Re: Re: carbon VP hub data?
You are correct Leo!
If you want to be put on the list for a sample, send me an off list email.
I'm located in the Netherlands. The material is produced in Switserland.
Best regards,
Kevin
2013/3/6 Leo Pilachowski <leop_at_lyradev.com>
> **
>
>
> Kevin,
>
> Thanks for the info. For some reason my postings sometimes have characters
> left out. I wrote 1/2 oz/sq.yd. for your 17mg/m2 but it was saved as 1
> oz/sq.yd. Also, the 2cm tape we can get in the US is 1.1 oz/sq.yd. and that
> number got left out, too. Many people use the term unidirectional fabric
> for unidirectional carbon. It may be technically incorrect but it is
> descriptive. Besides, often, the unidirectional carbon does have
> perpendicular binding fibers.
>
> So, in what country do you reside and where did you obtain the light
> weight prepreg? If you ever buy more, I would like to get some, too.
>
> Thanks,
>
>
> Leo
>
> --- In Indoor_Construction_at_yahoogroups.com, Kevin Lamers wrote:
> >
> > 17g/m2 is about 0.5oz/sq.yd.
> > This is excluding resin. With resin it is about 28g/m2 (about
> 0.8oz/sq.yd).
> > The material is indeed unidirectional so you are free in choosing the
> fibre
> > direction. Obviously it is no fabric since all fibres run in one
> direction
> > (see picture).
> >
> > The prepreg is stored in a freezer, that way it will be good for some
> > years. At room temperature it will survive for about 2 months. Shipping
> > will of course reduce this time by a week or so.
> >
> > I made two types of tubes:
> >
> > One layer in the length of the tube and then wrapped with a 2mm wide
> piece
> > of prepreg in the hoop direction.
> > One layer in the length of the tube and then wrapped with thin dry kevlar
> > thread (there is enough resin in the first layer to impregnate the kevlar
> > as well).
> > The second being lighter of course.
> >
> > Kevin
> > Op 6 mrt. 2013 00:08 schreef "Leo Pilachowski" het
> > volgende:
> >
> > > **
>
> > >
> > >
> > > This carbon fabric is very light. Is it unidirectional fabric? Is the
> > > weight of the prepreg (17g/m2) with or without the epoxy. That is, is
> it
> > > just the weight of the carbon or does it include the epoxy? 17g/m2 is
> a bit
> > > under 1oz/sq.yd. In the US, we can commercially buy 1.5 oz/sq.yd.
> > > unidirectional fabric but(2 cm wide) unidirectional tape is rare at
> times
> > > and expensive.
> > >
> > > Also, how long did the prepreg keep? Did you refrigerate it?
> > >
> > > For light weight carbon tubes, have you played with wrapping individual
> > > tows or carbon?
> > >
> > > Leo
> > >
> > > --- In Indoor_Construction_at_yahoogroups.com, Kevin Lamers wrote:
> > > >
> > > > Hi Kang,
> > > >
> > > > The carbon tubes (both the spar and hub) are made of IM carbon (T800)
> > > > prepreg 17 gram/m2. The outline is made of UHM carbon (M60) roving.
> > > > I have checked the individual weights and they are as follow:
> > > >
> > > > Blade (outline+ribs+balsa spar+covering): 0.074 gram
> > > > Carbon spar (including aluminium bearing and actuator wire): 0.018
> gram
> > > > For 2 blades + spars: 0.184 gram
> > > > Hub: 0.078 gram
> > > > Total: 0.265 gram
> > > >
> > > > I now figure that I should half the length of the carbon spar and
> make
> > > the
> > > > balsa spar a little longer, to save some weight (and make the outline
> > > > thicker)
> > > >
> > > > I haven't had the change to fly it yet since I still have to build
> the
> > > rest
> > > > of the model. I have made some F1D's a couple of years ago, in the
> mean
> > > > time I was only doing F1B, and I figured it would be nice to give it
> a
> > > try
> > > > again. So here I am ;-)
> > > >
> > > >
> > > > Best wishes,
> > > > Kevin
> > > >
> > > >
> > > >
> > > > 2013/3/5 Yuan Kang Lee
> > > >
> > > > > **
> > > > >
> > > > >
> > > > > Kevin,
> > > > >
> > > > > looks very nice. What materials are the spar and outline made from?
> > > > >
> > > > > Have you had a chance to fly it ?
> > > > >
> > > > > -Kang
> > > > >
> > > > >
> > > > > --- In Indoor_Construction_at_yahoogroups.com, Kevin Lamers wrote:
> > > > > >
> > > > > > Hi Mike,
> > > > > >
> > > > > > I have to check tonight for the exact numbers, but by heart
> about:
> > > > > > VP (just the centre, not the extended carbon tubes): 0.08 gram
> > > > > > 2x blade + extended carbon tubes: 0.185 gram
> > > > > >
> > > > > > At least the total is 0.265 gram, see picture.
> > > > > >
> > > > > > Best regards,
> > > > > > Kevin
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > > 2013/3/5 mkirda_at_
> > > > > >
> > > > > > > **
> > > > >
> > > > > > >
> > > > > > >
> > > > > > > Hi Keven.
> > > > > > >
> > > > > > > What does the hub weigh minus the prop spars/outlines?
> > > > > > > And what does the entire prop weigh?
> > > > > > >
> > > > > > > The design is interesting to me mainly because I HATE tying
> kevlar
> > > > > > > hinges... LOL.
> > > > > > >
> > > > > > > Regards.
> > > > > > > Mike Kirda
> > > > > > >
> > > > > > >
> > > > > > > --- In Indoor_Construction_at_yahoogroups.com, Kevin Lamers
> wrote:
> > > > > > > >
> > > > > > > > Here a carbon hub I'm working on currently. The main tube
> weighs
> > > 15mg
> > > > > > > > including the bracket for the screws. The tube is 2mm ID and
> has
> > > a
> > > > > 0.05mm
> > > > > > > > wall thickness (2 layers 17 gsm prepreg).
> > > > > > > > I hope the attachment gets through.
> > > > > > > >
> > > > > > > > Kevin
> > > > > > > > Op 1 mrt. 2013 21:13 schreef het volgende:
> > > > > > > >
> > > > > > > > > **
> > > > > > >
> > > > > > > > >
> > > > > > > > >
> > > > > > > > >
> > > > > > > > > I vote that you show all of us your unproven hub so we can
> all
> > > > > pick it
> > > > > > > > > apart before you perfect it.
> > > > > > > > > On a personal note, all this talk of carbon, kevlar &
> > > fiberglass
> > > > > has me
> > > > > > > > > thoroughly confused. I need pictures.
> > > > > > > > > Gary Hodson
> > > > > > > > >
> > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > >
> > >
> > >
> >
>
>
>
Received on Wed Mar 06 2013 - 08:01:32 CET
This archive was generated by Yannick on Sat Dec 14 2019 - 19:13:47 CET