopped Kevlar/aramid falls apart, as the tows are no longer kept in place by length, when chopped. What you get is this cotton candy looking pile. Not really a bad thing if that is what you need. In order to get chopped carbon to stay together a light binder is applied that holds the tows together and usually applied on one side....

Any how it is difficult to make, bind and cut.

Carbon is no joke when you look at the COH bond in epoxy, sprinkle a bit of it or milled fiberglass with any and every batch, try it the next few mixes.
 
My understanding is the strength in any cloth is in the direction of the fiber. Think of the lines of CF as the grain of wood. If using uni-directional cloth on a rocket, for the tube it would go lengthwise. For fins, doing tip to tip perpendicular to the body tube to reduce fin flutter.

I can't say that what you are doing is not helping, but ideally you would span the joint with a bunch of shorter threads.

I understand that, so it is why I atleast break up the tows a bit so that the individual fiber cross each other here and there, and in the cone seam, I used that metal piece off of one of the worthless paper dust masks to open the tows and get them stuck to the FG wall fabric before injecting the minimum amount of epoxy necessary, (which I can now do thanks to you turning me onto those pipettes and graduated mixing cups.:)Those things are my new "Go To", and perfect for not wasting anything at the scale I typically work at. No mess either!!!).
The cone is 4" and will be foam filled after attachment to the aft section via a series of flow holes, but pre-foam weighs 16g., which is still less than my 2.6" tail cones typically end up weighing using conventional methods, so I'm on the right track. The inner wall is clear so that I can see how well the foam gets to everything and not have to make guesses.
On the nose cone the two tows are "Scrambled together", and there for hardness only, not any kind of structural support.
When the turning part is done, I will actually remove as much of that mess as I can to make way for the pointy tip, which fits fine over it, but it does not need to be there at that point.

Shredded or milled would have been ideal for either of these applications, better than my quick fix of course, but with none on hand, I did what I could. Typically, when I cut cloth outdoors, these things are produced as a by-product, but I do not collect them, as I have not research their handling characteristics yet, and since they are lightweight and float around in the air, I prefer to have them blow away from me.

I recently got a few panels of peg board, and am going to be building a sanding table like sodmiester uses, with a dust collector, and then I will be able to have shredded this and shredded that, which can be allowed to settle, then collected safely.

I would buy Rob's product, as it would be useful to a high degree, but I'm on a tight budget right now, so I'll simply make a note on my materials research and acquisition folder to get some when possible.

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The tissue on my SA-5 tail cone booster ring assembly was only there to absorb excess epoxy, and was removed once it had done that, and not there as any kind of structural anything. I just did'nt need any excess once the fabrics were in place, so why leave any?
 
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I got to take some pics of the material as I was examining and getting a control weight/volume on the product. More to come...


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1/32 milled S fiber glass. Mix with epoxy/resin for all around strong strength and thickener. A little goes a long way.




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Milled Kevlar(R) which has the texture almost like recycled paper? Virgin 12K Kevlar tow chopped and milled with no binder. Mix very well with epoxy/resin and it suspends in the matrix. Also can mix with a few drops of acetone or alcohol to suspend and add to epoxy/resin. Very high strength and torsion, also works well as a thick paste for high shock or heat areas.



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This is 1/8in. chopped carbon fibre. Virgin 6-12k tow with a polymer binder and cut. Wide uses, Very Strong. High Tension and load areas. Mix with epoxy/resin.


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This is 1/4in. Chopped Carbon Fibre. Virgin 6-12k tow with a polymer binder and cut. Wide uses, Very strong. High load, tension and strength. Mix with epoxy/resin




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This is milled fiber. Absolute virgin carbon fibre tow with no binder, chopped then milled and milled. About 100microns. This is not made from scrap bound tow, cured sheet, recycled or trimmings. Super strong, very hard, high loads. Mix with epoxy/resin.


I have tried all of these with CA, 15 min and 30 min hobby epoxy, Laminating epoxy, structural epoxy and RocketPoxy and it works very well to help modify your adhesives and opens up many options. A Little goes a very long way and will last for several builds as all of it is higher volume then weight.
 
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Maybe all it needs is a clever name like, Carbo-Sil
It certainly does look quite like something worth having.
 
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Also looking at making custom carbon plate and kevlar plates with different epoxies...is there a need for custom plate or a more cost effective, controlled sheets?
 
Also looking at making custom carbon plate and kevlar plates with different epoxies...is there a need for custom plate or a more cost effective, controlled sheets?

CF plate is wonderful stuff but very costly. We have gotten ours from a company called Protech Composites out of Vancouver, Washington.

https://www.protechcomposites.com/carbon-fiber-plates/

"Dragonplate" is another major retailer.

https://dragonplate.com/mobile/

I'm sure that if you can produce a quality product for a reasonable price it will sell.
 
First offering is almost ready! More material on the way, 30cc syringes are in too, tapered offset tip, cut to size. I am impressed with the quality of the material and the manufacturer.

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Also working on a double sided matte finish 12x12 carbon fibre, carbon/Kevlar, hybrid caul plate. Either prepreg OOA, or Infusion, with high temp moduls. epoxy. Still a few months out on that, possible CNC cutting of the material as well.
 
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Just used some of the chopped CF in this knife handle that is made up of CF. I wanted a unique finish, and sprinkling some of the chopped stuff as the last layer before clear coat really makes it unique IMO.

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Usually double gloss requires a heavy press on the plate.
It is possible with out a press. Also have seen some that were 2 sets joined, gloss on each side. Depends on the source.
 
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