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twissta
twissta
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First off i am excited about your website and applaud you on your information that you supply. As I have read your sites and the information over and over again there are some things I would like to clarify and confirm, before actual execution in ordering supplies.


I would like to make a carbon fiber (CF) heat shield to replace the metal one that covers the exhaust can on the bike..

My question are:

1) Is it necessary to have a autoclave to cure the part...after making a mold and laying the proper amount of CF using the High heat kit  products? what other method can I use, vacumm bagging? if so it will take some time too save up to order the entire kit. I hope there is an alternative?

2) Can carbon strips be used with pre-preg epoxy/resin and CF overlay....or wet lay application? Do the strips have a friction capacity or wear factor?
Let me clarify, I am an avid motorcyclist and racer, Now that I have found you guy's I would like to build my own parts for my bike, because I don't like the design or quality of what's out there..although I won't be getting this part done right away, I would like to do my research and converse with you guy's to help in this development.

I am developing an idea and the strip layied between the cf layers, would allow the thickness and support of the part, to cut cost  and give me the confidence that the part would work. because this part may hit the ground in a crash I want it to not wear through, which is for the purpose of the part....should it work I believe it will revolutionize the market for me and fellow riders/racers......

Can the strip be shaped or is it rigid?
what would I use to get a clean cut if I were to cut the strip heavy duty and the other thickness's...a ban saw? what kind of blade.

I know it's allot to start off with, however that's what this site is for and yes I am going to start with a simpler mold/part to get an idea of how your system works. the reason for these questions and answer's are for the final decision in to buying the basic kit or buying the bulk products to build more than one product at a time. I am also aware of that there will be trial and error along the way.....this is why I am leaning more towards the bulk molding, resin etc.......trust me guy's this won't be the last conversation we will be having. I want to thank you in advance and please have patience..I have some fiber glass experience so I am not oblivious to the methods. Truly your products, methods and info. are far more superior than what's out there, or at the least, much more user friendly......


Now for the first project question?

It looks like I will need to buy the separate products (epoxy gel coat/resin) etc..  to build a "carbon Fiber" front fender for my bike due to it's size, correct? Are there any tips you can provide me with as well...

Understanding it's a rather large part vacum bagging would probably be ideal....however don't have 500.00 dollars right now but saving...I am also building my race bike so you know what that cost......

I hope I have posed my questions or began to paint a picture that is easy for you to visualize as to what I am attempting to achieve.

Thank you in advance,

Martin (Twissta...throttelman....!) say it fast and it will make sense LOL 
Edited 13 Years Ago by twissta
Matt (Staff)
Matt (Staff)
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Hi Martin,

Welcome to the forum (even before we've told anyone about it!). I'm glad you like what we do Smile.

Answers to your questions as follows:

1) Is it necessary to have a autoclave to cure the part...after making a mold and laying the proper amount of CF using the High heat kit  products? what other method can I use, vacumm bagging? if so it will take some time too save up to order the entire kit. I hope there is an alternative?


It's certainly not neccessary to cure the part in an autoclave - autoclaves really are reserved for pre-preg carbon fibre (and even then there are some pre-pregs that don't require an autoclave). Depending on the shape of your heat shield mould you might be fine to wet-lay it (i.e. no special process at all, just dry carbon and brush application of wet resin) or, if the shape of it is more complicated, it may be neccessary to either use a process like vacuum bagging/resin infusion or you might just be able to get away with a little 'manual assistance' to keep the carbon pressed firmly against the mould's surface whilst it cures. By 'manual assistance' this could be something as simple as putting release film on the inside of the part after wet laying it and then pressing car sponges into the mould (and holding them there somehow) to keep some pressure on the laminate whilst it cures. This prevents the carbon from coming away from the surface (creating bridging and voiding) whilst it cures.

When working with any 'High Temperature' epoxies what you will certainly need to do is 'post cure' the part before you use it. Post curing is where you gradually heat the part up to at least its future operating temperature, thereby fully curing the resin and realising the best mechanical performance (and high HDT - Heat Distortion Temperature). Put simply, this means that if you make your heat-shield, once it's cured fully in the mould at room temperature you would leave it in the mould and put the mould somewhere very warm (40 degrees) for maybe 12 hrs and then, still in the mould, get the temperature up to 70 degrees for a few hrs. You would then demould it (so that you don't need a mould that can take very high temperatures) and then put the part in an oven and the gradually ramp the temperature up to 180 degrees C. This type of post cure would ensure that the next time the part is at 180 degrees (when it's on your  bike for example) that it won't be affected at all by the heat.

2) Can carbon strips be used with pre-preg epoxy/resin and CF overlay....or wet lay application? Do the strips have a friction capacity or wear factor?


If I understand you right by carbon strips you're talking about ready-made pulltruded carbon fibre strip (i.e. a finished, cured product) and then laminating carbon fibre and resin around these strips in some way? - If so this should be perfectly possible although I'm not clear on what specific advantages this would bring over just laminating all of the reinforcement from cloth and resin (rather than including some ready-made strips) but I can imagine there are certain applications where this could have its merits.

because this part may hit the ground in a crash I want it to not wear through, which is for the purpose of the part.


If you're looking for abrasion resistance or impact strength then you should certainly consider Kevlar as an alternative to carbon (or in conjunction with carbon). Kevlar has a much higher elongation-to-break strength than carbon and so is very often used for crash protection/abrasion protection etc. Skid plates, undertrays and track car bodywork all often contain kevlar as some or all of their reinforcement. You work with it in just the same way as you would carbon.

I don't quite know what you've got in mind for this part but another option to consider if you're looking to reduce friction in the finished laminate would be the addition of graphite powder to the resin, probably only as a coating layer. Graphote powder is a naturally low-friction additive that combines well with epoxy to make a low friction coating (often used on the runners on the underside of a boat hull for example).

Can the strip be shaped or is it rigid?
what would I use to get a clean cut if I were to cut the strip heavy duty and the other thickness's...a ban saw? what kind of blade.


Pulltruded carbon fibre strip is very much rigid and can't be reformed/reshaped. To get a clean cut you're better off using a slitting disc rather than anything with teeth (like a bandsaw blade) - the type that you would use in an angle grinder. If you do use something with teeth then ensure the teeth are as small as possible (metalworking size not woodworking size!) as this will reduce the chipping effect the teeth have on the carbon.

It looks like I will need to buy the separate products (epoxy gel coat/resin) etc..  to build a "carbon Fiber" front fender for my bike due to it's size, correct? Are there any tips you can provide me with as well...


Making the mould for a front fender for your bike would be possible using our Large Epoxy Mould Making Kit but epoxy tools (moulds) are the mould expensive of your options for mould making. Since you have other plans to make parts I and you also have some fibreglassing experience I think the best mould making system for you would be our new Uni-Mould system. We've launched it for just such projects - it's lower cost than epoxy, can operature up to 90 degrees C (great for post-curing your heat-shield), is compatible with epoxy/polyester/vinylester resins (you'll be using epoxy of course) and, like epoxy, it's zero shrink.

Rather than repeat it all here, please take a look at our
Introduction to Uni-Mould and Application Guide to get a good idea about the system. Since you're based in the 'States you could save shipping costs by buying the Uni-Mould resins from us and then sourcing the Chopped Strand Mat locally.

I nice starter pack for the Uni-Mould system would be something like:

*Small Pack*
1kg Uni-Mould Tooling Gel-Coat
1kg Uni-Mould Coupling Coat
5kgs Uni-Mould Tooling Resin

*Medium Pack*
5kgs Uni-Mould Tooling Gel-Coat
5kg Uni-Mould Coupling Coat
10kgs Uni-Mould Tooling Resin

As for making the part itself, you're right that ideally we would probably be suggesting vacuum bagging or, better still, resin infusion for making something like this. That's not to say that it couldn't be wet-laid but you'll certainly have to deal with issues of the carbon bridging in corners and your surface finish is not going to be as good as if you'd used resin infusion. If you can stretch to it then you would find the resin infusion process very rewarding and if you progress to doing other parts for the bike, like fairing panels, then a process like infusion will become essential rather than just recommened.

If you decide to wet-lay the fender then have a practice run on something smaller first so that you know what to expect. Use 200g 2/2 twill cloth (it will be the easiest to work with in this way) and use the EL-2 Laminating Epoxy (it's amazing stuff which wets out carbon fibre incredibly well, reducing air entrapment etc.). Use a
bristle roller to get rid of any air bubles in the laminate (they work better than any other type of roller for this).

If you resin infuse it then go for a 200g 2/2 twill cloth on the surface and then maybe just a single layer of 660g 2/2 twill to back it up. This will bring your costs down quite a bit, heavier carbon cloth is much cheaper than multiple layers of lighter cloth. Use the IN-2 Infusion Epoxy and follow the instructions and process shown in our Resin Infusion Tutorial Video.

I hope this gives youa good starting point and look forward to working with you.

All the best, Matt



Matt Statham
Easy Composites / Carbon Mods - Technical Sales
twissta
twissta
Supreme Being (147 reputation)Supreme Being (147 reputation)Supreme Being (147 reputation)Supreme Being (147 reputation)Supreme Being (147 reputation)Supreme Being (147 reputation)Supreme Being (147 reputation)Supreme Being (147 reputation)Supreme Being (147 reputation)
Group: Forum Members
Posts: 27, Visits: 341
Ok bro, gotta think this one through then, on the front fender....Might do the rear fender first, since it is smaller in size and probably would be easier for my first project. Read and re-read for (understanding) your response before I bombard you with more questions,


Thanks again,
GO

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