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Composites/questions and answers - 1/4/2003 1:15:58 PM   
ace2002


 

Posts: 73
Joined: 1/4/2003
From: petaluma, CA,
Status: offline 		Iv'e been posting to all your questions about Composites and now Im going to post a place to call, my fingers are getting tired of posting, you all can call me at
Advanced Composite Engineering here in California
(707) 762-6542
There seams to be a lot of confusion and questions that are best answered on the phone, so you need to call and describe all your troubles. Iv'e been doing this for 20 years now, hell I built the first F117 stealth plane prototype, I know Composites well
Mike
       Post #: 1

Composites/questions and answers - 1/5/2003 6:13:15 AM   
ace2002


 

Posts: 73
Joined: 1/4/2003
From: petaluma, CA,
Status: offline 		Here is a helpfull chart on the understanding of Composite Materials. Remember that "all cloths are not the same", the ones that are not woven are called; "Unidirectional" and are much stronger than the woven types. "A crow foot weave is the standard type used in the industries", then you get to other types that have the type 3-4 over- 1 under, this is much stronger.
I use the best S-2 cloth 6 oz. that Hexall has, its costly but good.
Use this list as a base line, to find the best lay-up of your part.

Advanced Composite Engineering
Best<------------------------------------------------------------------worst

Cost: E-Glass, S-Glass, Kevlar, Graphite, Ceramic

Weight : Kevlar, Graphite, S-Glass, E-Glass, Ceramic

Stiffness : Graphite, Kevlar, S-Glass, Ceramic, E-Glass

Heat : Ceramic , S-Glass, E-Glass, Kevlar, Graphite

Toughness: Kevlar, S-Glass, E-Glass, Ceramic , Graphite

Impact Resistance: Kevlar, S-Glass, E-Glass, Ceramic, Graphite

Resins types : Aero space epoxys, marine grade epoxy , vinyl ester epoxy, Iso polyester, General-purpose polyester

Cores: nomex honeycomb, nida-core honeycomb, foam core, metal core, wood core

Often the choice of the materials to use for a laminate is difficult because of the required properties. One must consider the advantages of one material over another and its anticipated performance. S glass is about 30% stronger and 15% stiffer than E-Glass. It has 20-25%of the stiffness of graphite and is as strong, but it is also 30% heavier.
S-Glass though, has only half the strength and stiffness of Kevlar and
twice the weight. Kevlar on the other hand, is 40% stronger and 25% lighter
than graphite but has only half the stiffness of graphite. Sometimes, blending different advanced composite fabrics in a laminate can achieve the proper balance of stiffness, strength and weight. Use the following parameters listed here, from a best to a worst case, to help you decide which advanced composite fabric(s) is best for your application. Also different types of resins will add to strength and stiffness and should be considered in the composite structure design.

Advanced Composite Engineering
Home of the:
AQUALITE Flying Boat
1010 Lakeville St. Suite B-3
Petaluma Ca. 94952
(707) 762-6542 ICQ #173948770
Mike Doughty E-Mail:ace2002@attbi.com

< Message edited by ace2002 -- Jan 6 2003 4:56AM >

(in reply to ace2002)
       Post #: 2

Composites/questions and answers - 1/6/2003 9:47:11 AM   
ace2002


 

Posts: 73
Joined: 1/4/2003
From: petaluma, CA,
Status: offline 		I have givin you all advice on Composites as best as I can, so please use this forum to ask as many people about your problems your having, 5 advices are better than one. If you all can't get the right advice on your projects, and still need the answers, post to this thread, and I will check in every so often, and try to answer them. I work full time in my shop, and dont have the time to come in here and check everyday. Weekends Im posting my car for sale.. anyone want a 67 GTO??
Mike

(in reply to ace2002)
       Post #: 3

Composites/questions and answers - 1/7/2003 1:08:33 PM   
shupack



Posts: 391
Joined: 9/30/2002
From: Omaha, NE, USA
Status: offline 		I'd love a GTO, trade you a topflite corsair 60" for it

I apreciate the info you've put in here, it's somthing i want to learn more about, need a UK distributor?
Dennis

_____________________________

Aoccdrnig to a Cmabrigde Uinervtisy sudty, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tih

(in reply to ace2002)
       Post #: 4

Composites/questions and answers - 1/7/2003 9:47:23 PM   
sayno2glo


 

Posts: 29
Joined: 1/2/2003
From: helsinki, FINLAND
Status: offline 		Ace2002 Great list!
I would like to ask few things.
Why wood core is worst? All the best molded planes has balsa core not Rohacell etc. foam core becouse balsa is more durable and easyer to do (it sucks less epoxy). I allso think that there is no big difference with marine epoxy and Aero grade. I have used SP-systems epoxy what is very good but it hasn't that PRICY Aero space name on it.

/Antti

(in reply to ace2002)
       Post #: 5

Composites/questions and answers - 1/8/2003 7:55:23 AM   
ace2002


 

Posts: 73
Joined: 1/4/2003
From: petaluma, CA,
Status: offline 		Thanks All for the response's, first off on my posting of materials list is to explain the many uses of Composite Materials. This list is one of the many uses of these materials and there many functions in the Composite world.
The world I live in,Composites for "real Composite aircraft", do not use wood as a stiffeners in there lay-ups, however in this form you use this all the time in your building of models, I work with real race cars, and wood has no place in them. Wood is good in models, don't get the two confused.
I like to help people in need, Composites are the best materials to construct anything.
As far as the Epoxys goes: build cheap, you are making Models, not rockets. There are a lot of Epoxys on this planet, and they all have there Designed uses, West Systems is good for what your doing, it has no place in a rocket.
Thank You for understanding..
Post away.. leave feed back if you like.
Thank You all
Mike
Anyone want to buy a 67 GTO

PS: I just finished a Land Speed Human Powered Bike
the top speed this year was 80mph, on the first try with this bike was 68mph, this was the first time in 10 years of going, the owner/driver friend of mine made the 60mph club. The bike body is 14' long x 23" wide. All composite, kevlar/carbon/s-glass/honeycomb/ cheap epoxy.
The point I'm making: Make your choice of cloths do all the work,the Epoxy we used was not for this intention, I mean, we called the company and wanted some specks on there epoxy, we told them we were making a bike body and needed the specks, the phone hung up. They were terrified we were using casting resin for sculpters only, they were stunned. The point is the epoxy we used did not need to go into the oven to cure. We needed this to be stiff as a rock, and light weight. We had made three test panels out of different type Epoxys, and this was the cheapest and stiffest we could find, $14.00 per gallon.The body was the best thing on the track that weekend, its way out of there range as far as Composites go. We Need a rider... you got the balls to go 82mph and we win $25,000, sorry had it wrong not 10,000
Use cheap Epoxy's and make your choice of fabrics do all the work.
We used: $950.00 for carbon/$650.00 for kevlar/$450.00 for S-2 cloth/$150.00 for honeycomb/$184.00 for epoxys 6 gal/vacummed bagged the hole thing up..than had to paint it up pretty..
We had to get this right, no turning back now...3 weeks time from plug to finished part, no molds.., then off to the races we went..Battle Mountain Nevada. This year we will win that $25,000 and you all will have to go faster..
PSS: we made a mold for the clear plastic canopy so the driver could see, and vacummed in the plastic sheet using boiling water to soften the plastic, hell you dont need no stinkin plastics vacumme machines. Saved hundreds..
Go to... http://rotatorrecumbent.com/
for the pics. this body we made is not posted yet.
Mike

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< Message edited by ace2002 -- Jan 12 2003 1:06AM >

(in reply to ace2002)
       Post #: 6

Composites/questions and answers - 1/8/2003 1:50:43 PM   
gregalot


 

Posts: 2
Joined: 12/12/2002
From: Franklinton,LA
Status: offline 		How much for the goat?

(in reply to ace2002)
       Post #: 7

Composites/questions and answers - 1/8/2003 5:42:55 PM   
hayman



Posts: 134
Joined: 12/14/2002
From: privite, PA, USA
Status: offline 		PS: I just finished a Land Speed Human Powered Bike
the top speed this year was 80mph, on the first try with this bike was 68mph, this was the first time in 10 years of going, the owner/driver friend of mine made the 60mph club. The bike body is 14' long x 23" wide. All composite, kevlar/carbon/s-glass/honeycomb/ cheap epoxy.
The point I'm making: Make your choice of cloths do all the work,the Epoxy we used was not for this intention, I mean, we called the company and wanted some specks on there epoxy, we told them we were making a bike body and needed the specks, the phone hung up. They were terrified we were using casting resin for sculpters only, they were stunned. The point is the epoxy we used did not need to go into the oven to cure. We needed this to be stiff as a rock, and light weight. We had made three test panels out of different type Epoxys, and this was the cheapest and stiffest we could find, $14.00 per gallon.The body was the best thing on the track that weekend, its way out of there range as far as Composites go. We Need a rider... you got the balls to go 82mph and we win $10,000
Use cheap Epoxy's and make your choice of fabrics do all the work.
We used: $950.00 for carbon/$650.00 for kevlar/$450.00 for S-2 cloth/$150.00 for honeycomb/$184.00 for epoxys 6 gal/vacummed bagged the hole thing up..than had to paint it up pretty..
We had to get this right, no turning back now...3 weeks time from plug to finished part, no molds.., then off to the races we went..Battle Mountain Nevada. This year we will win that $10,000 and you all will have to go faster..
PSS: we made a mold for the clear plastic canopy so the driver could see, and vacummed in the plastic sheet using boiling water to soften the plastic, hell you dont need no stinkin plastics vacumme machines. Saved hundreds..

_______________________________________________

PICTURES! PICTURES! please, I would really like to see some of the work you do.

Bill

(in reply to ace2002)
       Post #: 8

Composites/questions and answers - 1/8/2003 10:26:40 PM   
ace2002


 

Posts: 73
Joined: 1/4/2003
From: petaluma, CA,
Status: offline 		Ok everybody, go out and buy this car please, I need to make a few bucks on the body's..

Go to http://www.downsengineering.com

and leave feed back please
Mike

GTO for sale in here...http://www.musclecarads.com/page3.html

Bike pics are.. http://www.rotatorrecumbent.com
the body is not posted yet.. soon

Other projects I had the opportunity to work on, go to
http://structure.stanford.edu/research.html#project7

Super Mileage Vehicles, I have made these too, for San Francisco State.
go to.. http://ideanet.doe.state.in.us/super/2002Supermail/082302/imsteanotice.PDF

no cars in this form..e-mail me and I will send ad, not in here they don't have cars here HEHE
Mike

< Message edited by ace2002 -- Jan 9 2003 4:18AM >

(in reply to ace2002)
       Post #: 9

Composites/questions and answers - 1/9/2003 3:20:17 AM   
shupack



Posts: 391
Joined: 9/30/2002
From: Omaha, NE, USA
Status: offline 		ace, I've heard of a few guys here in the uk using G-10 as a skinning material, in you opinion, is this better than glass over balsa? I don't know how easy it is, I havn't tried it yet.

_____________________________

Aoccdrnig to a Cmabrigde Uinervtisy sudty, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tih

(in reply to ace2002)
       Post #: 10

Composites/questions and answers - 1/9/2003 7:13:33 AM   
ace2002


 

Posts: 73
Joined: 1/4/2003
From: petaluma, CA,
Status: offline 		What is g-10?? I'm not a walking encyclopedia, please tell me what this is first..and what was its designed purpose! You building the next Space Station??

Is this what your referring too??
http://www.professionalplastics.com/
do a search for g-10
Mike

< Message edited by ace2002 -- Jan 9 2003 4:33AM >

(in reply to ace2002)
       Post #: 11

Composites/questions and answers - 1/10/2003 10:31:37 PM   
shupack



Posts: 391
Joined: 9/30/2002
From: Omaha, NE, USA
Status: offline 		oops. sorry, yeah, it's the stuff they make PCB's out of. large scale modelers have been using it to make accessories for ages (gear doors and hatches) but just recently it was mentioned in one of the mags how to get it in 3x4 sheets of .11 for skinning, no glassing over needed, but no-one knows any more about it, and the author of the article won't answer my e-mails so I can't find out how easy it is to work with. it's about 30$ a sheet in the uk.

_____________________________

Aoccdrnig to a Cmabrigde Uinervtisy sudty, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tih

(in reply to ace2002)
       Post #: 12

composites - 1/11/2003 4:45:13 AM   
Mike James



Posts: 2465
Joined: 1/19/2002
From: Anchorage, AK, USA
Status: offline 		Ace2002, Have you built any radio-controlled model airplanes using composites?


_____________________________

Mike James
RC Design and Building - www.nextcraft.com

(in reply to ace2002)
       Post #: 13

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Composites/questions and answers - 1/11/2003 7:01:48 AM