Carbon fiber or Carbon Kevlar?

[ironwigwam]

I have been thinking of making some covers and guards for my motorcycle streamliner  from stainless but now thinking  of carbon fiber to be more safety oriented. Should I be using just plain carbon fiber cloth or should I be thinking of using a carbon kevlar weave for items such as tire covers , chain guards and parachute guards to keep chains or tire chunks from damaging parachute tubes. I see what appears to be plain carbon fiber used on parts but there could be kevlar interwoven? Any one have any thoughts? Any suggestions.

[Speed Limit 1000]

Kevlar is better for "protection". Go to www.fibreglast.com good people and lots of good information. If you use kevlar do not sand to the fuzz you will have to reseal it with resin. Good luck post some build photos.
John

[1212FBGS]

i have molds for various chute tube sizes and several wheel tubs and wheel pants... i also have molds for chain guards as well as angles... i can make you parts with any layup schedule and materials you call out....  www.motorcyclebodywork.com
Kent

[maguromic]

Kent, Do you have any wheel tubs for a 21" and 25" tires?  I may make a special Bonneville tea blend for you.
Tony

[1212FBGS]

yep i sure do.... ill try to send a pix tomorrow..
kent

[whitehendrix]

yes, CF/kevlar composites exist and typically are used for laminated structural pieces. i worked with the #38  ADT-sponsored AudiR8 LMP900 back in '02 and they're constructed with that stuff. it's magic. 2 layers or so of plain 2x2 twill CF, a layer of CF/k a resin reinforced honeycomb and another layer or so of CF/K if i recall correctly.

i know i'm revamping an old post here, but still, not bad info to have.
 tensile on CF is over 800kpsi. a few layers should suit most needs.

[manta22]

I'm embarrassed to say how long it took me to learn how to drill holes that are in the right place and, if there are more than one, to line them up so the bolts/rivets, etc fit through those holes.

Here is the right way (for me) to go about it using my windshield clips as an example:

Locate the centers of the holes in the aluminum--measure, don't eyeball it. Center punch a starting place and drill a pilot hole in each place with a #30 drill. Place the aluminum clip in the desired place and hold it in position with masking tape or duct tape; using the pilot holes as a guide, drill one hole through the fiberglass. Put in a Cleco fastener to hold it tight and prevent the clip from moving out of alignment. If the clip placement looks OK, drill through the other pilot hole into the fiberglass.
You now have two #30 holes that line up perfectly but the holes need to be 5/16" for the Hylocks that I'll use. They have a very low profile head that won't disturb the airflow as much as a bolt. These are curious little gizmos-- they are intended for tightening from one side only. A nut is tightened on the threaded section while an Allen wrench is used to prevent it from turning. There is a hex socket in the end of the threaded section of the Hylock.
Use a step drill to enlarge the pilot holes to 5/16". A step drill is self- centering and creates a round hole, even in thin sheet or fiberglass. De-burr both sides of each hole and tap the Hylocks into place in the clip. I used an orbital sander to deglaze the aluminum and cleaned them with Toluene and painted then with a zinc chromate primer before installing the Hylocks. I'll probably paint them black later.
I now have two studs in the clip which line up perfectly with the holes in the fiberglass body. Yahoo!

Regards, Neil  Tucson, AZ

[willieworld]

http://www.landracing.com/forum/index.php/topic,5438.0.html                         willie buchta

[manta22]

I guess I put this in the wrong section  -- sorry, Neil  Tucson, AZ

BTW, Willie has an excellent tutorial on this subject. My technique isn't any better than Willie's-- just different.

[willieworld]

me too                           willie buchta

[Constant Kinetics]

www.carbonmods.com has do-it yourself kits, instructional videos, and a helpful support staff. Tell them what you're working on and they can recomend what will work best for you. Prices are very reasonable. Allow 1-2 weeks for delivery.

[Ro Yale]

Carbon fiber gives the stiffness. But it has a low shear strength. That's where kevlar is good. I like to build parts with outer layers of carbon fiber and a layer or 2 of kevlar. Then I have a piece that is both stiff and tough. I would make something like a chain guard using this type of construction. Hope this helps.

[tauruck]

Ro Yale is spot on with his advice on the Carbon being the surface layer and having the Kevlar as the base but as someone else said trying to sand or finish the Kevlar will make it fuzzy. When working with Kevlar you'll need a brand new pair of scissors and make sure you only use that pair for the Kevlar. I have countless scissors that have been "Kevlared". Use it for anything else and after that it doesn't cut the yellow stuff. Best advice is to make sure to trim the Kevlar at the mold edges with a box cutter when the resin is just past the green stage. You'll get a clean cut that requires no finishing.