2.0 It Has Begun - The First Carbon Fiber Layup
After about 10 hours of measuring, more measuring, cutting, itching, and laying up this build has finally begun! The first piece that I am laying up first is a 48"x34" flat panel that will be used for the chassis structure. Four pieces of the case's chassis will be water jet out of this large piece.The Process:
The first thing I started with was unpacking the roll of carbon fiber cloth. One of the biggest and most annoying tasks with large carbon fiber lay ups is aligning the weave. When CF cloth is rolled up from the distributor, it's rolled loosely to preserve the quality of the weave. While rolling it loosely prevents the weave from distorting, it does allow the weave to shift during shipping.
The tape at the end of the cloth was a straight cut from the factory, but the loose rolling and shipping has caused the cloth to distort a little bit. A lot of time is spent straightening out the cloth to make sure the weave is straight as possible.
Several important tools, a straight edge (I'm using a 2meter long piece of aluminum), masking tape, and a marker. Here I am using blue tape for straightening out the weave as discussed in the last picture. Avoid using blue tape on your pieces to be laid up. The blue tape has much more adhesive than white masking taping, so it is good for straightening out the weave while keeping the fibers in tact.
One of the most important tools is a good pair of scissors. I like these spring-loaded Fiskars scissors for cutting the cloth.
When I roll out the CF and measure out the amount I need, I like to tape the cloth to the table and mark the measurement.
Now that I've unrolled the amount of cloth I need, I have taped using 1" wide white masking tape all the way across the width of the cloth. I then used my straight edge to draw a line straight across the cloth to cut along. I will repeat this process four times, since I need four layers of cloth for my lay up.
Plenty of Monster to keep me going through the early hours of the morning.
Avoid folding the cloth, especially for larger lay ups like this. Folding distorts the weave that we worked so hard to straighten out earlier. Instead, I roll the carbon fiber back up onto cardboard tubes. Unrolling the cloth during the lay up is a lot easier than unfolding cloth. The two rolls each have two layers of cloth. For me, there are two types of cloth, Grade A and Grade B. Grade A cloth has a perfect weave with no pulls, flaws, or distortions. Grade B is structurally fine, but not as pretty. Grade A is used for the outer layers that will be visible, and Grade B for the inner layers.
It is very important to use a quality mold release. I like to use parafin wax. You can also see I am using a very large piece of 1/2" thick glass to lay up the CF on. The glass will is flat, and smooth and will leave a nice quality finish on the carbon fiber.
To help achieve strength and thickness I am using 1/16" balsa wood as the core for the lay up.
The Lay Up
I wish I was able to get better pics of the lay up process, but my friend that was supposed to help take pics bailed on me. So I was working against the clock trying to get the carbon wetted out and take pictures.
I am using US Composites 3:1 Epoxy Resin for wetting out the carbon.
First piece of cloth was laid onto the piece of glass and then wet out with the resin using a rubber squeegee/spreader.
After two layers of carbon fiber cloth, I laid the balsa core onto the wet carbon fiber cloth. The resin had enough tack to hold the balsa core in place while the other two layers of cloth were laid up and wetted out.
After 4 plies of carbon fiber and the balsa core, I laid a large piece of glass over the layup to help compress the panel and leave a decent finish. Instead of vacuum bagging, the weight of the glass will be more than sufficient for this panel.
Once again, quality scissor are very important. I use a separate pair of scissors for trimming the layup once the resin has begun to harden.
Lots of scraps. One of the things that sucks with huge layups is that you have a lot of scrap. I always cut my cloth larger than the piece needs to be just so I have room to work with and dont have to line up the plies perfectly.
That's all for now. Thanks for looking!
Originally Posted by yoi
this should be educational
, dont u have a design of the case? , are you going to do moulds? or just frame with CF panels?
I have a design for the case that I'll post later. I'll be making molds and panels. It will be a very long process!Edited by motorsportcfd - 12/31/11 at 1:40pm