Kite manufacturers+ aluminum foils

[tkettlepoint]

There is more carbon in a foil then there is in a bike frame. Bike frames hollow with 2-4 layers depending on location.. A bike frame would use about 3'x50"wide plus maybe a tiny bit more if you are pushing it.

Carbon foil for the most part is solid carbon. There are some out there that use fillers such as fiber glass , wood, high end foam.

both are about the same time to build

I use 10'x50" wide of different types of carbon per foil ( full set Wings , fuse, strut) And that is solid carbon.


just my 2 cents

Terrie

...aluminum over carbon.

More profit (bottom line) ?

I doubt there is more profit in alum product. Bicycle carbon frames can be easily found for <$500, and hydrofoil is not more costly to produce than bicycle frame. So, $1500 carbon hydrofoil is likely to be more profitable than $1000 alum foil.

[tkettlepoint]

right on the nose.

Price difference is huge, all you need is basically a sub $2k extrusion tool that gives gets you masts at approximately $20 per. meter. cut and finished if you use the best alloy available from most standard suppliers. Then you get the fuselage cut from standard tube sections and the adapter for the board which cannot be more than perhaps $40 if ordered in +100 quantities.

After this is done the two wings will probably be the main expense at about $50 milled in G10 depending on what specification you want. So that is $110 ex. handling and painting. Surface treatment and painting is probably another $20 and shipping plus handling $20. That is $150. If you are doing prepreg or even simple wet layup you will have spent more than that on mats(+resin) alone.

Wet layup in China with unknown quality of the fibers an resin might get you close, but you will of course have sacrificed a lot of longevity and stiffness along the way, which is probably why it is believed that a aluminum foil is better for the low-end market. Even the worst aluminum alloy has about the same stiffness as you will get from an average laminate and since hydrofoils are predominantly stiffness limited designs aluminum is a good solution, only penalty is weight.

Starting up a production in CFRP requires more big tools and these are quite expensive.

[windmaker]

Very interesting. True most big brand bike frames (including Colnago, Pinarello, Trek etc) are made in Asia and naturally the price difference between the one made over there and the ones made in Europe/US is significant.

Looks like a alu foil that costs roughly 150 euros to produce is sold over 5x that price, I would guess 2 or 3 times the production price for a carbon wherever it is made.

[Starsky]

$150 production cost?! I bet that's a bit of a low ball.

[FrederikS]

If they are paying more for it manufactured in China they are getting robbed, but you have to add some amortization on tools, startup costs and perhaps some extra handling fees if the numbers are low which I would suspect they are for hydrofoils. Average cost for 100 units all things considered is probably USD200-250, which gives the desired margin for a USD600-800 product.

This is based on the volume of the milling, price of tool and extrusion die.

If you want to do a cheap fuse/mast combo in CFRP you could do it in a single RTM shot, with in-mold inserts. Same goes for wings, the tooling cost would be higher than for pre-preg but if you can move 200+ units it begins to look alright. Assuming your benchmark is quality pre-preg like Taaroa.

[Bille]

I never understood the logic people use, when they decide on pre-preg ; the stuff is
expensive and you can make your own for WAY cheaper !! If your part cures at a High
temperature like 250 - 300deg-F ; the pot-life can be a few weeks, at 77deg-F , and
way longer if it's refrigerated, (months longer). If your trying to save money as a producer
of composite parts ; then make your own pre-preg, (it ain't that difficult).

Bille

[tkettlepoint]

Billie you are right. Wet prepreg is the way to go.. The resin I use is heat set at 180 for 60mins. and lets just say sanding isn't fun after you pop the part from the moulds.


Terrie

[Bille]

What kind of pot-life, (@77-deg F) ; do Ya get with that Terrie ?

Bille

[ROLAVI]

I thought this vid was cool and gave me appreciation for the effort to make a one off foil/foilboard.

https://vimeo.com/136474166

[FrederikS]

I never understood the logic people use, when they decide on pre-preg ; the stuff is
expensive and you can make your own for WAY cheaper !! If your part cures at a High
temperature like 250 - 300deg-F ; the pot-life can be a few weeks, at 77deg-F , and
way longer if it's refrigerated, (months longer). If your trying to save money as a producer
of composite parts ; then make your own pre-preg, (it ain't that difficult).
Bille

Pre-preg is the easiest way to go if you want consistent performance. Making your own limited process control will not give you that, plus the resin you can source on the market is of a very different composition than what most pre-preg companies with proprietary resins systems are using. Pre-pregs are still a good compromise for low volume high performance parts because the tools needed are simple. The real issue is cycle time for mass production but you do not really do that with pre-preg unless it is the only way to make them. Of course the tools are cheapish so you can double up but then the autoclave capacity can make it hard to push out enough parts.

The price is not that horrible when you buy 100 m or more at the time. Roughly 2x the cost of fibers plus resin for VIP. Another downside is that you get a limited option in terms of mats, the selection so limited which makes pre-preg a bit annoying when optimizing layups.

If you can just commit to selling 200ish foils a year you can do high end RTM, which if you know what you are doing will perform just as good as a pre-preg one. This will give you very cheap parts that are very consistent in terms of performance.