Modified CVA Buttstock

[rharbaugh]

Many thanks to all the pioneers on here who inspired me to take a miter saw to my CVA buttstock. The original geometry of the comb and toe made shooting the thing with a scope pretty uncomfortable. Additional the grip and trigger reach left something to be desired. Hijacking a little bit of all the methods that others have posted with their DIY mods, and trying to emulate the Rokstok here is my progress so far.

Started with a simple trace on some grid paper so I could line up the barrels and triggers so I could see where I need to cut the original stock


Next step was to use an oscillating multi tool to cut off the cheek pad. The plastic stock more or less melted vs cut. Post cheek pad removal with some sanding. The holes are from where i previously had added a cheek riser and QD cup. White line along the toe is where I need to make my cut. White line along the grip is the through hole to attach the stock to the gun.

Miter saw cut. The cut ended up not being square to the stock, so the toe now has a little cant left to right. I'll fix that with puddy later.

Back on the grid paper for a visual. I initially thought of reusing the stock material, so that's why that's in the pic.
Decided to use a carbon fiber arrow shaft. I'm missing some pics of where I drilled holes and then JB welded the arrow shaft to the stock and the shafts together. Here's a mock up of where I wanted the shaft for the comb, also added a shaft that goes vertical out of the rear of the stock in front of the recoil pad. These two shafts are connected with JB weld at the top/rear of the stock.
After re-reading other DIY post and taking consideration of my skills and tools, I decided to use "Free Form Air", a two part epoxy dough. This has been a great material to use IMO because it's easy to mix and handle, forgiving on time set, easy to sand, and cures pretty hard. Here's my first application while it's still "wet".
After a little sanding.



Second application of Free Form Air and some sanding

 

[rharbaugh]

Third and final application, sanded down.


Ready to start my journey into DIY carbon fiber.


Thanks to @Gobber I called the folks at Soller Composites to get my carbon fiber, breather cloth, and peel ply. I went with 3k twill and plan on doing a minimum of two layers. I have a hunt coming up Dec 10 that i need to get this ready for, so we'll see how many layers I can get it, I'm not worried about aesthetics at all.

With this being my first rodeo with carbon fiber, I'm not going to get super invested with the proper vacuum pump and bags. My plan is to use my LEM MaxVac 500 and some 14" wide vac sealer bags. Might be tricky getting things lined up in the bag, but should be able to pull a vacuum down, seal it, and leave it to cure. I chatted with the folks at Soller and they thought this would be a good approach.


I could use some help from others on how I should go about attaching my recoil pad? Any input here @RepeatPete @hpmr @Ice-kub @ResearchinStuff on things that you did that worked well or other approaches you wish you did? Thanks in advance!

 

[rharbaugh]

Well i'm not going to go down as the Picasso of DIY carbon fiber, but i'm on the board. We'll see how things are in the morning.

 

[rharbaugh]

Failure has been a great teacher (as usual) for this project. I'm no expert, but i'm definitely getting better at making things not look like compete garbage. Maybe these are well known practices, but here are a few things that I started doing that I haven't read in other DIY carbon fiber threads.

I started making stencils out of paper prior to cutting my carbon fiber. With so many curves on this project, I was really struggling with cutting squares or rectangles and expecting things to lay and cure nicely. Making the stencil allowed me to dry fit things before carbon fiber started fraying and epoxy was getting everywhere. Here's a pic of a lay on the grip area after using a stencil cut out.

The stencils also helped me with my carbon fiber material management. Again, probably well known, but cutting into a large roll of carbon fiber weave without any "anti-fraying" steps in place created a headache, a lot of ruined material, and some ugly material. Using my stencil I could lay it on the weave dry and then use masking tape to section the appropriate amount of material that i needed for that piece. Cutting down the middle of the masking tape kept the weave from fraying, both the piece I was going to use and the remaining roll.

In the same vein of masking taping off pieces. Once I cut out the portion of weave that I needed for the next lay, I would lightly spray it with some 3M Super 77 spray adhesive, preventing further fraying when I would cut the outline of my stencil from the weave.

Rereading @mddat Modified my Tikka stock thread, I picked up on his electrical tape technique to compress the weave to the stock, which was hugely helpful for me around some of the more complex curves on my project. Thanks mddat! Here are some pictures of that, before and after.