cabon fiber pipes for ob?

[Jimmy Whitbeck]

Lets see any one know how or what is used to make them? as in resin and how many layer's of carbon, and is thare any thing special to know about them good or bad??

any help would be welcomed.

thank you Jimmy

 

[TimD]

It's a closely guarded secret! The guy won't tell me what resin it is.

 

[lohring]

Jimmy

I just built a carbon fiber pipe that we dyno tested on a modified Zenoah. It got hot enough to fail at the aluminum header connection. Nitro engines have lower exhaust temperatures so it might work better. I used five layers of 8 oz prepreg with an aluminum header connection and stinger. I vacuum bagged it over a foam core and cured it in an oven. Disolving out the foam was a big mess.

Lohring Miller

 

[Jimmy Whitbeck]

It's a closely guarded secret! The guy won't tell me what resin it is.

some one gotaa know!

 

[TimD]

I've heard Vinylester resin works OK but it's not the stuff that the C/F pipe I have is made from.

 

[Guest]

JIMMY , DO NOT WAST YOUR TIME UNLESS YOU ARE TESTING A PROTO TYP / it will delamanate with only 10 % fuel, MY BROTHER WAS OVER NASA IN FLA , HE SENT TO ME A GALLON OF THE SPECIAL RESINE THAT THEY USED TO GLUE THE CERAMIC ON THE RENTRY CAPSUL WITH , AND EVEN THAT WOULD NOT HOLD UP TO THE TEMPS, OF THE NITRO . BEEN THERE AND DONE THAT J. IRWIN

 

[GTR]

Hi Guys

There a couple of guys in Australia who make CF pipes - including a 21 size O/B pipe. These have been selling here for years and don't seem to have any problems delaminating. TimD has been using one for a few years.

GT

 

[Grimracer]

It can be done...

here is a link

http://www.bollyprops.com/mufflersus.html

And another

http://www.aeroproduct.net/pipes.htm

Grim

 

[TomMoorehouse]

this is what i read worked:

http://www.cotronics.com/vo/cotr/ea_ultratemp.htm #4460

 

[TimD]

JIMMY , DO NOT WAST YOUR TIME UNLESS YOU ARE TESTING A PROTO TYP / it will delamanate with only 10 % fuel.

Sorry Jim but I beg to differ.

As GTR has correctly stated I have been using the Gadjetcraft CF pipe with 50% nitro for years with no delaminating or burning whatsoever - in fact the pipe got harder after a few temp cycles. The type of resin is absolutely critical. This resin that is used seems to respond to heat in a positive way. Most resins have the opposite characteristic.

Also this pipe uses CF "sock" rather than CF cloth. The only thing I don't like is that they weep castor oil. Doesn't seem to affect it tho'.

Tim.

 

[Guest_Tony]

Hello there,

Just want to tell you that the CF outboard pipes are working great.

Mine comes from the below provider and I can tell you that I am really happy and I checked it after 5 months and there is no crack or whatsoever. Using 25% nitro

Really good product.

My pipe comes from:

http://www.fastelectrics.com/nitro.asp

 

[Bob Kensill]

From my own personal experience,heat is not the problem,it is erosion. The carbon fibers end up inside the engine,and we all know what that will do to an engine. Take a lesson from the musical instrument industry. If you want your pipe to resonate,make it from a hard,thin metal. BTW Aerospace Composites sells carbon-fiber "socks" that can be pulled over a wax mold and they also offer high temp resin.

Bob

 

[TimD]

Bob,

I can honestly say I've never seen any adverse wear or carbon in my engines.

As for resonance - I'm not convinced. My CF pipe performed as well as - if not better than a pipe the same dimensions made from thin metal using the Kavan prop test on a bench - the difference being the power dropped in the metal pipe the hotter it got - this was not an issue with the CF pipe. On water testing revealed the same result.

My CF pipe regularly 2 stages also. B) The metal one did not.

Oh yeah - these pipes are not made with a wax plug. I know how he does it - i've seen it done - but he asked me not to reveal it as he had invested a lot of time and effort into getting it right.

Tim.

 

[TimD]

pic

 

[Slideblues]

Lime Green Coupler........ Fashion Fau Paux :lol:

I ran that same pipe here in the states too, no troubles and like Tim said a two stagin mama, Should have kept it but I sold it to Billy R. to help him get dialed in,

Gene

 

[Jimmy Whitbeck]

I gess with all the fuss about carbon fiber. and not been able to so far find a resin for the pipe temps. i will just end up maching up some press dies. to make them out of metal!

i just thought it would be cool to have some thing that most don't have!

Jimmy

 

[Bob Kensill]

Tim

If you compared your carbon fibre pipe to an Irwin aluminum pipe,no wonder you didn't see a difference! The Irwin pipes are way too soft to begin with. As far as not seeing any erosion inside the pipe, take a look at the Grand Canyon,if cold water can erode rock like that just think what hot acidic fuel can do.

Bob

 

[TomMoorehouse]

has anyone tried the epoxy i linked / showed you guys? I was thinking about getting some.

 

[TimD]

TimIf you compared your carbon fibre pipe to an Irwin aluminum pipe,no wonder you didn't see a difference! The Irwin pipes are way too soft to begin with. As far as not seeing any erosion inside the pipe, take a look at the Grand Canyon,if cold water can erode rock like that just think what hot acidic fuel can do.

Bob

Bob,

The bench testing was done against a hand made pipe out of tin that had the same dimensions as the CF (the protos were made this way as they are easier to make / modify)

Testing against other commercially available pipes was done later and was not the results I mentioned earlier. Sorry if this caused some confusion..

Grand Canyon comment is something I wouldn't have thought of!

Tim.

P.S I guess I'm going to have to cut a pipe in half to find out if erosion is present. What a waste.

 

[Kevin_R_Clark]

Seems your fast eletric guy is closed down for the time being. Least that is what his e-mil said.