Release time:2020-11-03

Carbon fiber is frequently supplied in the form of a continuous tow wound onto a reel. The tow is a bundle of thousands of continuous individual carbon filaments held together and protected by an organic coating, or size.The tow can be conveniently unwound from the reel for use. Each carbon filament in the tow is a continuous cylinder with a diameter of 5–10 micrometers and consists almost exclusively of carbon.Carbon Fiber Tow is the thread used to weave carbon fiber fabrics. The number of filaments per tow determines what -K the weave is (i.e. 3k means there are 3,000 filaments per tow). There are several  different appearances.The most common ones are UD,3k and 12k.UD/3k/12k specify the carbon weave pattern.

UD carbon(Uni-Directional) has fibers that run the same way rather than being woven together. In addition to the regular UD parallel patterns, we also offer custom patterns such as the "X " pattern,"Butterfly " pattern.Custom weave requires a complicated carbon layup,we will charge an extra cost $15-25 according to the pattern requested.

EIE carbon fiber material weave ud and braided ud pattern

3K means there are 3,000 filaments per "tow". EIE can offer several variations of 3K weave,including 3K,3K Twill (horizontal),3K Twill(vertical) etc.You can select 3K twill options in our shopping configurations.If you need specific horizontal or vertical pattern, please leave a message on the nots or contact us at

EIE carbon fiber material weave 3K and 3K twill

12K means there are 12,000 filaments per "tow ".EIE can offer several variations of 12K weave,including 12K,12K Twill (horizontal),12K Twill(vertical) etc.You can select 12K twill options in our shopping configurations.If you need specific horizontal or vertical pattern, please leave a message on the nots or contact us at


Painted finish rim,we generally have matte,glossy and satin these three painted finishes.

For the matte finish, the bicycle rim surface scratches(micro marring) may be not easy to see and it will help to hide imperfections in carbon layers. 

For the glossy finish, scratches can be buffed out. One of the virtues is that glossy finish will provide a "clear " barrier between the environment and your rim. Same riders prefer this kind of cool clear coating, because it looks very shiny and the effect is much like metallic, pearl, flip flop, etc. But the dirt and the scratches can be more visible.

For the satin finish ,its sheen between matte and glossy.This finish is closest to the rim without the paint treatment.The carbon is more visible than matte finish.

eie carbon fiber finish ud 3k 12k with matte and glossy finish

Paintless Finish(In-Mold-Decoration)

Our mountain bike rim 18.5mm shallow profile is available for Paintless finish which we called out "In-Mold-Decoration" series.It is only UD weave available.This tech brings more eco-friendly production line,and more better,light,stiifer rim performance.

How to use a proper ratio of 3K & UD to manufacture the lightest and strongest rims?

In addition to the apperance,we used only the 3K and UD for layup design . The UD carbon fiber grade and orientation will affect the strength of carbon rim(eg. 0 degree, 45 degree, 90 degree). The layup method is a crucial factor for every company. UD weave(in certain direction) creates a very strong structure.  But, if you drill a large hole in the middle of the rim, it has compromised the strength of the entire structure because you've cut/drilled almost all the fibers.

For 3K, it's OK to drill a hole in the middle which would not weaken the rim structure as much because your cut would have only severed a small portion of the total fibers and the drilled area is able to get support from it's neighboring (non-cut) carbon fibers. 3k weave is better because it is not as brittle as the UD.The weaving of 3K carbon fibers is similar to a spider's web. .To balance the ratio of carbon fiber and resin we often add a 3K layer inside of the rim channel to filter redundant resin. The small gaps inside the 3K layer also reduce the probability of defects on the rim surface. 3K weave also protects the spoke hole from tear-out during the drilling process. It displaces some of the pressure because it is not as hard as UD.

It is worth mentioning that the UD fiber has maximum strength when running in the same direction. Torsional stiffness and impact resistance are increased as angles are oriented in each layer.So we used 85 percentage of UD carbon fiber to create rim layup.

Why do we generally recommend UD weave rather than 3K or 12K?

Weave patterns have overlapping fibers, which is why woven fibers are usually heavier than UD.Even though the weight differences between the three are slight - about 10 grams.But if you prefer a lighter rim weight ,we suggest UD weave which can have a greater probobility to help you select a lighter rims.

Of course ,if you do not mind we may produce a heavier rim weight,12K or 3K weave has more noticeable carbon fiber.