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  #1  
Old 07-23-2019, 03:10 PM
Gobber
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Precision Plinker Stock



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Ok, new project time. Comments and questions are welcome. I’m doing most of this for the first or second time and am totally open to any tips or suggestions.

While knocking around the woods and range with a previous Coosa/carbon fiber stock for a few years, I thought of several aspects of a new version. The first version still fits well, but there was no easy way to alter the grip. But I have to say, the carbon fiber / Coosa board construction has held up very well- no separations, cracks or failures. For the next version, I definitely wanted less Coosa and more carbon fiber that would take advantage of hollow core areas to maintain strength and be lighter. New version will be a ‘chassis’ style design with interchangeable grip, butt and comb fixtures. Besides, it was time to scratch that itch to tinker with a new project.

Here is a shot of the previous version


So here are the materials to be used.


Another part of the project is to use common, fairly inexpensive tools. Since this is a one-off item, the method I employed was simple vacuum bagging of CF over various core materials – Coosa, foam and CF tubing. This allows for changes and repair of the original item without any complex retooling. The next level in CF fabrication involves molds, bladders and heat curing which is a bit more involved than needed for this project.


The way I looked at it - you can make something that is Quick, Functional, Cheap... Now pick any two. I went with Functional and Cheap. The advantage of this being a long term project is that I could work on a bit at a time. It works for me to chip away at it an hour here, a few hours there. That best fits my schedule and it works much better when trying new techniques. Much of this build was a ‘learn it as you do it’ process. I actually saved time in the long run by slowing down and considering various methods of fabrication.

Since I don’t have access to a milling machine, CAD set up or expensive stock making gear, this was going to be a low tech process. Additionally, when it comes to working carbon fiber on a tight budget, the remote control model making community have really got their act together. Take the need for a pump unit for vacuum bagging. Off the shelf, they run into the hundreds. But a fridge pump makes for a great low volume vacuum rig. Made mine with a few extra parts and it has been running fine for over five years.


Another thing that occurred to me is that carbon fiber can be thought of as a modern day equivalent of folded steel in feudal Japan. A bit of knowledge with the right materials and you can fabricate a quite effective tool with some very unique qualities. And you can make it in most any form you like. Cool thing is that the components are not as out-of-reach as you might think.

So for this build, I broke the stock down into separate components that can be made (and remade) to suit specific desires. The main ‘chassis’ is comprised of three sections – hexagonal barrel shroud, main body and rear assembly. Add to this a grip, comb & butt piece and you have yourself a pretty cool stock.

A couple of materials make this project come together, so to speak. Where the action screws and bedding compound are mounted, there needs to be a core material that is light, easily cut & sanded and readily bonds with epoxy. Wood will work, but I really like Coosa board since with a .22LR, recoil is not an issue. A great supplier is BoatOutfitters.com as they sell a 1/3 sheet. The hex tube for the shroud is readily available from Rock West Composites. I tried making my own off of an aluminum hex mandrel, but found it is not worth the trouble.

Cutting CF – really have to use diamond tools. Cheap Dremel sets are available on line. A really good round cut off wheel is the one from Dremel – lasts a long time, the holes get rid of the waste and the spring loaded clip gives it a bit of flex. Make sure you have good ventilation and use a fine filtered vacuum and mask. Stuff is not good to breath!

Chassis Rear Assembly – Here is a great place to save some coin. Find a hockey player and get a broken hockey stick from them. Most sticks are now either all carbon fiber or a CF/Fiberglass blend. Buddy of mine is a team captain and gave me a few. You have to heat up the shaft and scrape off the tacky coating, but they make a great core for the back section. I went with a simple square shape with an angled side for my support hand with shooting prone.

To hold the joints in place, I used sections of Coosa as inserts and inserted sections as ‘hard points’ to mount threaded sockets and sling swivel studs. Once epoxied in place, they are really solid. You do have to be aware of Ferris metal in direct contact with CF oxidizing due to galvanic action. Just make sure there is resin separating the two.


To line everything up, I took a section of ¾” plywood, some drywall screws and small sections of plastic pipe to make a jig board to hold everything flat, level and in place. This worked well to fine tune the corner cuts by pulling sand paper between the two tube sections. It also held everything in place to epoxy it all together.



I cut the angle to match my hand position so it fits comfortably in the prone position. Cool thing about making it from scratch is you can customize any little aspect you like.


More to follow…

Last edited by Gobber; 07-23-2019 at 04:02 PM.
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  #2  
Old 07-29-2019, 05:38 PM
SillyMike
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Interesting!
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  #3  
Old 07-30-2019, 04:32 PM
Gobber
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SM - Thanks for the interest. It has been in the 90's here so working with resin can be a bit of a race, but I will try to get a few more process pics.

Chassis Main Body –
The main body section is both simple and complex. Simple in that it consists of two blocks of Coosa board encased in carbon fiber. Complex in that there is a good bit of process to shape it for bedding, insertion of screw mounts and fitting to receiver. This main body really needs to be fitted to the receiver before mounting the forward hex tube and rear stock section to ensure everything lines up properly to the rifle’s action and trigger. In the past I’ve sandwiched it all together and cut out the needed areas from the one monolithic block. This time I’m trying something different by using a clam shell technique. In the hope of cutting down some of the workflow, the two sections of Coosa will be mounted to a jig board and have the initial stress bearing side layers CF layers applied. The Coosa sections is pegged to allow it to be shaped as a single unit and then split open when needed to cut the holes for the screw mounts and any other inletting. Not sure if this will speed or slow the process, but it’s worth a try. The space between the inletting grooves on the bottom of the receiver is right at 123mm. I mounted a block that size onto a backboard to act as a jig. Next covered the needed areas with releasing agent and applied one layer of CF. It’s easier to see the results in reverse order.

Here is demolding the sections. Thankfully, no mechanical locks. The pink film is the releasing agent doing its job.


Here it is after pulling off the vacuum bagging layers. The spacer is just a tad below the level of the Coosa sections so I built it up with duct tape. I figure if there is a bit of a dip, it will be easy to add a bit to level it out in the next few layers.


Here it is in the vacuum bag for curing overnight.


One layer of CF is really flimsy which is not surprising. Just wanted to do a single layer to make sure it came off easily. I’m thinking I will do two more layers with the middle layer applied at 45 degree offset. Hopefully that won’t create too much waste, but it will be interesting to see how much strength this will add. Cool part is that if you need more strength, just add another layer.

More to follow…
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Old 07-30-2019, 05:27 PM
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Is that a hockey stick in the first picture?
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  #5  
Old 07-31-2019, 10:21 AM
Gobber
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AZTarget –Good eye! That is a hockey stick in the ‘materials’ picture. A buddy of mine is a big hockey player who breaks about 3-4 sticks a year. He uses carbon fiber shafts that typically break at the blade and there’s no repairing them. So he gives me the shafts. Ever mindful of cost and loving to repurpose things, I use them for the core of the rear stock section.

Only issue is removing the tacky surface applied to modern hockey sticks. A bit of time with a heat gun and pallet blade and I get a nice section of CF tube. The exploded pic above shows a section of hockey stick cut to size.


I will do more of a write up on forming the rear section later once I get a few more pics of the process.

Took a few more pics of the layup process to show the order of the workflow a bit better. This is the cut of the second layer that will be applied at 45 degrees for added strength. It will be interesting to see how well it works.


You really have to tape the seams or it will shed strands all over the place. Makes it much easier to cut.


The roll on the table is two yards of 6K CF that goes for about $25/yard. Good thing is that it’s 50 inches tall. The tape is from Tamiya and works really well with resin. It’s just the right width to cut in half and after the resin saturates it for a while, the adhesive lets go so you can pull it out of the layup. Not a big deal for this one as the edges will get trimmed away, but for other times it is good to be able to remove it.


To prepare the mold board, I use plenty of releasing agent. Painted it on this morning so it should be nice and dry this evening for another layup.




I will try to get some shots of the layout for applying the next layers tonight. Once you get the process down, it goes fairly quickly.

Last edited by Gobber; 08-21-2019 at 04:50 PM.
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Old 08-02-2019, 02:14 PM
gpkon66
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Interesting write up. Thanks!
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Old 08-04-2019, 06:53 AM
Gobber
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GPKON66, thanks for the interest

So, made a bit more progress on the main body. Here is the prepped layup ready to be wetted out and bagged. CF is cut to size, mold has release agent dry (hence the glare), the peel ply (blue) and the batting (white) fabric is cut to size and the green vacuum bag with the blue and white end sealing rod ready to put the whole enchilada in.


It took three pumps of resin and had to move quickly to get it spread onto the fabric as it was pretty warm today. Sorry for no pics of the resin work, but it is pretty sloppy and didn't want to get it all over my camera. So here are the new layers thoroughly soaked and laid in place. Orientation of the weave of each layer is 90deg, 45deg, 90deg. Don’t know if this will really make a difference in the long run, but just wanted to give it a try. In reality, if the piece needs to be stiffer, just add another layer. Not really that worried about pattern orientation or a perfectly level finish. I can put a bit of filler (resin with micro-balloon thickener) and then flat sand it smooth. It’s the final layer of CF over the whole assembles stock body that gives the final finish. These are all interior structural pieces.


So here it is with the bag in place and the vacuum pulled. Once again, not terribly worried about small wrinkles in bagging, but it was a booger getting the whole ‘sandwich’ into the bag with the peel ply and absorbent batting nice and flat. Reason was a bit of residual resin on my hand after I pulled off the gloves. Note to self- wash hands with vinegar first and then soap, then go outside and spray a bit of silicone lube onto hands so they don’t stick.


Next morning, it’s set up enough to de-bag and pull off the mold. This bag has been used at least 6-7 times and is getting pretty worn out. You can see a bit of duct tape over a small hole from a previous layup. Hey, whatever works


Now the fun part! I always like pulling the peel ply. Big lesson learned, use a much larger section of blue peel ply than the white batting material. The peel ply peels off easily from everything- hence the name. The batting material doesn’t- it can become a laminated layer and a pain to remove. The pliers really help removal and act like the old spam cans with a key. Big thing here is to avoid the edges of the CF- it is flattened out and tapered down to a knife edge. One slip while pulling can give you a nasty cut.


Here is the piece pulled from the mold. It takes a bit of prying, but once it pops loose, it comes off pretty easy. The pink film of the release agent comes off in small sheets with the rest easily washing off with a bit of water. I like to pull the piece before full cure as it has a bit of flex.


Next is to simply trim away the excess. Here is where you want a vacuum running close to catch all the dust. I work with an overhead fan running and will mask up if needed. This is also why I like to work the piece before full cure as it is not so dusty when trimming off the excess.


Here is the trimmed up piece with the mold. A lot of the Coosa material will be sanded away for the final fitting, but I wanted enough material to be able to clamp it in place to be worked.


Ok- this is all pretty strait forward stuff- laminate two blocks with CF. The cool part comes next…
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Old 08-05-2019, 11:54 AM
Gobber
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Now for the good stuff. Time to begin inletting the interior sections for the fittings and action. It’s a pretty strait forward process to trace an outline of each component at a time starting with the action only. To get the depth of the cut, just measure the width of the item to inlet and divide by two. By working from the center-line of body section, it’s much easier to trace, measure and router out the needed voids.


I use the router attachment to a Dremel to cut out the needed pockets. Good thing is that the cuts don’t have to be all that precise because it will be cemented in place with resin thickened with micro balloon powder. This works well because it lightens the resin, but still remains really strong. It also theoretically disperses more of the recoil forces, but with a .22 that’s not much of a concern.


Next step is to put the rest of the components in place and route out the areas needed for them to fit. When cutting Coosa with the router attachment, it’s good to have a vacuum hose right there to catch the dust as there are fiberglass layers that get itchy pretty fast. I also glove up.


The channel for the barrel was sanded out using a 1” drum sander on a drill. Since it will be set using Marine-Tex, the cutouts do not need to be all that precise as they will be filled in.



The little brass screw mount escutcheons are fabricated from brass endcaps for ¼“ line. I really like these caps because the original head of the original Izhmash mounting screws fit perfectly into the pocket plus the caps have a center mark on the inside that make it easy to drill.
https://www.homedepot.com/p/Everbilt...1129/207176287



After drilling a pilot hole and working up the sizes, a 7/32” bit gives just the right size hole to use the screw to tap out the hole. All I want is to capture the screw so it doesn’t fall out. By running it up and down a bit with a driver, it becomes loose enough to hand turn it through. I like to turn down the endcap a bit on the belt sander to give a nice rough surface for the resin to grab onto. Not really that necessary but it only takes a few minutes.


Next I cut a small section of brass pipe from the hobby store to keep the finished hole nice and neat.


By using a C clamp, the two can be held in place for a quick silver solder.


Another quick turn on the belt sander and it’s shiny and clean.


Now that this half of the main body has been routed out, I will lay up the other half over night and do the same thing all over.

Last edited by Gobber; 08-07-2019 at 07:37 AM.
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Old 08-05-2019, 12:47 PM
hara-julu
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This is awesome! We have seen a number of carbon fiber stocks in biathlon, but only for the pro's. What do you think about an integrated mag holder?
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Old 08-05-2019, 04:16 PM
Gobber
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HJ – Glad you like the project. I have always liked the look and function of the pure biathlon stocks. The older biathlon stocks seemed to have big bellies about the mag wells, but the newer ones have really cool lines. For this project, I am going for a more skeletonized shape. Buddy of mine calls them ‘space gun stock’ which is a pretty good description

Here is a quick knock up of a carbon fiber magazine cassette for a 10rnd mag. It works well, but the next one will have a bit more of a positive engagement. Don’t want to be banging around in the woods and loose one of those 10rnd ‘unobtainium’ magazines.
It sets on the right side of the rifle opposite a hollow cheek rest formed off a bit of ¼ round molding. That’s the bit standing up behind it.


I also did one out of Kydex for a previous build that worked very well. I really like the Kydex as it is a softer material that the glass filled nylon type material the Izhmash mags are made from.


I am mentally working on a cheek rest that has an integrated mag cassette for a 10rnd mag. I realize that a square shaped cheek rest is probably going to be more comfortable than the rounded one I currently have, but that is down the road just a bit.

Last edited by Gobber; 08-21-2019 at 04:55 PM.
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Old 08-06-2019, 10:02 AM
Gobber
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As for the rear stock section, it consists of sections of CF hockey stick tubing with sections of Coosa in the corners.
Once the sections are cut, a length of 80grit sandpaper is double up and pulled through the corner cuts to neaten them up.



The corner braces are cut and sanded into shape.
A small handsaw or Dremel cutoff wheel works great and then a bit of shaping on a belt grinder. The white X’s are the fiberglass layer showing through.




Here is a shot of the sections prior to setting in resin.


To put it together, a slurry of epoxy resin with a bit of micro balloon thickener and a touch of black dye works well.
I wait about a half hour to allow the resin to begin to thicken so it doesn’t run too much.
Here is a shot of placing the forward brace.
The angle that is most comfortable for my weak hand support when shooting prone is about 66deg.


Once it’s all glued up, it’s place back on the jig board to keep everything flat and level.
I clamp it down tight so all the seams set nice and tight.
Don’t forget the wax paper for release!


Next morning pop off the clamps and it is one solid block.
There will be a bit of flash to sand off.


Once all the bits of flash are removed, the whole surface is given a good sanding so the final layer of CF will bond nicely.


Last step is to cut it off with a bit of extra length to be inlaid into the center section.


The fittings for the cheek rest and butt stock assemblies will be added later.
The surface of the threaded sockets will be left raised above the surface a bit so then the final CF layer is applied, it is easy to sand them down so the top of the fitting shows.
In order to set the threaded sockets for the cheek rest, two blocks are shaped to slide down the tube.
Once the holes are drilled, the resin is applied through the holes and the blocks are pushed into place with a pre-measured rod.
The next morning the inserts are solid and the holes can be drilled to set the threaded studs.
More on that later as I have to get the right sized studs.


And the really cool stuff is yet to come…

Last edited by Gobber; 08-21-2019 at 04:57 PM.
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Old 08-08-2019, 08:32 AM
Gobber
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Get a Grip Man!

Now I think this part is really cool! After a few tests, came up with a way to create a completely custom fitted, light weight and quite rigid grip.
To start with, I made a reusable blank mold for making foam blocks out of Smooth-On Foam-It Rigid 5.
The mold walls are from a section of coroplast which is the stuff plastic signs are made from. Great stuff BTW as it's basically corrugated cardboard made from plastic.


I use a section of polyvinyl pipe as a mounting post so the foam can be easily mounted in a vice for sanding and shaping.
The poly tube is also good because the foam will release from it with a good twist.
Prior to pouring in the foam, I cut a small CF plate to imbed into the top of the foam to act as a hard point so I can bolt up the plug to the chassis to make final fit adjustments.


After doing the math, it takes exactly 30ml each of the two part foam from Smooth-On.
After a liberal coating of release agent has dried, follow the mixing directions and don’t monkey around when pouring it into the mold.
When this stuff kicks off, it expands in less than a minute or faster if temp is above 85deg.
When sealing up the box, it is best to contain the foam with only small gaps for the excess to push out of.
This gives a higher density to the foam which holds its shape better during vacuum bagging.


Once the foam sets up, pop the block out.




The sides typically bulge a bit so a bit of flat sanding helps true it up a bit.
Low tech sanding block is a section of oak trim board, some 3M heavy duty double sided tape and strips of 40grit sanding belt. Cheap, effective and easily replaced.


A simple trace of the general shape of the grip makes it easy to cut and sand plug down to the rough outline.




Here is about 20 min of sanding with 40 grit strip and block.
The Smooth-On Rigid 5 foam has just the right density to sand easily but still be firm.


More to come on really fine tuning the fit.
But for now- it's starting to look like something resembling a rifle stock.
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Old 08-13-2019, 03:38 PM
Gobber
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Well, as the saying goes, "Two steps forward, one step back..."

After working with the two part mid-section, I realized a few things.


By doing a two block lay-up with a spacer in the center of each half, the surface will have a small crease. It shows up a bit in this photo, but is more pronounced when viewed at an angle.


In trying to flat-sand the surface, it takes off too much material. Trying to do slight buildup of the area to level it up is just too much trouble. Also, there are a few areas in the void area where the action goes where it needs some core support. Going back in and adding Coosa material after the fact would be too much trouble.


So it was back to the drawing board to make two new, one piece core sections. This was actually not that big of a deal as it is simply cutting out two sections of Coosa and the fact that this will make things easier further down the process for a couple of reasons. Turns out that routing out the Coosa is much easier than anticipated and I can take away just the right amount of material in the places needed. It will also be easier to better shape the exterior contours of the solid block of Coosa prior to applying the CF layers. Hopefully I got the shape right this time and will not have to add any spot CF reinforcement sections.

So I did a rough cut of the two halfs and set a few CF pins to hold them in place for shaping.


In re-tooling for this small process change, I am now able to cut and shape a two part plug much closer to the finished shape (hopefully) and cut down on waste.
This was smoothing out the arch just forward of the magazine well.
A few minutes with a drum sander and it makes a nice smooth contour.


Next was to round off the area.
Some 80 and then 120 grit sandpaper used like shining a shoe give a nice, even rounded contour.
That little divot in the middle of the arch was where a set pin was located.
I cut out a small bit of Coosa and simply super glued it in place then smooth it out. No biggie as it is buried under the CF shell.


Once the shaping was complete, a few taps with wedges pulls the half apart.


Once apart, I traced out the final outline onto a bit of sheet steel to make a template to aide in the initial rough cut of the initial core plug section.
The strait cuts were done with tin snips, but the arches had to be ground out with an abrasive wheel.
Once sections were cut, it was easy to snap them off.
After a few minutes of sanding, the template has smooth edges for tracing.


Next was to anchor the two halves to a board that was pre-treated with releasing agent.
Ran a few drywall screws in from beneath to hold the cores in place.


To aid in better fabric adhesion to horizontal corners, I added some buffer blocks to the layup to allow the vacuum bag to apply better pressure to the hard to reach areas.


Next morning, it was hardened up nicely.
After pulling the bag off and pulling off the peel ply, it looks good.
There were a few minor wrinkles, but since it is over a solid core, a bit of flat sanding will level it all out.


Cutting away the flashing.


Inside view with all the rough edges.


Rough edges sand off easy enough with some 40 grit, that is after changing out the 120 grit.


After a bit of flat sanding and touch up, nice and smooth where it counts.


Next will be routing out the interior for fitting in the receiver, action and mag well.
For that, I ordered a new router attachment for the Proxxon that should allow for much more exact cuts.
It will be interesting to see how it works out.

Last edited by Gobber; 08-13-2019 at 08:55 PM.
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Old 08-20-2019, 11:23 AM
Gobber
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The new Proxxon router attachment arrived and is a real improvement over the old dremel attachment.
As with some of the Proxxon attachments, it is best to do a quick disassemble, deburr and lubricate.
After that, it works very well. The spring loaded plunge with depth adjusting threaded guide is really nice and makes it much easier to set a more precise depth.
The larger flat area means you can reach out further on a flat plane to get a good, level cut.


Now, on to cutting.
Turns out that forming the halves of the main body out of one solid slab of Coosa makes things much easier in a few ways.
By pulling the CF over one continuous surface yields a much more uniform CF side finish that only needs a little bit of flat sanding to level off.
It is also very rigid with virtually no bend, so routing out areas is much easier.

Receiver Channel - Cutting out the receiver bedding void was done by first marking the depth of the channel on the inside face.
Note: The black vertical line is my main reference point that is set to the back of the receiver. This is what I take most all of the measurements from.


The top cut is made by marking the width of the channel from the centerline out to the edge of body’s top surface.
I try to measure everything from the centerline out to avoid minor measurement errors.
I then cut out the top layer of CF using a make-shift rip guide.
There is a bit of room for error as it will be filled by the bedding compound and sanded flat.
Then the final finish will be done into the last layer of CF.


Removing the arc of the channel was done with a drum sander that gives the relief needed for the receiver to fit in.
This initial radius was evened out later when the halves were put back together.


Set Screw Cut – I initially cut the channels for the set screws escutcheon fittings using a round burr to give a more radiused cut. However it became evident that it would have been much better to simply drill this area out with the halves together.


Cutting them out as channels was a waste of time because in doing it ‘free hand’, there was no way to be precise enough so when the halves are put back together, everything lines back up.
Not a big issue as it will all be filled in when the fittings are epoxied in, but still a bit of a pain.


In cutting out the main void for the action you have to make sure the flat bottom of the router is kept level with support from the face of the slab.
One way to do this is to cut out channels while leaving a bit to support the flat of the router attachment.
Pretty fun actually, so long as the vac is close at hand, otherwise it gets a bit gritty.
Eventually I left one ridge in the center of the void to be cut away last.
Halfway through it looks like big termites at work.


Lesson Learned - Without the ability to lock the piece onto an x/y milling table for really precise cuts, I find that leaving that bit of extra material on each internal edge makes it easy to touch up with a drum sander when the halves are together. It takes a bit of fine tuning the voids to make sure the action can be lifted out of the stock.


Since my plan is to bed both the receiver and the trigger guard with Marine Tex, the cutouts don’t have to be really close tolerance.
Of course the closer tolerance, the less bedding compound needed which saves a bit of weight.

Turns out that the fitting cutouts are all in pretty close proximity, so there is not much wasted space within the core of the main body.
That efficiency of space is good for keeping weight down, but it gets a bit tight in there for cutouts.
Since the internal threaded fittings will be set with micro-balloon filled resin, it should keep a bit of the weight down without losing bonding strength.


All this prep is where the real work is.
Also figuring out what the most efficient method for each step eats up a good amount of time.
Taking notes on measurements and making a pattern for the initial Coosa cutout will save time in the future.


Last cut out was for the stock tube section inset.
Initially setting the LOP to just under 13” to allow adequate space for the shoulder fitting.
Since it is adjustable, it is better to be a bit short than too long since it’s easy to add length with spacers.
Another added benefit is that it will allow for a much shorter LOP for a smaller person.


I set the depth for each cut out at half the width of the stock tubing and after tracing the outline of the tube, cut the void out.

Here is a little touch I thought I would try.
Since the escutcheon opening is right where the main arch of the mag well, I cut a long section of brass tubing to act as a liner.
Once it is set in place, I will cut it off just a bit proud of the surface.
That way when the final layer of CF is applied, the interior of the tube will be leveled with clay to keep the excess out.
Once cured, it can be filed away for a nice flush fit – at least that’s the plan.
It can then be polished as a nice accent or darkened to a patina.


The parts are actually starting to look like something resembling a rifle stock.




Now I’m going to have to think a bit about the best sequence to set everything together.
Also need to do a bit more prep work on the stock tubing section prior to setting it in place.
Sorry if the explanations got a bit confusing. Not being a machinist, I don’t know all the right terminology and am just trying to be descriptive.

Last edited by Gobber; 08-21-2019 at 05:17 PM.
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Old 08-29-2019, 02:16 PM
Gobber
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Back at it…

Made some progress in a few areas over the last few days.

Stock – Settled on an order to proceed. Set the halves together, bed the action, then set the escutcheon fittings.
Here is the layup of the main body halves with thickened resin plus a bit of black dye.



The micro-balloon filler does a great job of thickening the resin so it stays in place. BTW- resin dye is the blackest stuff I have ever encountered.


Here it is clamped up to cure. The taped on wooden spacers on the stock tube are to make sure it stays true and level with it is clamped into place for curing.


Next morning it was one, solid unit that was ready for bedding the receiver. Since recoil is not an issue with a .22, going with Marine Tex dark gray.
I like that it cures nice and solid, but doesn’t abrade the receiver surface over time. Plus, it’s what I had on hand.
This is the part that always makes me nervous, but after reading some recommendations on how to mix and apply the bedding compound, it went much smoother.
Taped off the receiver and put two coats of releasing agent – just to make sure no mechanical locks.


Did the same to the bedding channel of the stock. So as to not use too much modelling clay in the trigger / mag well void, I took a bit of scrap wood and sanded it down as a plug that fit the void. That way, only had to lay down about a quarter inch of clay to keep the bedding compound in place. This was before I taped the rest of the stock body up.


Here is the receiver with final preps. To line up the action screws, I like to use dowels as guides that can then be pushed through a thin layer of modelling clay in the action screw holes.


Now for the bedding compound. The two tips that worked well were-
1. Mix the compound on a long, flat surface that has an area marked off that is roughly the size of the void to fill. This makes it easier to gage how much material to use.
2. In mixing in the hardener, don’t swirl in circles but fold the compound over to keep bubbles to a minimum. This also help keep the mix cool for longer work time.


Lay the material into the barrel channel first using a buttering motion that rolls the compound into place and keeps air voids to a minimum. Butter the compound onto the receiver next using the same technique.
Here is the sandwich ready to press together. It’s also the part that makes me sweat the most.


Seated the pieces together and pushed the excess out of every crack, then tacked it into place immediately so it wouldn’t move and suck air back into any voids.


Once in place, made sure the barreled receiver is bedded strait and level.


Well, the tip about using an outline of the area to estimate the compound to use worked very well. There was a nice bead of about 1/8th inch excess that squeezed out and was cleaned up with a mixing stick.


Next morning, the two popped apart with a nice snap like breaking a candy cane.
Whew- what a relief!


Here is the barrel channel with most of the clay removed. The compound filled the area below the action and will be trimmed and sanded to fit later.


Talk about a tight fit, the Marine Tex picked up the image of the serial number from under the receiver.


Putting the action back in the stock was really tight so there will be some sanding and relieving to make a good releasable fit.
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